tor-browser

make_intl_data.py (134274B)

---

#!/usr/bin/env python
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

"""Usage:
make_intl_data.py langtags [cldr_common.zip]
make_intl_data.py tzdata
make_intl_data.py currency
make_intl_data.py units
make_intl_data.py numbering


Target "langtags":
This script extracts information about 1) mappings between deprecated and
current Unicode BCP 47 locale identifiers, and 2) deprecated and current
BCP 47 Unicode extension value from CLDR, and converts it to C++ mapping
code in intl/components/LocaleGenerated.cpp. The code is used in
intl/components/Locale.cpp.


Target "tzdata":
This script computes which time zone informations are not up-to-date in ICU
and provides the necessary mappings to workaround this problem.
https://ssl.icu-project.org/trac/ticket/12044


Target "currency":
Generates the mapping from currency codes to decimal digits used for them.


Target "units":
Generate source and test files using the list of so-called "sanctioned unit
identifiers" and verifies that the ICU data filter includes these units.


Target "numbering":
Generate source and test files using the list of numbering systems with
simple digit mappings and verifies that it's in sync with ICU/CLDR.
"""

import io
import json
import os
import re
import tarfile
import tempfile
from contextlib import closing
from functools import partial, total_ordering
from itertools import chain, filterfalse, groupby, tee, zip_longest
from operator import attrgetter, itemgetter
from urllib.parse import urlsplit
from urllib.request import Request as UrlRequest
from urllib.request import urlopen
from zipfile import ZipFile

import yaml


# From https://docs.python.org/3/library/itertools.html
def grouper(iterable, n, fillvalue=None):
   "Collect data into fixed-length chunks or blocks"
   # grouper('ABCDEFG', 3, 'x') --> ABC DEF Gxx"
   args = [iter(iterable)] * n
   return zip_longest(*args, fillvalue=fillvalue)


def writeMappingHeader(println, description, source, url):
   if type(description) is not list:
       description = [description]
   for desc in description:
       println(f"// {desc}")
   println(f"// Derived from {source}.")
   println(f"// {url}")


def writeMappingsVar(println, mapping, name, description, source, url):
   """Writes a variable definition with a mapping table.

   Writes the contents of dictionary |mapping| through the |println|
   function with the given variable name and a comment with description,
   fileDate, and URL.
   """
   println("")
   writeMappingHeader(println, description, source, url)
   println(f"var {name} = {{")
   for key, value in sorted(mapping.items(), key=itemgetter(0)):
       println(f'    "{key}": "{value}",')
   println("};")


def writeMappingsBinarySearch(
   println,
   fn_name,
   type_name,
   name,
   validate_fn,
   validate_case_fn,
   mappings,
   tag_maxlength,
   description,
   source,
   url,
):
   """Emit code to perform a binary search on language tag subtags.

   Uses the contents of |mapping|, which can either be a dictionary or set,
   to emit a mapping function to find subtag replacements.
   """
   println("")
   writeMappingHeader(println, description, source, url)
   println(
       f"""
bool mozilla::intl::Locale::{fn_name}({type_name} {name}) {{
 MOZ_ASSERT({validate_fn}({name}.Span()));
 MOZ_ASSERT({validate_case_fn}({name}.Span()));
""".strip()
   )
   writeMappingsBinarySearchBody(println, name, name, mappings, tag_maxlength)

   println(
       """
}""".lstrip("\n")
   )


def writeMappingsBinarySearchBody(
   println, source_name, target_name, mappings, tag_maxlength
):
   def write_array(subtags, name, length, fixed):
       if fixed:
           println(f"    static const char {name}[{len(subtags)}][{length + 1}] = {{")
       else:
           println(f"    static const char* {name}[{len(subtags)}] = {{")

       # Group in pairs of ten to not exceed the 80 line column limit.
       for entries in grouper(subtags, 10):
           entries = (
               f'"{tag}"'.rjust(length + 2) for tag in entries if tag is not None
           )
           println("      {},".format(", ".join(entries)))

       println("    };")

   trailing_return = True

   # Sort the subtags by length. That enables using an optimized comparator
   # for the binary search, which only performs a single |memcmp| for multiple
   # of two subtag lengths.
   mappings_keys = mappings.keys() if type(mappings) is dict else mappings
   for length, subtags in groupby(sorted(mappings_keys, key=len), len):
       # Omit the length check if the current length is the maximum length.
       if length != tag_maxlength:
           println(
               f"""
 if ({source_name}.Length() == {length}) {{
""".rstrip("\n")
           )
       else:
           trailing_return = False
           println(
               """
 {
""".rstrip("\n")
           )

       # The subtags need to be sorted for binary search to work.
       subtags = sorted(subtags)

       def equals(subtag):
           return f"""{source_name}.EqualTo("{subtag}")"""

       # Don't emit a binary search for short lists.
       if len(subtags) == 1:
           if type(mappings) is dict:
               println(
                   f"""
   if ({equals(subtags[0])}) {{
     {target_name}.Set(mozilla::MakeStringSpan("{mappings[subtags[0]]}"));
     return true;
   }}
   return false;
""".strip("\n")
               )
           else:
               println(
                   f"""
   return {equals(subtags[0])};
""".strip("\n")
               )
       elif len(subtags) <= 4:
           if type(mappings) is dict:
               for subtag in subtags:
                   println(
                       f"""
   if ({equals(subtag)}) {{
     {target_name}.Set("{mappings[subtag]}");
     return true;
   }}
""".strip("\n")
                   )

               println(
                   """
   return false;
""".strip("\n")
               )
           else:
               cond = (equals(subtag) for subtag in subtags)
               cond = (" ||\n" + " " * (4 + len("return "))).join(cond)
               println(
                   f"""
   return {cond};
""".strip("\n")
               )
       else:
           write_array(subtags, source_name + "s", length, True)

           if type(mappings) is dict:
               write_array([mappings[k] for k in subtags], "aliases", length, False)

               println(
                   f"""
   if (const char* replacement = SearchReplacement({source_name}s, aliases, {source_name})) {{
     {target_name}.Set(mozilla::MakeStringSpan(replacement));
     return true;
   }}
   return false;
""".rstrip()
               )
           else:
               println(
                   f"""
   return HasReplacement({source_name}s, {source_name});
""".rstrip()
               )

       println(
           """
 }
""".strip("\n")
       )

   if trailing_return:
       println(
           """
 return false;"""
       )


def writeComplexLanguageTagMappings(
   println, complex_language_mappings, description, source, url
):
   println("")
   writeMappingHeader(println, description, source, url)
   println(
       """
void mozilla::intl::Locale::PerformComplexLanguageMappings() {
 MOZ_ASSERT(IsStructurallyValidLanguageTag(Language().Span()));
 MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));
""".lstrip()
   )

   # Merge duplicate language entries.
   language_aliases = {}
   for deprecated_language, (language, script, region) in sorted(
       complex_language_mappings.items(), key=itemgetter(0)
   ):
       key = (language, script, region)
       if key not in language_aliases:
           language_aliases[key] = []
       else:
           language_aliases[key].append(deprecated_language)

   first_language = True
   for deprecated_language, (language, script, region) in sorted(
       complex_language_mappings.items(), key=itemgetter(0)
   ):
       key = (language, script, region)
       if deprecated_language in language_aliases[key]:
           continue

       if_kind = "if" if first_language else "else if"
       first_language = False

       cond = (
           f'Language().EqualTo("{lang}")'
           for lang in [deprecated_language] + language_aliases[key]
       )
       cond = (" ||\n" + " " * (2 + len(if_kind) + 2)).join(cond)

       println(
           f"""
 {if_kind} ({cond}) {{""".strip("\n")
       )

       println(
           f"""
   SetLanguage("{language}");""".strip("\n")
       )

       if script is not None:
           println(
               f"""
   if (Script().Missing()) {{
     SetScript("{script}");
   }}""".strip("\n")
           )
       if region is not None:
           println(
               f"""
   if (Region().Missing()) {{
     SetRegion("{region}");
   }}""".strip("\n")
           )
       println(
           """
 }""".strip("\n")
       )

   println(
       """
}
""".strip("\n")
   )


def writeComplexRegionTagMappings(
   println, complex_region_mappings, description, source, url
):
   println("")
   writeMappingHeader(println, description, source, url)
   println(
       """
void mozilla::intl::Locale::PerformComplexRegionMappings() {
 MOZ_ASSERT(IsStructurallyValidLanguageTag(Language().Span()));
 MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));
 MOZ_ASSERT(IsStructurallyValidRegionTag(Region().Span()));
 MOZ_ASSERT(IsCanonicallyCasedRegionTag(Region().Span()));
""".lstrip()
   )

   # |non_default_replacements| is a list and hence not hashable. Convert it
   # to a string to get a proper hashable value.
   def hash_key(default, non_default_replacements):
       return (default, str(sorted(str(v) for v in non_default_replacements)))

   # Merge duplicate region entries.
   region_aliases = {}
   for deprecated_region, (default, non_default_replacements) in sorted(
       complex_region_mappings.items(), key=itemgetter(0)
   ):
       key = hash_key(default, non_default_replacements)
       if key not in region_aliases:
           region_aliases[key] = []
       else:
           region_aliases[key].append(deprecated_region)

   first_region = True
   for deprecated_region, (default, non_default_replacements) in sorted(
       complex_region_mappings.items(), key=itemgetter(0)
   ):
       key = hash_key(default, non_default_replacements)
       if deprecated_region in region_aliases[key]:
           continue

       if_kind = "if" if first_region else "else if"
       first_region = False

       cond = (
           f'Region().EqualTo("{region}")'
           for region in [deprecated_region] + region_aliases[key]
       )
       cond = (" ||\n" + " " * (2 + len(if_kind) + 2)).join(cond)

       println(
           f"""
 {if_kind} ({cond}) {{""".strip("\n")
       )

       replacement_regions = sorted({
           region for (_, _, region) in non_default_replacements
       })

       first_case = True
       for replacement_region in replacement_regions:
           replacement_language_script = sorted(
               (language, script)
               for (language, script, region) in (non_default_replacements)
               if region == replacement_region
           )

           if_kind = "if" if first_case else "else if"
           first_case = False

           def compare_tags(language, script):
               if script is None:
                   return f'Language().EqualTo("{language}")'
               return f'(Language().EqualTo("{language}") && Script().EqualTo("{script}"))'

           cond = (
               compare_tags(language, script)
               for (language, script) in replacement_language_script
           )
           cond = (" ||\n" + " " * (4 + len(if_kind) + 2)).join(cond)

           println(
               f"""
   {if_kind} ({cond}) {{
     SetRegion("{replacement_region}");
   }}""".rstrip().strip("\n")
           )

       println(
           f"""
   else {{
     SetRegion("{default}");
   }}
 }}""".rstrip().strip("\n")
       )

   println(
       """
}
""".strip("\n")
   )


def writeVariantTagMappings(println, variant_mappings, description, source, url):
   """Writes a function definition that maps variant subtags."""
   println(
       """
static auto ToSpan(const mozilla::Span<const char>& aSpan) {
 return aSpan;
}

template <size_t N>
static auto ToSpan(const mozilla::intl::LanguageTagSubtag<N>& aSubtag) {
 return aSubtag.Span();
}

template <typename T, typename U = T>
static bool IsLessThan(const T& a, const U& b) {
 return ToSpan(a) < ToSpan(b);
}
"""
   )
   writeMappingHeader(println, description, source, url)
   println(
       """
bool mozilla::intl::Locale::PerformVariantMappings() {
 // The variant subtags need to be sorted for binary search.
 MOZ_ASSERT(std::is_sorted(mVariants.begin(), mVariants.end(),
                           IsLessThan<decltype(mVariants)::ElementType>));

 auto removeVariantAt = [&](size_t index) {
   mVariants.erase(mVariants.begin() + index);
 };

 auto insertVariantSortedIfNotPresent = [&](mozilla::Span<const char> variant) {
   auto* p = std::lower_bound(
       mVariants.begin(), mVariants.end(), variant,
       IsLessThan<decltype(mVariants)::ElementType, decltype(variant)>);

   // Don't insert the replacement when already present.
   if (p != mVariants.end() && p->Span() == variant) {
     return true;
   }

   // Insert the preferred variant in sort order.
   auto preferred = mozilla::intl::VariantSubtag{variant};
   return !!mVariants.insert(p, preferred);
 };

 for (size_t i = 0; i < mVariants.length();) {
   const auto& variant = mVariants[i];
   MOZ_ASSERT(IsCanonicallyCasedVariantTag(variant.Span()));
""".lstrip()
   )

   (no_alias, with_alias) = partition(
       variant_mappings.items(), lambda item: item[1] is None
   )

   no_replacements = " ||\n        ".join(
       f"""variant.Span() == mozilla::MakeStringSpan("{deprecated_variant}")"""
       for (deprecated_variant, _) in sorted(no_alias, key=itemgetter(0))
   )

   println(
       f"""
   if ({no_replacements}) {{
     removeVariantAt(i);
   }}
""".strip("\n")
   )

   for deprecated_variant, (type, replacement) in sorted(
       with_alias, key=itemgetter(0)
   ):
       println(
           f"""
   else if (variant.Span() == mozilla::MakeStringSpan("{deprecated_variant}")) {{
     removeVariantAt(i);
""".strip("\n")
       )

       if type == "language":
           println(
               f"""
     SetLanguage("{replacement}");
""".strip("\n")
           )
       elif type == "region":
           println(
               f"""
     SetRegion("{replacement}");
""".strip("\n")
           )
       else:
           assert type == "variant"
           println(
               f"""
     if (!insertVariantSortedIfNotPresent(mozilla::MakeStringSpan("{replacement}"))) {{
       return false;
     }}
""".strip("\n")
           )

       println(
           """
   }
""".strip("\n")
       )

   println(
       """
   else {
     i++;
   }
 }
 return true;
}
""".strip("\n")
   )


def writeLegacyMappingsFunction(println, legacy_mappings, description, source, url):
   """Writes a function definition that maps legacy language tags."""
   println("")
   writeMappingHeader(println, description, source, url)
   println(
       """\
bool mozilla::intl::Locale::UpdateLegacyMappings() {
 // We're mapping legacy tags to non-legacy form here.
 // Other tags remain unchanged.
 //
 // Legacy tags are either sign language tags ("sgn") or have one or multiple
 // variant subtags. Therefore we can quickly exclude most tags by checking
 // these two subtags.

 MOZ_ASSERT(IsCanonicallyCasedLanguageTag(Language().Span()));

 if (!Language().EqualTo("sgn") && mVariants.length() == 0) {
   return true;
 }

#ifdef DEBUG
 for (const auto& variant : Variants()) {
   MOZ_ASSERT(IsStructurallyValidVariantTag(variant));
   MOZ_ASSERT(IsCanonicallyCasedVariantTag(variant));
 }
#endif

 // The variant subtags need to be sorted for binary search.
 MOZ_ASSERT(std::is_sorted(mVariants.begin(), mVariants.end(),
                           IsLessThan<decltype(mVariants)::ElementType>));

 auto findVariant = [this](mozilla::Span<const char> variant) {
   auto* p = std::lower_bound(mVariants.begin(), mVariants.end(), variant,
                              IsLessThan<decltype(mVariants)::ElementType,
                                         decltype(variant)>);

   if (p != mVariants.end() && p->Span() == variant) {
     return p;
   }
   return static_cast<decltype(p)>(nullptr);
 };

 auto insertVariantSortedIfNotPresent = [&](mozilla::Span<const char> variant) {
   auto* p = std::lower_bound(mVariants.begin(), mVariants.end(), variant,
                              IsLessThan<decltype(mVariants)::ElementType,
                                         decltype(variant)>);

   // Don't insert the replacement when already present.
   if (p != mVariants.end() && p->Span() == variant) {
     return true;
   }

   // Insert the preferred variant in sort order.
   auto preferred = mozilla::intl::VariantSubtag{variant};
   return !!mVariants.insert(p, preferred);
 };

 auto removeVariant = [&](auto* p) {
   size_t index = std::distance(mVariants.begin(), p);
   mVariants.erase(mVariants.begin() + index);
 };

 auto removeVariants = [&](auto* p, auto* q) {
   size_t pIndex = std::distance(mVariants.begin(), p);
   size_t qIndex = std::distance(mVariants.begin(), q);
   MOZ_ASSERT(pIndex < qIndex, "variant subtags are sorted");

   mVariants.erase(mVariants.begin() + qIndex);
   mVariants.erase(mVariants.begin() + pIndex);
 };"""
   )

   # Helper class for pattern matching.
   class AnyClass:
       def __eq__(self, obj):
           return obj is not None

   Any = AnyClass()

   # Group the mappings by language.
   legacy_mappings_by_language = {}
   for type, replacement in legacy_mappings.items():
       (language, _, _, _) = type
       legacy_mappings_by_language.setdefault(language, {})[type] = replacement

   # Handle the empty language case first.
   if None in legacy_mappings_by_language:
       # Get the mappings and remove them from the dict.
       mappings = legacy_mappings_by_language.pop(None)

       # This case only applies for the "hepburn-heploc" -> "alalc97"
       # mapping, so just inline it here.
       from_tag = (None, None, None, "hepburn-heploc")
       to_tag = (None, None, None, "alalc97")

       assert len(mappings) == 1
       assert mappings[from_tag] == to_tag

       println(
           """
 if (mVariants.length() >= 2) {
   if (auto* hepburn = findVariant(mozilla::MakeStringSpan("hepburn"))) {
     if (auto* heploc = findVariant(mozilla::MakeStringSpan("heploc"))) {
       removeVariants(hepburn, heploc);

       if (!insertVariantSortedIfNotPresent(mozilla::MakeStringSpan("alalc97"))) {
         return false;
       }
     }
   }
 }
"""
       )

   # Handle sign languages next.
   if "sgn" in legacy_mappings_by_language:
       mappings = legacy_mappings_by_language.pop("sgn")

       # Legacy sign language mappings have the form "sgn-XX" where "XX" is
       # some region code.
       assert all(type == ("sgn", None, Any, None) for type in mappings.keys())

       # Legacy sign languages are mapped to a single language subtag.
       assert all(
           replacement == (Any, None, None, None) for replacement in mappings.values()
       )

       println(
           """
 if (Language().EqualTo("sgn")) {
   if (Region().Present() && SignLanguageMapping(mLanguage, Region())) {
     mRegion.Set(mozilla::MakeStringSpan(""));
   }
 }
""".rstrip().lstrip("\n")
       )

   # Finally handle all remaining cases.

   # The remaining mappings have neither script nor region subtags in the source locale.
   assert all(
       type == (Any, None, None, Any)
       for mappings in legacy_mappings_by_language.values()
       for type in mappings.keys()
   )

   # And they have neither script nor region nor variant subtags in the target locale.
   assert all(
       replacement == (Any, None, None, None)
       for mappings in legacy_mappings_by_language.values()
       for replacement in mappings.values()
   )

   # Compact the mappings table by removing empty fields.
   legacy_mappings_by_language = {
       lang: {
           variants: r_language
           for ((_, _, _, variants), (r_language, _, _, _)) in mappings.items()
       }
       for (lang, mappings) in legacy_mappings_by_language.items()
   }

   # Try to combine the remaining cases.
   legacy_mappings_compact = {}

   # Python can't hash dicts or lists, so use the string representation as the hash key.
   def hash_key(mappings):
       return str(sorted(mappings.items(), key=itemgetter(0)))

   for lang, mappings in sorted(
       legacy_mappings_by_language.items(), key=itemgetter(0)
   ):
       key = hash_key(mappings)
       legacy_mappings_compact.setdefault(key, []).append(lang)

   for langs in legacy_mappings_compact.values():
       language_equal_to = (
           f"""Language().EqualTo("{lang}")""" for lang in sorted(langs)
       )
       cond = f""" ||\n{" " * len("  else if (")}""".join(language_equal_to)

       println(
           f"""
 else if ({cond}) {{
""".rstrip().lstrip("\n")
       )

       mappings = legacy_mappings_by_language[langs[0]]

       # Count the variant subtags to determine the sort order.
       def variant_size(m):
           (k, _) = m
           return len(k.split("-"))

       # Alias rules are applied by largest union size first.
       for size, mappings_by_size in groupby(
           sorted(mappings.items(), key=variant_size, reverse=True), key=variant_size
       ):
           # Convert grouper object to dict.
           mappings_by_size = dict(mappings_by_size)

           is_first = True
           chain_if = size == 1

           # Alias rules are applied in alphabetical order
           for variants, r_language in sorted(
               mappings_by_size.items(), key=itemgetter(0)
           ):
               sorted_variants = sorted(variants.split("-"))
               len_variants = len(sorted_variants)

               maybe_else = "else " if chain_if and not is_first else ""
               is_first = False

               for i, variant in enumerate(sorted_variants):
                   println(
                       f"""
   {"  " * i}{maybe_else}if (auto* {variant} = findVariant(mozilla::MakeStringSpan("{variant}"))) {{
""".rstrip().lstrip("\n")
                   )

               indent = "  " * len_variants

               println(
                   f"""
   {indent}removeVariant{"s" if len_variants > 1 else ""}({", ".join(sorted_variants)});
   {indent}SetLanguage("{r_language}");
   {indent}{"return true;" if not chain_if else ""}
""".rstrip().lstrip("\n")
               )

               for i in range(len_variants, 0, -1):
                   println(
                       f"""
   {"  " * (i - 1)}}}
""".rstrip().lstrip("\n")
                   )

       println(
           """
 }
""".rstrip().lstrip("\n")
       )

   println(
       """
 return true;
}"""
   )


def writeSignLanguageMappingsFunction(
   println, legacy_mappings, description, source, url
):
   """Writes a function definition that maps legacy sign language tags."""
   println("")
   writeMappingHeader(println, description, source, url)
   println(
       """\
bool mozilla::intl::Locale::SignLanguageMapping(LanguageSubtag& language,
                                               const RegionSubtag& region) {
 MOZ_ASSERT(language.EqualTo("sgn"));
 MOZ_ASSERT(IsStructurallyValidRegionTag(region.Span()));
 MOZ_ASSERT(IsCanonicallyCasedRegionTag(region.Span()));
""".rstrip()
   )

   region_mappings = {
       rg: lg
       for ((lang, _, rg, _), (lg, _, _, _)) in legacy_mappings.items()
       if lang == "sgn"
   }

   source_name = "region"
   target_name = "language"
   tag_maxlength = 3
   writeMappingsBinarySearchBody(
       println, source_name, target_name, region_mappings, tag_maxlength
   )

   println(
       """
}""".lstrip()
   )


def readSupplementalData(core_file):
   """Reads CLDR Supplemental Data and extracts information for Intl.js.

   Information extracted:
   - legacyMappings: mappings from legacy tags to preferred complete language tags
   - languageMappings: mappings from language subtags to preferred subtags
   - complexLanguageMappings: mappings from language subtags with complex rules
   - regionMappings: mappings from region subtags to preferred subtags
   - complexRegionMappings: mappings from region subtags with complex rules
   - variantMappings: mappings from variant subtags to preferred subtags
   - likelySubtags: likely subtags used for generating test data only
   Returns these mappings as dictionaries.
   """
   import xml.etree.ElementTree as ET

   # From Unicode BCP 47 locale identifier <https://unicode.org/reports/tr35/>.
   re_unicode_language_id = re.compile(
       r"""
       ^
       # unicode_language_id = unicode_language_subtag
       #     unicode_language_subtag = alpha{2,3} | alpha{5,8}
       (?P<language>[a-z]{2,3}|[a-z]{5,8})

       # (sep unicode_script_subtag)?
       #     unicode_script_subtag = alpha{4}
       (?:-(?P<script>[a-z]{4}))?

       # (sep unicode_region_subtag)?
       #     unicode_region_subtag = (alpha{2} | digit{3})
       (?:-(?P<region>([a-z]{2}|[0-9]{3})))?

       # (sep unicode_variant_subtag)*
       #     unicode_variant_subtag = (alphanum{5,8} | digit alphanum{3})
       (?P<variants>(-([a-z0-9]{5,8}|[0-9][a-z0-9]{3}))+)?
       $
       """,
       re.IGNORECASE | re.VERBOSE,
   )

   # CLDR uses "_" as the separator for some elements. Replace it with "-".
   def bcp47_id(cldr_id):
       return cldr_id.replace("_", "-")

   # Return the tuple (language, script, region, variants) and assert all
   # subtags are in canonical case.
   def bcp47_canonical(language, script, region, variants):
       # Canonical case for language subtags is lower case.
       assert language is None or language.lower() == language

       # Canonical case for script subtags is title case.
       assert script is None or script.title() == script

       # Canonical case for region subtags is upper case.
       assert region is None or region.upper() == region

       # Canonical case for variant subtags is lower case.
       assert variants is None or variants.lower() == variants

       return (language, script, region, variants[1:] if variants else None)

   # Language ids are interpreted as multi-maps in
   # <https://www.unicode.org/reports/tr35/#LocaleId_Canonicalization>.
   #
   # See UTS35, §Annex C, Definitions - 1. Multimap interpretation.
   def language_id_to_multimap(language_id):
       match = re_unicode_language_id.match(language_id)
       assert match is not None, (
           f"{language_id} invalid Unicode BCP 47 locale identifier"
       )

       canonical_language_id = bcp47_canonical(
           *match.group("language", "script", "region", "variants")
       )
       (language, _, _, _) = canonical_language_id

       # Normalize "und" language to None, but keep the rest as is.
       return (language if language != "und" else None,) + canonical_language_id[1:]

   rules = {}
   territory_exception_rules = {}

   tree = ET.parse(core_file.open("common/supplemental/supplementalMetadata.xml"))

   # Load the rules from supplementalMetadata.xml.
   #
   # See UTS35, §Annex C, Definitions - 2. Alias elements.
   # See UTS35, §Annex C, Preprocessing.
   for alias_name in [
       "languageAlias",
       "scriptAlias",
       "territoryAlias",
       "variantAlias",
   ]:
       for alias in tree.iterfind(".//" + alias_name):
           # Replace '_' by '-'.
           type = bcp47_id(alias.get("type"))
           replacement = bcp47_id(alias.get("replacement"))

           # Prefix with "und-".
           if alias_name != "languageAlias":
               type = "und-" + type

           # Discard all rules where the type is an invalid languageId.
           if re_unicode_language_id.match(type) is None:
               continue

           type = language_id_to_multimap(type)

           # Multiple, whitespace-separated territory replacements may be present.
           if alias_name == "territoryAlias" and " " in replacement:
               replacements = replacement.split(" ")
               replacement_list = [
                   language_id_to_multimap("und-" + r) for r in replacements
               ]

               assert type not in territory_exception_rules, (
                   f"Duplicate alias rule: {type}"
               )

               territory_exception_rules[type] = replacement_list

               # The first element is the default territory replacement.
               replacement = replacements[0]

           # Prefix with "und-".
           if alias_name != "languageAlias":
               replacement = "und-" + replacement

           replacement = language_id_to_multimap(replacement)

           assert type not in rules, f"Duplicate alias rule: {type}"

           rules[type] = replacement

   # Helper class for pattern matching.
   class AnyClass:
       def __eq__(self, obj):
           return obj is not None

   Any = AnyClass()

   modified_rules = True
   loop_count = 0

   while modified_rules:
       modified_rules = False
       loop_count += 1

       # UTS 35 defines that canonicalization is applied until a fixed point has
       # been reached. This iterative application of the canonicalization algorithm
       # is only needed for a relatively small set of rules, so we can precompute
       # the transitive closure of all rules here and then perform a single pass
       # when canonicalizing language tags at runtime.
       transitive_rules = {}

       # Compute the transitive closure.
       # Any case which currently doesn't occur in the CLDR sources isn't supported
       # and will lead to throwing an error.
       for type, replacement in rules.items():
           (language, script, region, variants) = type
           (r_language, r_script, r_region, r_variants) = replacement

           for i_type, i_replacement in rules.items():
               (i_language, i_script, i_region, i_variants) = i_type
               (i_r_language, i_r_script, i_r_region, i_r_variants) = i_replacement

               if i_language is not None and i_language == r_language:
                   # This case currently only occurs when neither script nor region
                   # subtags are present. A single variant subtags may be present
                   # in |type|. And |i_type| definitely has a single variant subtag.
                   # Should this ever change, update this code accordingly.
                   assert type in {
                       (Any, None, None, None),
                       (Any, None, None, Any),
                   }
                   assert replacement == (Any, None, None, None)
                   assert i_type == (Any, None, None, Any)
                   assert i_replacement == (Any, None, None, None)

                   # This case happens for the rules
                   #   "zh-guoyu -> zh",
                   #   "zh-hakka -> hak", and
                   #   "und-hakka -> und".
                   # Given the possible input "zh-guoyu-hakka", the first rule will
                   # change it to "zh-hakka", and then the second rule can be
                   # applied. (The third rule isn't applied ever.)
                   #
                   # Let's assume there's a hypothetical rule
                   #   "zh-aaaaa" -> "en"
                   # And we have the input "zh-aaaaa-hakka", then "zh-aaaaa -> en"
                   # is applied before "zh-hakka -> hak", because rules are sorted
                   # alphabetically. That means the overall result is "en":
                   # "zh-aaaaa-hakka" is first canonicalized to "en-hakka" and then
                   # "hakka" is removed through the third rule.
                   #
                   # No current rule requires to handle this special case, so we
                   # don't yet support it.
                   assert variants is None or variants <= i_variants

                   # Combine all variants and remove duplicates.
                   vars = set(
                       i_variants.split("-")
                       + (variants.split("-") if variants else [])
                   )

                   # Add the variants alphabetically sorted.
                   n_type = (language, None, None, "-".join(sorted(vars)))

                   assert (
                       n_type not in transitive_rules
                       or transitive_rules[n_type] == i_replacement
                   )
                   transitive_rules[n_type] = i_replacement

                   continue

               if i_script is not None and i_script == r_script:
                   # This case currently doesn't occur, so we don't yet support it.
                   raise ValueError(
                       f"{type} -> {replacement} :: {i_type} -> {i_replacement}"
                   )
               if i_region is not None and i_region == r_region:
                   # This case currently only applies for sign language
                   # replacements. Similar to the language subtag case any other
                   # combination isn't currently supported.
                   assert type == (None, None, Any, None)
                   assert replacement == (None, None, Any, None)
                   assert i_type == ("sgn", None, Any, None)
                   assert i_replacement == (Any, None, None, None)

                   n_type = ("sgn", None, region, None)

                   assert n_type not in transitive_rules
                   transitive_rules[n_type] = i_replacement

                   continue

               if i_variants is not None and i_variants == r_variants:
                   # This case currently doesn't occur, so we don't yet support it.
                   raise ValueError(
                       f"{type} -> {replacement} :: {i_type} -> {i_replacement}"
                   )

       # Ensure there are no contradicting rules.
       assert all(
           rules[type] == replacement
           for (type, replacement) in transitive_rules.items()
           if type in rules
       )

       # If |transitive_rules| is not a subset of |rules|, new rules will be added.
       modified_rules = not (transitive_rules.keys() <= rules.keys())

       # Ensure we only have to iterate more than once for the "guoyo-{hakka,xiang}"
       # case. Failing this assertion means either there's a bug when computing the
       # stop condition of this loop or a new kind of legacy language tags was added.
       if modified_rules and loop_count > 1:
           new_rules = {k for k in transitive_rules.keys() if k not in rules}
           for k in new_rules:
               assert k in {
                   (Any, None, None, "guoyu-hakka"),
                   (Any, None, None, "guoyu-xiang"),
               }

       # Merge the transitive rules.
       rules.update(transitive_rules)

   # Computes the size of the union of all field value sets.
   def multi_map_size(locale_id):
       (language, script, region, variants) = locale_id

       return (
           (1 if language is not None else 0)
           + (1 if script is not None else 0)
           + (1 if region is not None else 0)
           + (len(variants.split("-")) if variants is not None else 0)
       )

   # Dictionary of legacy mappings, contains raw rules, e.g.
   # (None, None, None, "hepburn-heploc") -> (None, None, None, "alalc97").
   legacy_mappings = {}

   # Dictionary of simple language subtag mappings, e.g. "in" -> "id".
   language_mappings = {}

   # Dictionary of complex language subtag mappings, modifying more than one
   # subtag, e.g. "sh" -> ("sr", "Latn", None) and "cnr" -> ("sr", None, "ME").
   complex_language_mappings = {}

   # Dictionary of simple script subtag mappings, e.g. "Qaai" -> "Zinh".
   script_mappings = {}

   # Dictionary of simple region subtag mappings, e.g. "DD" -> "DE".
   region_mappings = {}

   # Dictionary of complex region subtag mappings, containing more than one
   # replacement, e.g. "SU" -> ("RU", ["AM", "AZ", "BY", ...]).
   complex_region_mappings = {}

   # Dictionary of aliased variant subtags to a tuple of preferred replacement
   # type and replacement, e.g. "arevela" -> ("language", "hy") or
   # "aaland" -> ("region", "AX") or "heploc" -> ("variant", "alalc97").
   variant_mappings = {}

   # Preprocess all rules so we can perform a single lookup per subtag at runtime.
   for type, replacement in rules.items():
       (language, script, region, variants) = type
       (r_language, r_script, r_region, r_variants) = replacement

       type_map_size = multi_map_size(type)

       # Most mappings are one-to-one and can be encoded through lookup tables.
       if type_map_size == 1:
           if language is not None:
               assert r_language is not None, "Can't remove a language subtag"

               # We don't yet support this case.
               assert r_variants is None, (
                   f"Unhandled variant replacement in language alias: {replacement}"
               )

               if replacement == (Any, None, None, None):
                   language_mappings[language] = r_language
               else:
                   complex_language_mappings[language] = replacement[:-1]
           elif script is not None:
               # We don't support removing script subtags.
               assert r_script is not None, (
                   f"Can't remove a script subtag: {replacement}"
               )

               # We only support one-to-one script mappings for now.
               assert replacement == (
                   None,
                   Any,
                   None,
                   None,
               ), f"Unhandled replacement in script alias: {replacement}"

               script_mappings[script] = r_script
           elif region is not None:
               # We don't support removing region subtags.
               assert r_region is not None, (
                   f"Can't remove a region subtag: {replacement}"
               )

               # We only support one-to-one region mappings for now.
               assert replacement == (
                   None,
                   None,
                   Any,
                   None,
               ), f"Unhandled replacement in region alias: {replacement}"

               if type not in territory_exception_rules:
                   region_mappings[region] = r_region
               else:
                   complex_region_mappings[region] = [
                       r_region
                       for (_, _, r_region, _) in territory_exception_rules[type]
                   ]
           else:
               assert variants is not None
               assert len(variants.split("-")) == 1

               # We only support one-to-one variant mappings for now.
               assert multi_map_size(replacement) <= 1, (
                   f"Unhandled replacement in variant alias: {replacement}"
               )

               if r_language is not None:
                   variant_mappings[variants] = ("language", r_language)
               elif r_script is not None:
                   variant_mappings[variants] = ("script", r_script)
               elif r_region is not None:
                   variant_mappings[variants] = ("region", r_region)
               elif r_variants is not None:
                   assert len(r_variants.split("-")) == 1
                   variant_mappings[variants] = ("variant", r_variants)
               else:
                   variant_mappings[variants] = None
       else:
           # Alias rules which have multiple input fields must be processed
           # first. This applies only to a handful of rules, so our generated
           # code adds fast paths to skip these rules in the common case.

           # Case 1: Language and at least one variant subtag.
           if language is not None and variants is not None:
               pass

           # Case 2: Sign language and a region subtag.
           elif language == "sgn" and region is not None:
               pass

           # Case 3: "hepburn-heploc" to "alalc97" canonicalization.
           elif (
               language is None
               and variants is not None
               and len(variants.split("-")) == 2
           ):
               pass

           # Any other combination is currently unsupported.
           else:
               raise ValueError(f"{type} -> {replacement}")

           legacy_mappings[type] = replacement

   tree = ET.parse(core_file.open("common/supplemental/likelySubtags.xml"))

   likely_subtags = {}

   for likely_subtag in tree.iterfind(".//likelySubtag"):
       from_tag = bcp47_id(likely_subtag.get("from"))
       from_match = re_unicode_language_id.match(from_tag)
       assert from_match is not None, (
           f"{from_tag} invalid Unicode BCP 47 locale identifier"
       )
       assert from_match.group("variants") is None, (
           f"unexpected variant subtags in {from_tag}"
       )

       to_tag = bcp47_id(likely_subtag.get("to"))
       to_match = re_unicode_language_id.match(to_tag)
       assert to_match is not None, (
           f"{to_tag} invalid Unicode BCP 47 locale identifier"
       )
       assert to_match.group("variants") is None, (
           f"unexpected variant subtags in {to_tag}"
       )

       from_canonical = bcp47_canonical(
           *from_match.group("language", "script", "region", "variants")
       )

       to_canonical = bcp47_canonical(
           *to_match.group("language", "script", "region", "variants")
       )

       # Remove the empty variant subtags.
       from_canonical = from_canonical[:-1]
       to_canonical = to_canonical[:-1]

       likely_subtags[from_canonical] = to_canonical

   complex_region_mappings_final = {}

   for deprecated_region, replacements in complex_region_mappings.items():
       # Find all likely subtag entries which don't already contain a region
       # subtag and whose target region is in the list of replacement regions.
       region_likely_subtags = [
           (from_language, from_script, to_region)
           for (
               (from_language, from_script, from_region),
               (_, _, to_region),
           ) in likely_subtags.items()
           if from_region is None and to_region in replacements
       ]

       # The first replacement entry is the default region.
       default = replacements[0]

       # Find all likely subtag entries whose region matches the default region.
       default_replacements = {
           (language, script)
           for (language, script, region) in region_likely_subtags
           if region == default
       }

       # And finally find those entries which don't use the default region.
       # These are the entries we're actually interested in, because those need
       # to be handled specially when selecting the correct preferred region.
       non_default_replacements = [
           (language, script, region)
           for (language, script, region) in region_likely_subtags
           if (language, script) not in default_replacements
       ]

       # Remove redundant mappings.
       #
       # For example starting with CLDR 43, the deprecated region "SU" has the
       # following non-default replacement entries for "GE":
       # - ('sva', None, 'GE')
       # - ('sva', 'Cyrl', 'GE')
       # - ('sva', 'Latn', 'GE')
       #
       # The latter two entries are redundant, because they're already handled
       # by the first entry.
       non_default_replacements = [
           (language, script, region)
           for (language, script, region) in non_default_replacements
           if script is None
           or (language, None, region) not in non_default_replacements
       ]

       # If there are no non-default replacements, we can handle the region as
       # part of the simple region mapping.
       if non_default_replacements:
           complex_region_mappings_final[deprecated_region] = (
               default,
               non_default_replacements,
           )
       else:
           region_mappings[deprecated_region] = default

   return {
       "legacyMappings": legacy_mappings,
       "languageMappings": language_mappings,
       "complexLanguageMappings": complex_language_mappings,
       "scriptMappings": script_mappings,
       "regionMappings": region_mappings,
       "complexRegionMappings": complex_region_mappings_final,
       "variantMappings": variant_mappings,
       "likelySubtags": likely_subtags,
   }


def readUnicodeExtensions(core_file):
   import xml.etree.ElementTree as ET

   # Match all xml-files in the BCP 47 directory.
   bcpFileRE = re.compile(r"^common/bcp47/.+\.xml$")

   # https://www.unicode.org/reports/tr35/#Unicode_locale_identifier
   #
   # type = alphanum{3,8} (sep alphanum{3,8})* ;
   typeRE = re.compile(r"^[a-z0-9]{3,8}(-[a-z0-9]{3,8})*$")

   # https://www.unicode.org/reports/tr35/#Unicode_language_identifier
   #
   # unicode_region_subtag = alpha{2} ;
   alphaRegionRE = re.compile(r"^[A-Z]{2}$", re.IGNORECASE)

   # Mapping from Unicode extension types to dict of deprecated to
   # preferred values.
   mapping = {
       # Unicode BCP 47 U Extension
       "u": {},
       # Unicode BCP 47 T Extension
       "t": {},
   }

   def readBCP47File(file):
       tree = ET.parse(file)
       for keyword in tree.iterfind(".//keyword/key"):
           extension = keyword.get("extension", "u")
           assert extension in {"u", "t"}, f"unknown extension type: {extension}"

           extension_name = keyword.get("name")

           for type in keyword.iterfind("type"):
               # <https://unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files>:
               #
               # The key or type name used by Unicode locale extension with 'u' extension
               # syntax or the 't' extensions syntax. When alias below is absent, this name
               # can be also used with the old style "@key=type" syntax.
               name = type.get("name")

               # Ignore the special name:
               # - <https://unicode.org/reports/tr35/#CODEPOINTS>
               # - <https://unicode.org/reports/tr35/#REORDER_CODE>
               # - <https://unicode.org/reports/tr35/#RG_KEY_VALUE>
               # - <https://unicode.org/reports/tr35/#SCRIPT_CODE>
               # - <https://unicode.org/reports/tr35/#SUBDIVISION_CODE>
               # - <https://unicode.org/reports/tr35/#PRIVATE_USE>
               if name in (
                   "CODEPOINTS",
                   "REORDER_CODE",
                   "RG_KEY_VALUE",
                   "SCRIPT_CODE",
                   "SUBDIVISION_CODE",
                   "PRIVATE_USE",
               ):
                   continue

               # All other names should match the 'type' production.
               assert typeRE.match(name) is not None, (
                   f"{name} matches the 'type' production"
               )

               # <https://unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files>:
               #
               # The preferred value of the deprecated key, type or attribute element.
               # When a key, type or attribute element is deprecated, this attribute is
               # used for specifying a new canonical form if available.
               preferred = type.get("preferred")

               # <https://unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files>:
               #
               # The BCP 47 form is the canonical form, and recommended. Other aliases are
               # included only for backwards compatibility.
               alias = type.get("alias")

               # <https://unicode.org/reports/tr35/#Canonical_Unicode_Locale_Identifiers>
               #
               # Use the bcp47 data to replace keys, types, tfields, and tvalues by their
               # canonical forms. See Section 3.6.4 U Extension Data Files) and Section
               # 3.7.1 T Extension Data Files. The aliases are in the alias attribute
               # value, while the canonical is in the name attribute value.

               # 'preferred' contains the new preferred name, 'alias' the compatibility
               # name, but then there's this entry where 'preferred' and 'alias' are the
               # same. So which one to choose? Assume 'preferred' is the actual canonical
               # name.
               #
               # <type name="islamicc"
               #       description="Civil (algorithmic) Arabic calendar"
               #       deprecated="true"
               #       preferred="islamic-civil"
               #       alias="islamic-civil"/>

               if preferred is not None:
                   assert typeRE.match(preferred), preferred
                   mapping[extension].setdefault(extension_name, {})[name] = preferred

               if alias is not None:
                   for alias_name in alias.lower().split(" "):
                       # Ignore alias entries which don't match the 'type' production.
                       if typeRE.match(alias_name) is None:
                           continue

                       # See comment above when 'alias' and 'preferred' are both present.
                       if (
                           preferred is not None
                           and name in mapping[extension][extension_name]
                       ):
                           continue

                       # Skip over entries where 'name' and 'alias' are equal.
                       #
                       # <type name="pst8pdt"
                       #       description="POSIX style time zone for US Pacific Time"
                       #       alias="PST8PDT"
                       #       since="1.8"/>
                       if name == alias_name:
                           continue

                       mapping[extension].setdefault(extension_name, {})[
                           alias_name
                       ] = name

   def readSupplementalMetadata(file):
       # Find subdivision and region replacements.
       #
       # <https://www.unicode.org/reports/tr35/#Canonical_Unicode_Locale_Identifiers>
       #
       # Replace aliases in special key values:
       #   - If there is an 'sd' or 'rg' key, replace any subdivision alias
       #     in its value in the same way, using subdivisionAlias data.
       tree = ET.parse(file)
       for alias in tree.iterfind(".//subdivisionAlias"):
           type = alias.get("type")
           assert typeRE.match(type) is not None, (
               f"{type} matches the 'type' production"
           )

           # Take the first replacement when multiple ones are present.
           replacement = alias.get("replacement").split(" ")[0].lower()

           # Append "zzzz" if the replacement is a two-letter region code.
           if alphaRegionRE.match(replacement) is not None:
               replacement += "zzzz"

           # Assert the replacement is syntactically correct.
           assert typeRE.match(replacement) is not None, (
               f"replacement {replacement} matches the 'type' production"
           )

           # 'subdivisionAlias' applies to 'rg' and 'sd' keys.
           mapping["u"].setdefault("rg", {})[type] = replacement
           mapping["u"].setdefault("sd", {})[type] = replacement

   for name in core_file.namelist():
       if bcpFileRE.match(name):
           readBCP47File(core_file.open(name))

   readSupplementalMetadata(
       core_file.open("common/supplemental/supplementalMetadata.xml")
   )

   return {
       "unicodeMappings": mapping["u"],
       "transformMappings": mapping["t"],
   }


def writeCLDRLanguageTagData(println, data, url):
   """Writes the language tag data to the Intl data file."""

   println(generatedFileWarning)
   println("// Version: CLDR-{}".format(data["version"]))
   println(f"// URL: {url}")

   println(
       """
#include "mozilla/Assertions.h"
#include "mozilla/Span.h"
#include "mozilla/TextUtils.h"

#include <algorithm>
#include <cstdint>
#include <cstring>
#include <iterator>
#include <string>

#include "mozilla/intl/Locale.h"

using namespace mozilla::intl::LanguageTagLimits;

template <size_t Length, size_t TagLength, size_t SubtagLength>
static inline bool HasReplacement(
   const char (&subtags)[Length][TagLength],
   const mozilla::intl::LanguageTagSubtag<SubtagLength>& subtag) {
 MOZ_ASSERT(subtag.Length() == TagLength - 1,
            "subtag must have the same length as the list of subtags");

 const char* ptr = subtag.Span().data();
 return std::binary_search(std::begin(subtags), std::end(subtags), ptr,
                           [](const char* a, const char* b) {
                             return memcmp(a, b, TagLength - 1) < 0;
                           });
}

template <size_t Length, size_t TagLength, size_t SubtagLength>
static inline const char* SearchReplacement(
   const char (&subtags)[Length][TagLength], const char* (&aliases)[Length],
   const mozilla::intl::LanguageTagSubtag<SubtagLength>& subtag) {
 MOZ_ASSERT(subtag.Length() == TagLength - 1,
            "subtag must have the same length as the list of subtags");

 const char* ptr = subtag.Span().data();
 auto p = std::lower_bound(std::begin(subtags), std::end(subtags), ptr,
                           [](const char* a, const char* b) {
                             return memcmp(a, b, TagLength - 1) < 0;
                           });
 if (p != std::end(subtags) && memcmp(*p, ptr, TagLength - 1) == 0) {
   return aliases[std::distance(std::begin(subtags), p)];
 }
 return nullptr;
}

#ifdef DEBUG
static bool IsAsciiLowercaseAlphanumeric(char c) {
 return mozilla::IsAsciiLowercaseAlpha(c) || mozilla::IsAsciiDigit(c);
}

static bool IsAsciiLowercaseAlphanumericOrDash(char c) {
 return IsAsciiLowercaseAlphanumeric(c) || c == '-';
}

static bool IsCanonicallyCasedLanguageTag(mozilla::Span<const char> span) {
 return std::all_of(span.begin(), span.end(),
                    mozilla::IsAsciiLowercaseAlpha<char>);
}

static bool IsCanonicallyCasedScriptTag(mozilla::Span<const char> span) {
 return mozilla::IsAsciiUppercaseAlpha(span[0]) &&
        std::all_of(span.begin() + 1, span.end(),
                    mozilla::IsAsciiLowercaseAlpha<char>);
}

static bool IsCanonicallyCasedRegionTag(mozilla::Span<const char> span) {
 return std::all_of(span.begin(), span.end(),
                    mozilla::IsAsciiUppercaseAlpha<char>) ||
        std::all_of(span.begin(), span.end(), mozilla::IsAsciiDigit<char>);
}

static bool IsCanonicallyCasedVariantTag(mozilla::Span<const char> span) {
 return std::all_of(span.begin(), span.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedUnicodeKey(mozilla::Span<const char> key) {
 return std::all_of(key.begin(), key.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedUnicodeType(mozilla::Span<const char> type) {
 return std::all_of(type.begin(), type.end(),
                    IsAsciiLowercaseAlphanumericOrDash);
}

static bool IsCanonicallyCasedTransformKey(mozilla::Span<const char> key) {
 return std::all_of(key.begin(), key.end(), IsAsciiLowercaseAlphanumeric);
}

static bool IsCanonicallyCasedTransformType(mozilla::Span<const char> type) {
 return std::all_of(type.begin(), type.end(),
                    IsAsciiLowercaseAlphanumericOrDash);
}
#endif
""".rstrip()
   )

   source = "CLDR Supplemental Data, version {}".format(data["version"])
   legacy_mappings = data["legacyMappings"]
   language_mappings = data["languageMappings"]
   complex_language_mappings = data["complexLanguageMappings"]
   script_mappings = data["scriptMappings"]
   region_mappings = data["regionMappings"]
   complex_region_mappings = data["complexRegionMappings"]
   variant_mappings = data["variantMappings"]
   unicode_mappings = data["unicodeMappings"]
   transform_mappings = data["transformMappings"]

   # unicode_language_subtag = alpha{2,3} | alpha{5,8} ;
   language_maxlength = 8

   # unicode_script_subtag = alpha{4} ;
   script_maxlength = 4

   # unicode_region_subtag = (alpha{2} | digit{3}) ;
   region_maxlength = 3

   writeMappingsBinarySearch(
       println,
       "LanguageMapping",
       "LanguageSubtag&",
       "language",
       "IsStructurallyValidLanguageTag",
       "IsCanonicallyCasedLanguageTag",
       language_mappings,
       language_maxlength,
       "Mappings from language subtags to preferred values.",
       source,
       url,
   )
   writeMappingsBinarySearch(
       println,
       "ComplexLanguageMapping",
       "const LanguageSubtag&",
       "language",
       "IsStructurallyValidLanguageTag",
       "IsCanonicallyCasedLanguageTag",
       complex_language_mappings.keys(),
       language_maxlength,
       "Language subtags with complex mappings.",
       source,
       url,
   )
   writeMappingsBinarySearch(
       println,
       "ScriptMapping",
       "ScriptSubtag&",
       "script",
       "IsStructurallyValidScriptTag",
       "IsCanonicallyCasedScriptTag",
       script_mappings,
       script_maxlength,
       "Mappings from script subtags to preferred values.",
       source,
       url,
   )
   writeMappingsBinarySearch(
       println,
       "RegionMapping",
       "RegionSubtag&",
       "region",
       "IsStructurallyValidRegionTag",
       "IsCanonicallyCasedRegionTag",
       region_mappings,
       region_maxlength,
       "Mappings from region subtags to preferred values.",
       source,
       url,
   )
   writeMappingsBinarySearch(
       println,
       "ComplexRegionMapping",
       "const RegionSubtag&",
       "region",
       "IsStructurallyValidRegionTag",
       "IsCanonicallyCasedRegionTag",
       complex_region_mappings.keys(),
       region_maxlength,
       "Region subtags with complex mappings.",
       source,
       url,
   )

   writeComplexLanguageTagMappings(
       println,
       complex_language_mappings,
       "Language subtags with complex mappings.",
       source,
       url,
   )
   writeComplexRegionTagMappings(
       println,
       complex_region_mappings,
       "Region subtags with complex mappings.",
       source,
       url,
   )

   writeVariantTagMappings(
       println,
       variant_mappings,
       "Mappings from variant subtags to preferred values.",
       source,
       url,
   )

   writeLegacyMappingsFunction(
       println, legacy_mappings, "Canonicalize legacy locale identifiers.", source, url
   )

   writeSignLanguageMappingsFunction(
       println, legacy_mappings, "Mappings from legacy sign languages.", source, url
   )

   writeUnicodeExtensionsMappings(println, unicode_mappings, "Unicode")
   writeUnicodeExtensionsMappings(println, transform_mappings, "Transform")


def writeCLDRLanguageTagLikelySubtagsTest(println, data, url):
   """Writes the likely-subtags test file."""

   println(generatedFileWarning)

   source = "CLDR Supplemental Data, version {}".format(data["version"])
   language_mappings = data["languageMappings"]
   complex_language_mappings = data["complexLanguageMappings"]
   script_mappings = data["scriptMappings"]
   region_mappings = data["regionMappings"]
   complex_region_mappings = data["complexRegionMappings"]
   likely_subtags = data["likelySubtags"]

   def bcp47(tag):
       (language, script, region) = tag
       return "{}{}{}".format(
           language, "-" + script if script else "", "-" + region if region else ""
       )

   def canonical(tag):
       (language, script, region) = tag

       # Map deprecated language subtags.
       if language in language_mappings:
           language = language_mappings[language]
       elif language in complex_language_mappings:
           (language2, script2, region2) = complex_language_mappings[language]
           (language, script, region) = (
               language2,
               script if script else script2,
               region if region else region2,
           )

       # Map deprecated script subtags.
       if script in script_mappings:
           script = script_mappings[script]

       # Map deprecated region subtags.
       if region in region_mappings:
           region = region_mappings[region]
       else:
           # Assume no complex region mappings are needed for now.
           assert region not in complex_region_mappings, (
               f"unexpected region with complex mappings: {region}"
           )

       return (language, script, region)

   # https://unicode.org/reports/tr35/#Likely_Subtags

   def addLikelySubtags(tag):
       # Step 1: Canonicalize.
       (language, script, region) = canonical(tag)
       if script == "Zzzz":
           script = None
       if region == "ZZ":
           region = None

       # Step 2: Lookup.
       searches = (
           (language, script, region),
           (language, script, None),
           (language, None, region),
           (language, None, None),
       )
       search = next(search for search in searches if search in likely_subtags)

       (language_s, script_s, region_s) = search
       (language_m, script_m, region_m) = likely_subtags[search]

       # Step 3: Return.
       return (
           language if language != language_s else language_m,
           script if script != script_s else script_m,
           region if region != region_s else region_m,
       )

   # https://unicode.org/reports/tr35/#Likely_Subtags
   def removeLikelySubtags(tag):
       # Step 1: Add likely subtags.
       max = addLikelySubtags(tag)

       # Step 2: Remove variants (doesn't apply here).

       # Step 3: Find a match.
       (language, script, region) = max
       for trial in (
           (language, None, None),
           (language, None, region),
           (language, script, None),
       ):
           if addLikelySubtags(trial) == max:
               return trial

       # Step 4: Return maximized if no match found.
       return max

   def likely_canonical(from_tag, to_tag):
       # Canonicalize the input tag.
       from_tag = canonical(from_tag)

       # Update the expected result if necessary.
       if from_tag in likely_subtags:
           to_tag = likely_subtags[from_tag]

       # Canonicalize the expected output.
       to_canonical = canonical(to_tag)

       # Sanity check: This should match the result of |addLikelySubtags|.
       assert to_canonical == addLikelySubtags(from_tag)

       return to_canonical

   # |likely_subtags| contains non-canonicalized tags, so canonicalize it first.
   likely_subtags_canonical = {
       k: likely_canonical(k, v) for (k, v) in likely_subtags.items()
   }

   # Add test data for |Intl.Locale.prototype.maximize()|.
   writeMappingsVar(
       println,
       {bcp47(k): bcp47(v) for (k, v) in likely_subtags_canonical.items()},
       "maxLikelySubtags",
       "Extracted from likelySubtags.xml.",
       source,
       url,
   )

   # Use the maximalized tags as the input for the remove likely-subtags test.
   minimized = {
       tag: removeLikelySubtags(tag) for tag in likely_subtags_canonical.values()
   }

   # Add test data for |Intl.Locale.prototype.minimize()|.
   writeMappingsVar(
       println,
       {bcp47(k): bcp47(v) for (k, v) in minimized.items()},
       "minLikelySubtags",
       "Extracted from likelySubtags.xml.",
       source,
       url,
   )

   println(
       """
for (let [tag, maximal] of Object.entries(maxLikelySubtags)) {
   assertEq(new Intl.Locale(tag).maximize().toString(), maximal);
}"""
   )

   println(
       """
for (let [tag, minimal] of Object.entries(minLikelySubtags)) {
   assertEq(new Intl.Locale(tag).minimize().toString(), minimal);
}"""
   )

   println(
       """
if (typeof reportCompare === "function")
   reportCompare(0, 0);"""
   )


def readCLDRVersionFromICU():
   icuDir = os.path.join(topsrcdir, "intl/icu/source")
   if not os.path.isdir(icuDir):
       raise RuntimeError(f"not a directory: {icuDir}")

   reVersion = re.compile(r'\s*cldrVersion\{"(\d+(?:\.\d+)?)"\}')

   for line in flines(os.path.join(icuDir, "data/misc/supplementalData.txt")):
       m = reVersion.match(line)
       if m:
           version = m.group(1)
           break

   if version is None:
       raise RuntimeError("can't resolve CLDR version")

   return version


def updateCLDRLangTags(args):
   """Update the LanguageTagGenerated.cpp file."""
   version = args.version
   url = args.url
   out = args.out
   filename = args.file

   # Determine current CLDR version from ICU.
   if version is None:
       version = readCLDRVersionFromICU()

   url = url.replace("<VERSION>", version)

   print("Arguments:")
   print("\tCLDR version: %s" % version)
   print("\tDownload url: %s" % url)
   if filename is not None:
       print("\tLocal CLDR common.zip file: %s" % filename)
   print("\tOutput file: %s" % out)
   print("")

   data = {
       "version": version,
   }

   def readFiles(cldr_file):
       with ZipFile(cldr_file) as zip_file:
           data.update(readSupplementalData(zip_file))
           data.update(readUnicodeExtensions(zip_file))

   print("Processing CLDR data...")
   if filename is not None:
       print("Always make sure you have the newest CLDR common.zip!")
       with open(filename, "rb") as cldr_file:
           readFiles(cldr_file)
   else:
       print("Downloading CLDR common.zip...")
       with closing(urlopen(url)) as cldr_file:
           cldr_data = io.BytesIO(cldr_file.read())
           readFiles(cldr_data)

   print("Writing Intl data...")
   with open(out, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       writeCLDRLanguageTagData(println, data, url)

   print("Writing Intl test data...")
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   test_file = os.path.join(
       js_src_builtin_intl_dir,
       "../../tests/non262/Intl/Locale/likely-subtags-generated.js",
   )
   with open(test_file, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println("// |reftest| skip-if(!this.hasOwnProperty('Intl'))")
       writeCLDRLanguageTagLikelySubtagsTest(println, data, url)


def flines(filepath, encoding="utf-8"):
   """Open filepath and iterate over its content."""
   with open(filepath, encoding=encoding) as f:
       yield from f


@total_ordering
class Zone:
   """Time zone with optional file name."""

   def __init__(self, name, filename=""):
       self.name = name
       self.filename = filename

   def __eq__(self, other):
       return hasattr(other, "name") and self.name == other.name

   def __lt__(self, other):
       return self.name < other.name

   def __hash__(self):
       return hash(self.name)

   def __str__(self):
       return self.name

   def __repr__(self):
       return self.name


class TzDataDir:
   """tzdata source from a directory."""

   def __init__(self, obj):
       self.name = partial(os.path.basename, obj)
       self.resolve = partial(os.path.join, obj)
       self.basename = os.path.basename
       self.isfile = os.path.isfile
       self.listdir = partial(os.listdir, obj)
       self.readlines = flines


class TzDataFile:
   """tzdata source from a file (tar or gzipped)."""

   def __init__(self, obj):
       self.name = lambda: os.path.splitext(
           os.path.splitext(os.path.basename(obj))[0]
       )[0]
       self.resolve = obj.getmember
       self.basename = attrgetter("name")
       self.isfile = tarfile.TarInfo.isfile
       self.listdir = obj.getnames
       self.readlines = partial(self._tarlines, obj)

   def _tarlines(self, tar, m):
       with closing(tar.extractfile(m)) as f:
           for line in f:
               yield line.decode("utf-8")


def validateTimeZones(zones, links):
   """Validate the zone and link entries."""
   linkZones = set(links.keys())
   intersect = linkZones.intersection(zones)
   if intersect:
       raise RuntimeError("Links also present in zones: %s" % intersect)

   zoneNames = {z.name for z in zones}
   linkTargets = set(links.values())
   if not linkTargets.issubset(zoneNames):
       raise RuntimeError(
           "Link targets not found: %s" % linkTargets.difference(zoneNames)
       )


def partition(iterable, *predicates):
   def innerPartition(pred, it):
       it1, it2 = tee(it)
       return (filter(pred, it1), filterfalse(pred, it2))

   if len(predicates) == 0:
       return iterable
   (left, right) = innerPartition(predicates[0], iterable)
   if len(predicates) == 1:
       return (left, right)
   return tuple([left] + list(partition(right, *predicates[1:])))


def listIANAFiles(tzdataDir):
   def isTzFile(d, m, f):
       return m(f) and d.isfile(d.resolve(f))

   return filter(
       partial(isTzFile, tzdataDir, re.compile("^[a-z0-9]+$").match),
       tzdataDir.listdir(),
   )


def readIANAFiles(tzdataDir, files):
   """Read all IANA time zone files from the given iterable."""
   nameSyntax = r"[\w/+\-]+"
   pZone = re.compile(r"Zone\s+(?P<name>%s)\s+.*" % nameSyntax)
   pLink = re.compile(
       r"(#PACKRATLIST\s+zone.tab\s+)?Link\s+(?P<target>%s)\s+(?P<name>%s)(?:\s+#.*)?"
       % (nameSyntax, nameSyntax)
   )

   def createZone(line, fname):
       match = pZone.match(line)
       name = match.group("name")
       return Zone(name, fname)

   def createLink(line, fname):
       match = pLink.match(line)
       (name, target) = match.group("name", "target")
       return (Zone(name, fname), target)

   zones = set()
   links = dict()
   packrat_links = dict()
   for filename in files:
       filepath = tzdataDir.resolve(filename)
       for line in tzdataDir.readlines(filepath):
           if line.startswith("Zone"):
               zones.add(createZone(line, filename))
           if line.startswith("Link"):
               (link, target) = createLink(line, filename)
               links[link] = target
           if line.startswith("#PACKRATLIST zone.tab Link"):
               (link, target) = createLink(line, filename)
               packrat_links[link] = target

   return (zones, links, packrat_links)


def readIANATimeZones(tzdataDir, ignoreFactory):
   """Read the IANA time zone information from `tzdataDir`."""

   files_to_ignore = ["backzone"]

   # Ignore the placeholder time zone "Factory".
   if ignoreFactory:
       files_to_ignore.append("factory")

   tzfiles = (file for file in listIANAFiles(tzdataDir) if file not in files_to_ignore)

   # Read zone and link infos.
   (zones, links, _) = readIANAFiles(tzdataDir, tzfiles)

   validateTimeZones(zones, links)

   return (zones, links)


def readICUResourceFile(filename):
   """Read an ICU resource file.

   Yields (<table-name>, <startOrEnd>, <value>) for each table.
   """

   numberValue = r"-?\d+"
   stringValue = r'".+?"'

   def asVector(val):
       return r"%s(?:\s*,\s*%s)*" % (val, val)

   numberVector = asVector(numberValue)
   stringVector = asVector(stringValue)

   reNumberVector = re.compile(numberVector)
   reStringVector = re.compile(stringVector)
   reNumberValue = re.compile(numberValue)
   reStringValue = re.compile(stringValue)

   def parseValue(value):
       m = reNumberVector.match(value)
       if m:
           return [int(v) for v in reNumberValue.findall(value)]
       m = reStringVector.match(value)
       if m:
           return [v[1:-1] for v in reStringValue.findall(value)]
       raise RuntimeError("unknown value type: %s" % value)

   def extractValue(values):
       if len(values) == 0:
           return None
       if len(values) == 1:
           return values[0]
       return values

   def line(*args):
       maybeMultiComments = r"(?:/\*[^*]*\*/)*"
       maybeSingleComment = r"(?://.*)?"
       lineStart = "^%s" % maybeMultiComments
       lineEnd = r"%s\s*%s$" % (maybeMultiComments, maybeSingleComment)
       return re.compile(r"\s*".join(chain([lineStart], args, [lineEnd])))

   tableName = r'(?P<quote>"?)(?P<name>.+?)(?P=quote)'
   tableValue = r"(?P<value>%s|%s)" % (numberVector, stringVector)

   reStartTable = line(tableName, r"\{")
   reEndTable = line(r"\}")
   reSingleValue = line(r",?", tableValue, r",?")
   reCompactTable = line(tableName, r"\{", tableValue, r"\}")
   reEmptyLine = line()

   tables = []

   def currentTable():
       return "|".join(tables)

   values = []
   for line in flines(filename, "utf-8-sig"):
       line = line.strip()
       if line == "":
           continue

       m = reEmptyLine.match(line)
       if m:
           continue

       m = reStartTable.match(line)
       if m:
           assert len(values) == 0
           tables.append(m.group("name"))
           continue

       m = reEndTable.match(line)
       if m:
           yield (currentTable(), extractValue(values))
           tables.pop()
           values = []
           continue

       m = reCompactTable.match(line)
       if m:
           assert len(values) == 0
           tables.append(m.group("name"))
           yield (currentTable(), extractValue(parseValue(m.group("value"))))
           tables.pop()
           continue

       m = reSingleValue.match(line)
       if m and tables:
           values.extend(parseValue(m.group("value")))
           continue

       raise RuntimeError("unknown entry: %s" % line)


def readICUTimeZonesFromTimezoneTypes(icuTzDir):
   """Read the ICU time zone information from `icuTzDir`/timezoneTypes.txt
   and returns the tuple (zones, links).
   """
   typeMapTimeZoneKey = "timezoneTypes:table(nofallback)|typeMap|timezone|"
   typeAliasTimeZoneKey = "timezoneTypes:table(nofallback)|typeAlias|timezone|"

   def toTimeZone(name):
       return Zone(name.replace(":", "/"))

   zones = set()
   links = dict()

   for name, value in readICUResourceFile(os.path.join(icuTzDir, "timezoneTypes.txt")):
       if name.startswith(typeMapTimeZoneKey):
           zones.add(toTimeZone(name[len(typeMapTimeZoneKey) :]))
       if name.startswith(typeAliasTimeZoneKey):
           links[toTimeZone(name[len(typeAliasTimeZoneKey) :])] = value

   validateTimeZones(zones, links)

   return (zones, links)


def readICUTimeZonesFromZoneInfo(icuTzDir):
   """Read the ICU time zone information from `icuTzDir`/zoneinfo64.txt
   and returns the tuple (zones, links).
   """
   zoneKey = "zoneinfo64:table(nofallback)|Zones:array|:table"
   linkKey = "zoneinfo64:table(nofallback)|Zones:array|:int"
   namesKey = "zoneinfo64:table(nofallback)|Names"

   tzId = 0
   tzLinks = dict()
   tzNames = []

   for name, value in readICUResourceFile(os.path.join(icuTzDir, "zoneinfo64.txt")):
       if name == zoneKey:
           tzId += 1
       elif name == linkKey:
           tzLinks[tzId] = int(value)
           tzId += 1
       elif name == namesKey:
           tzNames.extend(value)

   links = {Zone(tzNames[zone]): tzNames[target] for (zone, target) in tzLinks.items()}
   zones = {Zone(v) for v in tzNames if Zone(v) not in links}

   validateTimeZones(zones, links)

   return (zones, links)


def readICUTimeZones(icuDir, icuTzDir, ignoreFactory):
   # zoneinfo64.txt contains the supported time zones by ICU. This data is
   # generated from tzdata files, it doesn't include "backzone" in stock ICU.
   (zoneinfoZones, zoneinfoLinks) = readICUTimeZonesFromZoneInfo(icuTzDir)

   # timezoneTypes.txt contains the canonicalization information for ICU. This
   # data is generated from CLDR files. It includes data about time zones from
   # tzdata's "backzone" file.
   (typesZones, typesLinks) = readICUTimeZonesFromTimezoneTypes(icuTzDir)

   # Remove the placeholder time zone "Factory".
   # See also <https://github.com/eggert/tz/blob/master/factory>.
   if ignoreFactory:
       assert Zone("Factory") in zoneinfoZones
       assert Zone("Factory") not in zoneinfoLinks
       assert Zone("Factory") not in typesZones
       assert Zone("Factory") in typesLinks

       zoneinfoZones.remove(Zone("Factory"))
       del typesLinks[Zone("Factory")]

   # Remove the ICU placeholder time zone "Etc/Unknown".
   # See also <https://unicode.org/reports/tr35/#Time_Zone_Identifiers>.
   for zones in (zoneinfoZones, typesZones):
       zones.remove(Zone("Etc/Unknown"))

   # Remove any outdated ICU links.
   for links in (zoneinfoLinks, typesLinks):
       for zone in otherICULegacyLinks().keys():
           if zone not in links:
               raise KeyError(f"Can't remove non-existent link from '{zone}'")
           del links[zone]

   # Information in zoneinfo64 should be a superset of timezoneTypes.
   def inZoneInfo64(zone):
       return zone in zoneinfoZones or zone in zoneinfoLinks

   notFoundInZoneInfo64 = [zone for zone in typesZones if not inZoneInfo64(zone)]
   if notFoundInZoneInfo64:
       raise RuntimeError(
           "Missing time zones in zoneinfo64.txt: %s" % notFoundInZoneInfo64
       )

   notFoundInZoneInfo64 = [
       zone for zone in typesLinks.keys() if not inZoneInfo64(zone)
   ]
   if notFoundInZoneInfo64:
       raise RuntimeError(
           "Missing time zones in zoneinfo64.txt: %s" % notFoundInZoneInfo64
       )

   # zoneinfo64.txt only defines the supported time zones by ICU, the canonicalization
   # rules are defined through timezoneTypes.txt. Merge both to get the actual zones
   # and links used by ICU.
   icuZones = set(
       chain(
           (zone for zone in zoneinfoZones if zone not in typesLinks),
           (zone for zone in typesZones),
       )
   )
   icuLinks = dict(
       chain(
           (
               (zone, target)
               for (zone, target) in zoneinfoLinks.items()
               if zone not in typesZones
           ),
           ((zone, target) for (zone, target) in typesLinks.items()),
       )
   )

   return (icuZones, icuLinks)


def readICULegacyZones(icuDir):
   """Read the ICU legacy time zones from `icuTzDir`/tools/tzcode/icuzones
   and returns the tuple (zones, links).
   """
   tzdir = TzDataDir(os.path.join(icuDir, "tools/tzcode"))

   # Per spec we must recognize only IANA time zones and links, but ICU
   # recognizes various legacy, non-IANA time zones and links. Compute these
   # non-IANA time zones and links.

   # Most legacy, non-IANA time zones and links are in the icuzones file.
   (zones, links, _) = readIANAFiles(tzdir, ["icuzones"])

   # Remove the ICU placeholder time zone "Etc/Unknown".
   # See also <https://unicode.org/reports/tr35/#Time_Zone_Identifiers>.
   zones.remove(Zone("Etc/Unknown"))

   # A handful of non-IANA zones/links are not in icuzones and must be added
   # manually so that we won't invoke ICU with them.
   for zone, target in otherICULegacyLinks().items():
       if zone in links:
           if links[zone] != target:
               raise KeyError(
                   f"Can't overwrite link '{zone} -> {links[zone]}' with '{target}'"
               )
           else:
               print(
                   f"Info: Link '{zone} -> {target}' can be removed from otherICULegacyLinks()"
               )
       links[zone] = target

   return (zones, links)


def otherICULegacyLinks():
   """The file `icuTzDir`/tools/tzcode/icuzones contains all ICU legacy time
   zones with the exception of time zones which are removed by IANA after an
   ICU release.

   For example ICU 67 uses tzdata2018i, but tzdata2020b removed the link from
   "US/Pacific-New" to "America/Los_Angeles". ICU standalone tzdata updates
   don't include modified icuzones files, so we must manually record any IANA
   modifications here.

   After an ICU update, we can remove any no longer needed entries from this
   function by checking if the relevant entries are now included in icuzones.
   """

   return {
       # Current ICU is up-to-date with IANA, so this dict is empty.
   }


def icuTzDataVersion(icuTzDir):
   """Read the ICU time zone version from `icuTzDir`/zoneinfo64.txt."""

   def searchInFile(pattern, f):
       p = re.compile(pattern)
       for line in flines(f, "utf-8-sig"):
           m = p.search(line)
           if m:
               return m.group(1)
       return None

   zoneinfo = os.path.join(icuTzDir, "zoneinfo64.txt")
   if not os.path.isfile(zoneinfo):
       raise RuntimeError("file not found: %s" % zoneinfo)
   version = searchInFile(r"^//\s+tz version:\s+([0-9]{4}[a-z])$", zoneinfo)
   if version is None:
       raise RuntimeError(
           "%s does not contain a valid tzdata version string" % zoneinfo
       )
   return version


def findIncorrectICUZones(ianaZones, ianaLinks, icuZones, icuLinks):
   """Find incorrect ICU zone entries."""

   def isIANATimeZone(zone):
       return zone in ianaZones or zone in ianaLinks

   def isICUTimeZone(zone):
       return zone in icuZones or zone in icuLinks

   def isICULink(zone):
       return zone in icuLinks

   # All IANA zones should be present in ICU.
   missingTimeZones = [zone for zone in ianaZones if not isICUTimeZone(zone)]
   if missingTimeZones:
       raise RuntimeError(
           "Not all zones are present in ICU, did you forget "
           "to run intl/update-tzdata.sh? %s" % missingTimeZones
       )

   # Zones which are only present in ICU?
   additionalTimeZones = [zone for zone in icuZones if not isIANATimeZone(zone)]
   if additionalTimeZones:
       raise RuntimeError(
           "Additional zones present in ICU, did you forget "
           "to run intl/update-tzdata.sh? %s" % additionalTimeZones
       )

   # Zones which are marked as links in ICU.
   result = ((zone, icuLinks[zone]) for zone in ianaZones if isICULink(zone))

   # Remove unnecessary UTC mappings.
   utcnames = ["Etc/UTC", "Etc/UCT", "Etc/GMT"]
   result = ((zone, target) for (zone, target) in result if zone.name not in utcnames)

   return sorted(result, key=itemgetter(0))


def findIncorrectICULinks(ianaZones, ianaLinks, icuZones, icuLinks):
   """Find incorrect ICU link entries."""

   def isIANATimeZone(zone):
       return zone in ianaZones or zone in ianaLinks

   def isICUTimeZone(zone):
       return zone in icuZones or zone in icuLinks

   def isICULink(zone):
       return zone in icuLinks

   def isICUZone(zone):
       return zone in icuZones

   # All links should be present in ICU.
   missingTimeZones = [zone for zone in ianaLinks.keys() if not isICUTimeZone(zone)]
   if missingTimeZones:
       raise RuntimeError(
           "Not all zones are present in ICU, did you forget "
           "to run intl/update-tzdata.sh? %s" % missingTimeZones
       )

   # Links which are only present in ICU?
   additionalTimeZones = [zone for zone in icuLinks.keys() if not isIANATimeZone(zone)]
   if additionalTimeZones:
       raise RuntimeError(
           "Additional links present in ICU, did you forget "
           "to run intl/update-tzdata.sh? %s" % additionalTimeZones
       )

   result = chain(
       # IANA links which have a different target in ICU.
       (
           (zone, target, icuLinks[zone])
           for (zone, target) in ianaLinks.items()
           if isICULink(zone) and target != icuLinks[zone]
       ),
       # IANA links which are zones in ICU.
       (
           (zone, target, zone.name)
           for (zone, target) in ianaLinks.items()
           if isICUZone(zone)
       ),
   )

   # Remove unnecessary UTC mappings.
   utcnames = ["Etc/UTC", "Etc/UCT", "Etc/GMT"]
   result = (
       (zone, target, icuTarget)
       for (zone, target, icuTarget) in result
       if target not in utcnames or icuTarget not in utcnames
   )

   return sorted(result, key=itemgetter(0))


def readZoneTab(tzdataDir):
   zone_country = dict()

   zonetab_path = tzdataDir.resolve("zone.tab")
   for line in tzdataDir.readlines(zonetab_path):
       if line.startswith("#"):
           continue
       (country, coords, zone, *comments) = line.strip().split("\t")
       assert zone not in zone_country
       zone_country[zone] = country

   return zone_country


# 6.5.1 AvailableNamedTimeZoneIdentifiers ( )
#
# https://tc39.es/ecma402/#sup-availablenamedtimezoneidentifiers
def availableNamedTimeZoneIdentifiers(tzdataDir, ignoreFactory):
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))

   with open(
       os.path.join(js_src_builtin_intl_dir, "TimeZoneMapping.yaml"),
       encoding="utf-8",
   ) as f:
       time_zone_mapping = yaml.safe_load(f)

   zone_country = readZoneTab(tzdataDir)

   def country_code_for(name):
       if name in zone_country:
           return zone_country[name]
       return time_zone_mapping[name]

   (ianaZones, ianaLinks) = readIANATimeZones(tzdataDir, ignoreFactory)

   (backzones, backlinks, packratlinks) = readIANAFiles(tzdataDir, ["backzone"])
   all_backzone_links = {**backlinks, **packratlinks}

   # Steps 1-3. (Not applicable)

   # Step 4.
   zones = set()
   links = dict()

   # Step 5. (Partial, only zones)
   for zone in ianaZones:
       # Step 5.a.
       primary = zone

       # Step 5.b. (Not applicable for zones)

       # Step 5.c.
       if primary.name in ["Etc/UTC", "Etc/GMT", "GMT"]:
           primary = Zone("UTC", primary.filename)

       # Step 5.d. (Not applicable)

       # Steps 5.e-f.
       if primary == zone:
           assert zone not in zones
           zones.add(primary)
       else:
           assert zone not in links
           links[zone] = primary.name

   # Step 5. (Partial, only links)
   for zone, target in ianaLinks.items():
       identifier = zone.name

       # Step 5.a.
       primary = identifier

       # Step 5.b.
       if identifier not in zone_country:
           # Step 5.b.i. (Not applicable)

           # Steps 5.b.ii-iii.
           if target.startswith("Etc/"):
               primary = target
           else:
               # Step 5.b.iii.1.
               identifier_code_code = country_code_for(identifier)

               # Step 5.b.iii.2.
               target_code_code = country_code_for(target)

               # Steps 5.b.iii.3-4
               if identifier_code_code == target_code_code:
                   primary = target
               else:
                   # Step 5.b.iii.4.a.
                   country_code_line_count = [
                       zone
                       for (zone, code) in zone_country.items()
                       if code == identifier_code_code
                   ]

                   # Steps 5.b.iii.4.b-c.
                   if len(country_code_line_count) == 1:
                       primary = country_code_line_count[0]
                   else:
                       assert Zone(identifier) in all_backzone_links
                       primary = all_backzone_links[Zone(identifier)]
                       assert identifier_code_code == country_code_for(primary)

       # Step 5.c.
       if primary in ["Etc/UTC", "Etc/GMT", "GMT"]:
           primary = "UTC"

       # Step 5.d. (Not applicable)

       # Steps 5.e-f.
       if primary == identifier:
           assert zone not in zones
           zones.add(zone)
       else:
           assert zone not in links
           links[zone] = primary

   # Ensure all zones and links are valid.
   validateTimeZones(zones, links)

   # Step 6.
   assert Zone("UTC") in zones

   # Step 7.
   return (zones, links)


generatedFileWarning = "// Generated by make_intl_data.py. DO NOT EDIT."
tzdataVersionComment = "// tzdata version = {0}"


def processTimeZones(tzdataDir, icuDir, icuTzDir, version, ignoreFactory, out):
   """Read the time zone info and create a new time zone cpp file."""
   print("Processing tzdata mapping...")
   (ianaZones, ianaLinks) = availableNamedTimeZoneIdentifiers(tzdataDir, ignoreFactory)
   (icuZones, icuLinks) = readICUTimeZones(icuDir, icuTzDir, ignoreFactory)
   (legacyZones, legacyLinks) = readICULegacyZones(icuDir)

   if ignoreFactory:
       legacyZones.add(Zone("Factory"))

   # Remove all legacy ICU time zones.
   icuZones = {zone for zone in icuZones if zone not in legacyZones}
   icuLinks = {
       zone: target for (zone, target) in icuLinks.items() if zone not in legacyLinks
   }

   incorrectZones = findIncorrectICUZones(ianaZones, ianaLinks, icuZones, icuLinks)
   if not incorrectZones:
       print("<<< No incorrect ICU time zones found, please update Intl.js! >>>")
       print("<<< Maybe https://ssl.icu-project.org/trac/ticket/12044 was fixed? >>>")

   incorrectLinks = findIncorrectICULinks(ianaZones, ianaLinks, icuZones, icuLinks)
   if not incorrectLinks:
       print("<<< No incorrect ICU time zone links found, please update Intl.js! >>>")
       print("<<< Maybe https://ssl.icu-project.org/trac/ticket/12044 was fixed? >>>")

   print("Writing Intl tzdata file...")
   with open(out, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println(generatedFileWarning)
       println(tzdataVersionComment.format(version))
       println("")

       println("#ifndef builtin_intl_TimeZoneDataGenerated_h")
       println("#define builtin_intl_TimeZoneDataGenerated_h")
       println("")

       println("namespace js {")
       println("namespace timezone {")
       println("")

       println("// Format:")
       println('// "ZoneName" // ICU-Name [time zone file]')
       println("const char* const ianaZonesTreatedAsLinksByICU[] = {")
       for zone, icuZone in incorrectZones:
           println('    "%s", // %s [%s]' % (zone, icuZone, zone.filename))
       println("};")
       println("")

       println("// Format:")
       println('// "LinkName", "Target" // ICU-Target [time zone file]')
       println("struct LinkAndTarget")
       println("{")
       println("    const char* const link;")
       println("    const char* const target;")
       println("};")
       println("")
       println("const LinkAndTarget ianaLinksCanonicalizedDifferentlyByICU[] = {")
       for zone, target, icuTarget in incorrectLinks:
           println(
               '    { "%s", "%s" }, // %s [%s]'
               % (zone, target, icuTarget, zone.filename)
           )
       println("};")
       println("")

       println(
           "// Legacy ICU time zones, these are not valid IANA time zone names. We also"
       )
       println("// disallow the old and deprecated System V time zones.")
       println(
           "// https://ssl.icu-project.org/repos/icu/trunk/icu4c/source/tools/tzcode/icuzones"
       )  # NOQA: E501
       println("const char* const legacyICUTimeZones[] = {")
       for zone in chain(sorted(legacyLinks.keys()), sorted(legacyZones)):
           println('    "%s",' % zone)
       println("};")
       println("")

       println("} // namespace timezone")
       println("} // namespace js")
       println("")
       println("#endif /* builtin_intl_TimeZoneDataGenerated_h */")


def generateTzDataTestLinks(tzdataDir, version, ignoreFactory, testDir):
   fileName = "timeZone_links.js"

   # Read zone and link infos.
   (_, links) = availableNamedTimeZoneIdentifiers(tzdataDir, ignoreFactory)

   with open(
       os.path.join(testDir, fileName), mode="w", encoding="utf-8", newline=""
   ) as f:
       println = partial(print, file=f)

       println('// |reftest| skip-if(!this.hasOwnProperty("Intl"))')
       println("")
       println(generatedFileWarning)
       println(tzdataVersionComment.format(version))
       println(
           """
const tzMapper = [
   x => x,
   x => x.toUpperCase(),
   x => x.toLowerCase(),
];
"""
       )

       println("// Link names derived from IANA Time Zone Database.")
       println("const links = {")
       for zone, target in sorted(links.items(), key=itemgetter(0)):
           println('    "%s": "%s",' % (zone, target))
       println("};")

       println(
           """
for (let [linkName, target] of Object.entries(links)) {
   if (target === "Etc/UTC" || target === "Etc/GMT")
       target = "UTC";

   for (let map of tzMapper) {
       let dtf = new Intl.DateTimeFormat(undefined, {timeZone: map(linkName)});
       let resolvedTimeZone = dtf.resolvedOptions().timeZone;
       assertEq(resolvedTimeZone, target, `${linkName} -> ${target}`);
   }
}
"""
       )
       println(
           """
if (typeof reportCompare === "function")
   reportCompare(0, 0, "ok");
"""
       )


def generateTzDataTestVersion(tzdataDir, version, testDir):
   fileName = "timeZone_version.js"

   with open(
       os.path.join(testDir, fileName), mode="w", encoding="utf-8", newline=""
   ) as f:
       println = partial(print, file=f)

       println('// |reftest| skip-if(!this.hasOwnProperty("Intl"))')
       println("")
       println(generatedFileWarning)
       println(tzdataVersionComment.format(version))
       println(f"""const tzdata = "{version}";""")

       println(
           """
if (typeof getICUOptions === "undefined") {
   var getICUOptions = SpecialPowers.Cu.getJSTestingFunctions().getICUOptions;
}

var options = getICUOptions();

assertEq(options.tzdata, tzdata);

if (typeof reportCompare === "function")
   reportCompare(0, 0, "ok");
"""
       )


def generateTzDataTestCanonicalZones(tzdataDir, version, ignoreFactory, testDir):
   fileName = "supportedValuesOf-timeZones-canonical.js"

   # Read zone and link infos.
   (zones, _) = availableNamedTimeZoneIdentifiers(tzdataDir, ignoreFactory)

   with open(
       os.path.join(testDir, fileName), mode="w", encoding="utf-8", newline=""
   ) as f:
       println = partial(print, file=f)

       println('// |reftest| skip-if(!this.hasOwnProperty("Intl"))')
       println("")
       println(generatedFileWarning)
       println(tzdataVersionComment.format(version))

       println("const zones = [")
       for zone in sorted(zones):
           println(f'  "{zone}",')
       println("];")

       println(
           """
let supported = Intl.supportedValuesOf("timeZone");

assertEqArray(supported, zones);

if (typeof reportCompare === "function")
   reportCompare(0, 0, "ok");
"""
       )


def generateTzDataTestZones(tzdataDir, version, ignoreFactory, testDir):
   fileName = "zones-and-links.js"

   # Read zone and link infos.
   (zones, links) = availableNamedTimeZoneIdentifiers(tzdataDir, ignoreFactory)

   with open(
       os.path.join(testDir, fileName), mode="w", encoding="utf-8", newline=""
   ) as f:
       println = partial(print, file=f)

       println('// |reftest| skip-if(!this.hasOwnProperty("Temporal"))')
       println("")
       println(generatedFileWarning)
       println(tzdataVersionComment.format(version))

       println("const zones = [")
       for zone in sorted(zones):
           println(f'  "{zone}",')
       println("];")

       println("const links = {")
       for link, target in sorted(links.items(), key=itemgetter(0)):
           println(f'  "{link}": "{target}",')
       println("};")

       println(
           """
let epochNanoseconds = [
 new Temporal.PlainDate(1900, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(1950, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(1960, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(1970, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(1980, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(1990, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(2000, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(2010, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(2020, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
 new Temporal.PlainDate(2030, 1, 1).toZonedDateTime("UTC").epochNanoseconds,
];

function timeZoneId(zdt) {
 let str = zdt.toString();
 let m = str.match(/(?<=\\[)[\\w\\/_+-]+(?=\\])/);
 assertEq(m !== null, true, str);
 return m[0];
}

for (let zone of zones) {
 let zdt = new Temporal.ZonedDateTime(0n, zone);

 assertEq(zdt.timeZoneId, zone);
 assertEq(timeZoneId(zdt), zone);
}

for (let [link, zone] of Object.entries(links)) {
 assertEq(link === zone, false, `link=${link}, zone=${zone}`);
 assertEq(zones.includes(zone), true, `zone=${zone}`);

 let zdtLink = new Temporal.ZonedDateTime(0n, link);
 let zdtZone = new Temporal.ZonedDateTime(0n, zone);

 assertEq(zdtLink.timeZoneId, link);
 assertEq(timeZoneId(zdtLink), link);

 assertEq(zdtZone.timeZoneId, zone);
 assertEq(timeZoneId(zdtZone), zone);

 assertEq(zdtLink.equals(zdtZone), true, `link=${link}, zone=${zone}`);

 assertEq(
   zdtLink.offsetNanoseconds,
   zdtZone.offsetNanoseconds,
   `link=${link}, zone=${zone}`
 );

 for (let epochNs of epochNanoseconds) {
   assertEq(
     new Temporal.ZonedDateTime(epochNs, link).offsetNanoseconds,
     new Temporal.ZonedDateTime(epochNs, zone).offsetNanoseconds,
     `link=${link}, zone=${zone}, epochNs=${epochNs}`
   );
 }
}

if (typeof reportCompare === "function")
 reportCompare(0, 0, "ok");
"""
       )


def generateTzDataTests(tzdataDir, version, ignoreFactory, testDir):
   dtfTestDir = os.path.join(testDir, "DateTimeFormat")
   if not os.path.isdir(dtfTestDir):
       raise RuntimeError("not a directory: %s" % dtfTestDir)

   zdtTestDir = os.path.join(testDir, "../Temporal/ZonedDateTime")
   if not os.path.isdir(zdtTestDir):
       raise RuntimeError("not a directory: %s" % zdtTestDir)

   generateTzDataTestLinks(tzdataDir, version, ignoreFactory, dtfTestDir)
   generateTzDataTestVersion(tzdataDir, version, dtfTestDir)
   generateTzDataTestCanonicalZones(tzdataDir, version, ignoreFactory, testDir)
   generateTzDataTestZones(tzdataDir, version, ignoreFactory, zdtTestDir)


def updateTzdata(topsrcdir, args):
   """Update the time zone cpp file."""

   icuDir = os.path.join(topsrcdir, "intl/icu/source")
   if not os.path.isdir(icuDir):
       raise RuntimeError("not a directory: %s" % icuDir)

   icuTzDir = os.path.join(topsrcdir, "intl/tzdata/source")
   if not os.path.isdir(icuTzDir):
       raise RuntimeError("not a directory: %s" % icuTzDir)

   intlTestDir = os.path.join(topsrcdir, "js/src/tests/non262/Intl")
   if not os.path.isdir(intlTestDir):
       raise RuntimeError("not a directory: %s" % intlTestDir)

   tzDir = args.tz
   if tzDir is not None and not (os.path.isdir(tzDir) or os.path.isfile(tzDir)):
       raise RuntimeError("not a directory or file: %s" % tzDir)
   out = args.out

   # Ignore the placeholder time zone "Factory".
   ignoreFactory = True

   version = icuTzDataVersion(icuTzDir)
   url = (
       "https://www.iana.org/time-zones/repository/releases/tzdata%s.tar.gz" % version
   )

   print("Arguments:")
   print("\ttzdata version: %s" % version)
   print("\ttzdata URL: %s" % url)
   print("\ttzdata directory|file: %s" % tzDir)
   print("\tICU directory: %s" % icuDir)
   print("\tICU timezone directory: %s" % icuTzDir)
   print("\tOutput file: %s" % out)
   print("")

   def updateFrom(f):
       if os.path.isfile(f) and tarfile.is_tarfile(f):
           with tarfile.open(f, "r:*") as tar:
               processTimeZones(
                   TzDataFile(tar),
                   icuDir,
                   icuTzDir,
                   version,
                   ignoreFactory,
                   out,
               )
               generateTzDataTests(
                   TzDataFile(tar), version, ignoreFactory, intlTestDir
               )
       elif os.path.isdir(f):
           processTimeZones(
               TzDataDir(f),
               icuDir,
               icuTzDir,
               version,
               ignoreFactory,
               out,
           )
           generateTzDataTests(TzDataDir(f), version, ignoreFactory, intlTestDir)
       else:
           raise RuntimeError("unknown format")

   if tzDir is None:
       print("Downloading tzdata file...")
       with closing(urlopen(url)) as tzfile:
           fname = urlsplit(tzfile.geturl()).path.split("/")[-1]
           with tempfile.NamedTemporaryFile(suffix=fname) as tztmpfile:
               print("File stored in %s" % tztmpfile.name)
               tztmpfile.write(tzfile.read())
               tztmpfile.flush()
               updateFrom(tztmpfile.name)
   else:
       updateFrom(tzDir)


def readCurrencyFile(tree):
   reCurrency = re.compile(r"^[A-Z]{3}$")
   reIntMinorUnits = re.compile(r"^\d+$")

   for country in tree.iterfind(".//CcyNtry"):
       # Skip entry if no currency information is available.
       currency = country.findtext("Ccy")
       if currency is None:
           continue
       assert reCurrency.match(currency)

       minorUnits = country.findtext("CcyMnrUnts")
       assert minorUnits is not None

       # Skip all entries without minorUnits or which use the default minorUnits.
       if reIntMinorUnits.match(minorUnits) and int(minorUnits) != 2:
           currencyName = country.findtext("CcyNm")
           countryName = country.findtext("CtryNm")
           yield (currency, int(minorUnits), currencyName, countryName)


def writeCurrencyFile(published, currencies, out):
   with open(out, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println(generatedFileWarning)
       println(f"// Version: {published}")

       println(
           """
/**
* Mapping from currency codes to the number of decimal digits used for them.
* Default is 2 digits.
*
* Spec: ISO 4217 Currency and Funds Code List.
* http://www.currency-iso.org/en/home/tables/table-a1.html
*/"""
       )
       println("var currencyDigits = {")
       for currency, entries in groupby(
           sorted(currencies, key=itemgetter(0)), itemgetter(0)
       ):
           for _, minorUnits, currencyName, countryName in entries:
               println(f"  // {currencyName} ({countryName})")
           println(f"  {currency}: {minorUnits},")
       println("};")


def updateCurrency(topsrcdir, args):
   """Update the CurrencyDataGenerated.js file."""
   import xml.etree.ElementTree as ET
   from random import randint

   url = args.url
   out = args.out
   filename = args.file

   print("Arguments:")
   print("\tDownload url: %s" % url)
   print("\tLocal currency file: %s" % filename)
   print("\tOutput file: %s" % out)
   print("")

   def updateFrom(currencyFile):
       print("Processing currency code list file...")
       tree = ET.parse(currencyFile)
       published = tree.getroot().attrib["Pblshd"]
       currencies = readCurrencyFile(tree)

       print("Writing CurrencyData file...")
       writeCurrencyFile(published, currencies, out)

   if filename is not None:
       print("Always make sure you have the newest currency code list file!")
       updateFrom(filename)
   else:
       print("Downloading currency & funds code list...")
       request = UrlRequest(url)
       request.add_header(
           "User-agent",
           "Mozilla/5.0 (Mobile; rv:{0}.0) Gecko/{0}.0 Firefox/{0}.0".format(
               randint(1, 999)
           ),
       )
       with closing(urlopen(request)) as currencyFile:
           fname = urlsplit(currencyFile.geturl()).path.split("/")[-1]
           with tempfile.NamedTemporaryFile(suffix=fname) as currencyTmpFile:
               print("File stored in %s" % currencyTmpFile.name)
               currencyTmpFile.write(currencyFile.read())
               currencyTmpFile.flush()
               updateFrom(currencyTmpFile.name)


def writeUnicodeExtensionsMappings(println, mapping, extension):
   println(
       f"""
template <size_t Length>
static inline bool Is{extension}Key(mozilla::Span<const char> key, const char (&str)[Length]) {{
 static_assert(Length == {extension}KeyLength + 1,
               "{extension} extension key is two characters long");
 return memcmp(key.data(), str, Length - 1) == 0;
}}

template <size_t Length>
static inline bool Is{extension}Type(mozilla::Span<const char> type, const char (&str)[Length]) {{
 static_assert(Length > {extension}KeyLength + 1,
               "{extension} extension type contains more than two characters");
 return type.size() == (Length - 1) &&
        memcmp(type.data(), str, Length - 1) == 0;
}}
""".rstrip("\n")
   )

   linear_search_max_length = 4

   needs_binary_search = any(
       len(replacements.items()) > linear_search_max_length
       for replacements in mapping.values()
   )

   if needs_binary_search:
       println(
           f"""
static int32_t Compare{extension}Type(const char* a, mozilla::Span<const char> b) {{
 MOZ_ASSERT(!std::char_traits<char>::find(b.data(), b.size(), '\\0'),
            "unexpected null-character in string");

 using UnsignedChar = unsigned char;
 for (size_t i = 0; i < b.size(); i++) {{
   // |a| is zero-terminated and |b| doesn't contain a null-terminator. So if
   // we've reached the end of |a|, the below if-statement will always be true.
   // That ensures we don't read past the end of |a|.
   if (int32_t r = UnsignedChar(a[i]) - UnsignedChar(b[i])) {{
     return r;
   }}
 }}

 // Return zero if both strings are equal or a positive number if |b| is a
 // prefix of |a|.
 return int32_t(UnsignedChar(a[b.size()]));
}}

template <size_t Length>
static inline const char* Search{extension}Replacement(
 const char* (&types)[Length], const char* (&aliases)[Length],
 mozilla::Span<const char> type) {{

 auto p = std::lower_bound(std::begin(types), std::end(types), type,
                           [](const auto& a, const auto& b) {{
                             return Compare{extension}Type(a, b) < 0;
                           }});
 if (p != std::end(types) && Compare{extension}Type(*p, type) == 0) {{
   return aliases[std::distance(std::begin(types), p)];
 }}
 return nullptr;
}}
""".rstrip("\n")
       )

   println(
       f"""
/**
* Mapping from deprecated BCP 47 {extension} extension types to their preferred
* values.
*
* Spec: https://www.unicode.org/reports/tr35/#Unicode_Locale_Extension_Data_Files
* Spec: https://www.unicode.org/reports/tr35/#t_Extension
*/
const char* mozilla::intl::Locale::Replace{extension}ExtensionType(
   mozilla::Span<const char> key, mozilla::Span<const char> type) {{
 MOZ_ASSERT(key.size() == {extension}KeyLength);
 MOZ_ASSERT(IsCanonicallyCased{extension}Key(key));

 MOZ_ASSERT(type.size() > {extension}KeyLength);
 MOZ_ASSERT(IsCanonicallyCased{extension}Type(type));
"""
   )

   def to_hash_key(replacements):
       return str(sorted(replacements.items()))

   def write_array(subtags, name, length):
       max_entries = (80 - len("    ")) // (length + len('"", '))

       println(f"    static const char* {name}[{len(subtags)}] = {{")

       for entries in grouper(subtags, max_entries):
           entries = (
               f'"{tag}"'.center(length + 2) for tag in entries if tag is not None
           )
           println("        {},".format(", ".join(entries)))

       println("    };")

   # Merge duplicate keys.
   key_aliases = {}
   for key, replacements in sorted(mapping.items(), key=itemgetter(0)):
       hash_key = to_hash_key(replacements)
       if hash_key not in key_aliases:
           key_aliases[hash_key] = []
       else:
           key_aliases[hash_key].append(key)

   first_key = True
   for key, replacements in sorted(mapping.items(), key=itemgetter(0)):
       hash_key = to_hash_key(replacements)
       if key in key_aliases[hash_key]:
           continue

       cond = (f'Is{extension}Key(key, "{k}")' for k in [key] + key_aliases[hash_key])

       if_kind = "if" if first_key else "else if"
       cond = (" ||\n" + " " * (2 + len(if_kind) + 2)).join(cond)
       println(
           f"""
 {if_kind} ({cond}) {{""".strip("\n")
       )
       first_key = False

       replacements = sorted(replacements.items(), key=itemgetter(0))

       if len(replacements) > linear_search_max_length:
           types = [t for (t, _) in replacements]
           preferred = [r for (_, r) in replacements]
           max_len = max(len(k) for k in types + preferred)

           write_array(types, "types", max_len)
           write_array(preferred, "aliases", max_len)
           println(
               f"""
   return Search{extension}Replacement(types, aliases, type);
""".strip("\n")
           )
       else:
           for type, replacement in replacements:
               println(
                   f"""
   if (Is{extension}Type(type, "{type}")) {{
     return "{replacement}";
   }}""".strip("\n")
               )

       println(
           """
 }""".lstrip("\n")
       )

   println(
       """
 return nullptr;
}
""".strip("\n")
   )


def readICUUnitResourceFile(filepath):
   """Return a set of unit descriptor pairs where the first entry denotes the unit type and the
   second entry the unit name.

   Example:

   root{
       units{
           compound{
           }
           coordinate{
           }
           length{
               meter{
               }
           }
       }
       unitsNarrow:alias{"/LOCALE/unitsShort"}
       unitsShort{
           duration{
               day{
               }
               day-person:alias{"/LOCALE/unitsShort/duration/day"}
           }
           length{
               meter{
               }
           }
       }
   }

   Returns {("length", "meter"), ("duration", "day"), ("duration", "day-person")}
   """

   start_table_re = re.compile(r"^([\w\-%:\"]+)\{$")
   end_table_re = re.compile(r"^\}$")
   table_entry_re = re.compile(r"^([\w\-%:\"]+)\{\"(.*?)\"\}$")

   # The current resource table.
   table = {}

   # List of parent tables when parsing.
   parents = []

   # Track multi-line comments state.
   in_multiline_comment = False

   for line in flines(filepath, "utf-8-sig"):
       # Remove leading and trailing whitespace.
       line = line.strip()

       # Skip over comments.
       if in_multiline_comment:
           if line.endswith("*/"):
               in_multiline_comment = False
           continue

       if line.startswith("//"):
           continue

       if line.startswith("/*"):
           in_multiline_comment = True
           continue

       # Try to match the start of a table, e.g. `length{` or `meter{`.
       match = start_table_re.match(line)
       if match:
           parents.append(table)
           table_name = match.group(1)
           new_table = {}
           table[table_name] = new_table
           table = new_table
           continue

       # Try to match the end of a table.
       match = end_table_re.match(line)
       if match:
           table = parents.pop()
           continue

       # Try to match a table entry, e.g. `dnam{"meter"}`.
       match = table_entry_re.match(line)
       if match:
           entry_key = match.group(1)
           entry_value = match.group(2)
           table[entry_key] = entry_value
           continue

       raise Exception(f"unexpected line: '{line}' in {filepath}")

   assert len(parents) == 0, "Not all tables closed"
   assert len(table) == 1, "More than one root table"

   # Remove the top-level language identifier table.
   (_, unit_table) = table.popitem()

   # Add all units for the three display formats "units", "unitsNarrow", and "unitsShort".
   # But exclude the pseudo-units "compound" and "ccoordinate".
   return {
       (unit_type, unit_name if not unit_name.endswith(":alias") else unit_name[:-6])
       for unit_display in ("units", "unitsNarrow", "unitsShort")
       if unit_display in unit_table
       for (unit_type, unit_names) in unit_table[unit_display].items()
       if unit_type not in {"compound", "coordinate"}
       for unit_name in unit_names.keys()
   }


def computeSupportedUnits(all_units, sanctioned_units):
   """Given the set of all possible ICU unit identifiers and the set of sanctioned unit
   identifiers, compute the set of effectively supported ICU unit identifiers.
   """

   def find_match(unit):
       unit_match = [
           (unit_type, unit_name)
           for (unit_type, unit_name) in all_units
           if unit_name == unit
       ]
       if unit_match:
           assert len(unit_match) == 1
           return unit_match[0]
       return None

   def compound_unit_identifiers():
       for numerator in sanctioned_units:
           for denominator in sanctioned_units:
               yield f"{numerator}-per-{denominator}"

   supported_simple_units = {find_match(unit) for unit in sanctioned_units}
   assert None not in supported_simple_units

   supported_compound_units = {
       unit_match
       for unit_match in (find_match(unit) for unit in compound_unit_identifiers())
       if unit_match
   }

   return supported_simple_units | supported_compound_units


def readICUDataFilterForUnits(data_filter_file):
   with open(data_filter_file, encoding="utf-8") as f:
       data_filter = json.load(f)

   # Find the rule set for the "unit_tree".
   unit_tree_rules = [
       entry["rules"]
       for entry in data_filter["resourceFilters"]
       if entry["categories"] == ["unit_tree"]
   ]
   assert len(unit_tree_rules) == 1

   # Compute the list of included units from that rule set. The regular expression must match
   # "+/*/length/meter" and mustn't match either "-/*" or "+/*/compound".
   included_unit_re = re.compile(r"^\+/\*/(.+?)/(.+)$")
   filtered_units = (included_unit_re.match(unit) for unit in unit_tree_rules[0])

   return {(unit.group(1), unit.group(2)) for unit in filtered_units if unit}


def writeSanctionedSimpleUnitIdentifiersFiles(all_units, sanctioned_units):
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   intl_components_src_dir = os.path.join(
       js_src_builtin_intl_dir, "../../../../intl/components/src"
   )

   def find_unit_type(unit):
       result = [
           unit_type for (unit_type, unit_name) in all_units if unit_name == unit
       ]
       assert result and len(result) == 1
       return result[0]

   sanctioned_js_file = os.path.join(
       js_src_builtin_intl_dir, "SanctionedSimpleUnitIdentifiersGenerated.js"
   )
   with open(sanctioned_js_file, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       sanctioned_units_object = json.dumps(
           {unit: True for unit in sorted(sanctioned_units)},
           sort_keys=True,
           indent=2,
           separators=(",", ": "),
       )

       println(generatedFileWarning)

       println(
           """
/**
* The list of currently supported simple unit identifiers.
*
* Intl.NumberFormat Unified API Proposal
*/"""
       )

       println("// prettier-ignore")
       println(f"var sanctionedSimpleUnitIdentifiers = {sanctioned_units_object};")

   sanctioned_h_file = os.path.join(intl_components_src_dir, "MeasureUnitGenerated.h")
   with open(sanctioned_h_file, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println(generatedFileWarning)

       println(
           """
#ifndef intl_components_MeasureUnitGenerated_h
#define intl_components_MeasureUnitGenerated_h

namespace mozilla::intl {

struct SimpleMeasureUnit {
 const char* const type;
 const char* const name;
};

/**
* The list of currently supported simple unit identifiers.
*
* The list must be kept in alphabetical order of |name|.
*/
inline constexpr SimpleMeasureUnit simpleMeasureUnits[] = {
   // clang-format off"""
       )

       for unit_name in sorted(sanctioned_units):
           println(f'  {{"{find_unit_type(unit_name)}", "{unit_name}"}},')

       println(
           """
   // clang-format on
};

}  // namespace mozilla::intl

#endif
""".strip("\n")
       )

   writeUnitTestFiles(all_units, sanctioned_units)


def writeUnitTestFiles(all_units, sanctioned_units):
   """Generate test files for unit number formatters."""

   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   test_dir = os.path.join(
       js_src_builtin_intl_dir, "../../tests/non262/Intl/NumberFormat"
   )

   def write_test(file_name, test_content, indent=4):
       file_path = os.path.join(test_dir, file_name)
       with open(file_path, mode="w", encoding="utf-8", newline="") as f:
           println = partial(print, file=f)

           println('// |reftest| skip-if(!this.hasOwnProperty("Intl"))')
           println("")
           println(generatedFileWarning)
           println("")

           sanctioned_units_array = json.dumps(
               [unit for unit in sorted(sanctioned_units)],
               indent=indent,
               separators=(",", ": "),
           )

           println(
               f"const sanctionedSimpleUnitIdentifiers = {sanctioned_units_array};"
           )

           println(test_content)

           println(
               """
if (typeof reportCompare === "function")
{}reportCompare(true, true);""".format(" " * indent)
           )

   write_test(
       "unit-compound-combinations.js",
       """
// Test all simple unit identifier combinations are allowed.

for (const numerator of sanctionedSimpleUnitIdentifiers) {
   for (const denominator of sanctionedSimpleUnitIdentifiers) {
       const unit = `${numerator}-per-${denominator}`;
       const nf = new Intl.NumberFormat("en", {style: "unit", unit});

       assertEq(nf.format(1), nf.formatToParts(1).map(p => p.value).join(""));
   }
}""",
   )

   all_units_array = json.dumps(
       ["-".join(unit) for unit in sorted(all_units)], indent=4, separators=(",", ": ")
   )

   write_test(
       "unit-well-formed.js",
       f"""
const allUnits = {all_units_array};
"""
       + r"""
// Test only sanctioned unit identifiers are allowed.

for (const typeAndUnit of allUnits) {
   const [_, type, unit] = typeAndUnit.match(/(\w+)-(.+)/);

   let allowed;
   if (unit.includes("-per-")) {
       const [numerator, denominator] = unit.split("-per-");
       allowed = sanctionedSimpleUnitIdentifiers.includes(numerator) &&
                 sanctionedSimpleUnitIdentifiers.includes(denominator);
   } else {
       allowed = sanctionedSimpleUnitIdentifiers.includes(unit);
   }

   if (allowed) {
       const nf = new Intl.NumberFormat("en", {style: "unit", unit});
       assertEq(nf.format(1), nf.formatToParts(1).map(p => p.value).join(""));
   } else {
       assertThrowsInstanceOf(() => new Intl.NumberFormat("en", {style: "unit", unit}),
                              RangeError, `Missing error for "${typeAndUnit}"`);
   }
}""",
   )

   write_test(
       "unit-formatToParts-has-unit-field.js",
       """
// Test only English and Chinese to keep the overall runtime reasonable.
//
// Chinese is included because it contains more than one "unit" element for
// certain unit combinations.
const locales = ["en", "zh"];

// Plural rules for English only differentiate between "one" and "other". Plural
// rules for Chinese only use "other". That means we only need to test two values
// per unit.
const values = [0, 1];

// Ensure unit formatters contain at least one "unit" element.

for (const locale of locales) {
 for (const unit of sanctionedSimpleUnitIdentifiers) {
   const nf = new Intl.NumberFormat(locale, {style: "unit", unit});

   for (const value of values) {
     assertEq(nf.formatToParts(value).some(e => e.type === "unit"), true,
              `locale=${locale}, unit=${unit}`);
   }
 }

 for (const numerator of sanctionedSimpleUnitIdentifiers) {
   for (const denominator of sanctionedSimpleUnitIdentifiers) {
     const unit = `${numerator}-per-${denominator}`;
     const nf = new Intl.NumberFormat(locale, {style: "unit", unit});

     for (const value of values) {
       assertEq(nf.formatToParts(value).some(e => e.type === "unit"), true,
                `locale=${locale}, unit=${unit}`);
     }
   }
 }
}""",
       indent=2,
   )


def updateUnits(topsrcdir, args):
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   icu_path = os.path.join(topsrcdir, "intl", "icu")
   icu_unit_path = os.path.join(icu_path, "source", "data", "unit")

   with open(
       os.path.join(js_src_builtin_intl_dir, "SanctionedSimpleUnitIdentifiers.yaml"),
       encoding="utf-8",
   ) as f:
       sanctioned_units = yaml.safe_load(f)

   # Read all possible ICU unit identifiers from the "unit/root.txt" resource.
   unit_root_file = os.path.join(icu_unit_path, "root.txt")
   all_units = readICUUnitResourceFile(unit_root_file)

   # Compute the set of effectively supported ICU unit identifiers.
   supported_units = computeSupportedUnits(all_units, sanctioned_units)

   # Read the list of units we're including into the ICU data file.
   data_filter_file = os.path.join(icu_path, "data_filter.json")
   filtered_units = readICUDataFilterForUnits(data_filter_file)

   # Both sets must match to avoid resource loading errors at runtime.
   if supported_units != filtered_units:

       def units_to_string(units):
           return ", ".join("/".join(u) for u in units)

       missing = supported_units - filtered_units
       if missing:
           raise RuntimeError(f"Missing units: {units_to_string(missing)}")

       # Not exactly an error, but we currently don't have a use case where we need to support
       # more units than required by ECMA-402.
       extra = filtered_units - supported_units
       if extra:
           raise RuntimeError(f"Unnecessary units: {units_to_string(extra)}")

   writeSanctionedSimpleUnitIdentifiersFiles(all_units, sanctioned_units)


def readICUNumberingSystemsResourceFile(filepath):
   """Returns a dictionary of numbering systems where the key denotes the numbering system name
   and the value a dictionary with additional numbering system data.

   Example:

   numberingSystems:table(nofallback){
       numberingSystems{
           latn{
               algorithmic:int{0}
               desc{"0123456789"}
               radix:int{10}
           }
           roman{
               algorithmic:int{1}
               desc{"%roman-upper"}
               radix:int{10}
           }
       }
   }

   Returns {"latn": {"digits": "0123456789", "algorithmic": False},
            "roman": {"algorithmic": True}}
   """

   start_table_re = re.compile(r"^(\w+)(?:\:[\w\(\)]+)?\{$")
   end_table_re = re.compile(r"^\}$")
   table_entry_re = re.compile(r"^(\w+)(?:\:[\w\(\)]+)?\{(?:(?:\"(.*?)\")|(\d+))\}$")

   # The current resource table.
   table = {}

   # List of parent tables when parsing.
   parents = []

   # Track multi-line comments state.
   in_multiline_comment = False

   for line in flines(filepath, "utf-8-sig"):
       # Remove leading and trailing whitespace.
       line = line.strip()

       # Skip over comments.
       if in_multiline_comment:
           if line.endswith("*/"):
               in_multiline_comment = False
           continue

       if line.startswith("//"):
           continue

       if line.startswith("/*"):
           in_multiline_comment = True
           continue

       # Try to match the start of a table, e.g. `latn{`.
       match = start_table_re.match(line)
       if match:
           parents.append(table)
           table_name = match.group(1)
           new_table = {}
           table[table_name] = new_table
           table = new_table
           continue

       # Try to match the end of a table.
       match = end_table_re.match(line)
       if match:
           table = parents.pop()
           continue

       # Try to match a table entry, e.g. `desc{"0123456789"}`.
       match = table_entry_re.match(line)
       if match:
           entry_key = match.group(1)
           entry_value = (
               match.group(2) if match.group(2) is not None else int(match.group(3))
           )
           table[entry_key] = entry_value
           continue

       raise Exception(f"unexpected line: '{line}' in {filepath}")

   assert len(parents) == 0, "Not all tables closed"
   assert len(table) == 1, "More than one root table"

   # Remove the two top-level "numberingSystems" tables.
   (_, numbering_systems) = table.popitem()
   (_, numbering_systems) = numbering_systems.popitem()

   # Assert all numbering systems use base 10.
   assert all(ns["radix"] == 10 for ns in numbering_systems.values())

   # Return the numbering systems.
   return {
       key: (
           {"digits": value["desc"], "algorithmic": False}
           if not bool(value["algorithmic"])
           else {"algorithmic": True}
       )
       for (key, value) in numbering_systems.items()
   }


def writeNumberingSystemFiles(numbering_systems):
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))

   numbering_systems_js_file = os.path.join(
       js_src_builtin_intl_dir, "NumberingSystemsGenerated.h"
   )
   with open(numbering_systems_js_file, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println(generatedFileWarning)

       println(
           """
/**
* The list of numbering systems with simple digit mappings.
*/

#ifndef builtin_intl_NumberingSystemsGenerated_h
#define builtin_intl_NumberingSystemsGenerated_h
"""
       )

       simple_numbering_systems = sorted(
           name
           for (name, value) in numbering_systems.items()
           if not value["algorithmic"]
       )

       println("// clang-format off")
       println("#define NUMBERING_SYSTEMS_WITH_SIMPLE_DIGIT_MAPPINGS \\")
       println(
           "{}".format(
               ", \\\n".join(f'  "{name}"' for name in simple_numbering_systems)
           )
       )
       println("// clang-format on")
       println("")

       println("#endif  // builtin_intl_NumberingSystemsGenerated_h")

   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   test_dir = os.path.join(js_src_builtin_intl_dir, "../../tests/non262/Intl")

   intl_shell_js_file = os.path.join(test_dir, "shell.js")

   with open(intl_shell_js_file, mode="w", encoding="utf-8", newline="") as f:
       println = partial(print, file=f)

       println(generatedFileWarning)

       println(
           f"""
// source: CLDR file common/bcp47/number.xml; version CLDR {readCLDRVersionFromICU()}.
// https://github.com/unicode-org/cldr/blob/master/common/bcp47/number.xml
// https://github.com/unicode-org/cldr/blob/master/common/supplemental/numberingSystems.xml
""".rstrip()
       )

       numbering_systems_object = json.dumps(
           numbering_systems,
           indent=2,
           separators=(",", ": "),
           sort_keys=True,
           ensure_ascii=False,
       )
       println(f"const numberingSystems = {numbering_systems_object};")


def updateNumberingSystems(topsrcdir, args):
   js_src_builtin_intl_dir = os.path.dirname(os.path.abspath(__file__))
   icu_path = os.path.join(topsrcdir, "intl", "icu")
   icu_misc_path = os.path.join(icu_path, "source", "data", "misc")

   with open(
       os.path.join(js_src_builtin_intl_dir, "NumberingSystems.yaml"),
       encoding="utf-8",
   ) as f:
       numbering_systems = yaml.safe_load(f)

   # Read all possible ICU unit identifiers from the "misc/numberingSystems.txt" resource.
   misc_ns_file = os.path.join(icu_misc_path, "numberingSystems.txt")
   all_numbering_systems = readICUNumberingSystemsResourceFile(misc_ns_file)

   all_numbering_systems_simple_digits = {
       name
       for (name, value) in all_numbering_systems.items()
       if not value["algorithmic"]
   }

   # Assert ICU includes support for all required numbering systems. If this assertion fails,
   # something is broken in ICU.
   assert all_numbering_systems_simple_digits.issuperset(numbering_systems), (
       f"{numbering_systems.difference(all_numbering_systems_simple_digits)}"
   )

   # Assert the spec requires support for all numbering systems with simple digit mappings. If
   # this assertion fails, file a PR at <https://github.com/tc39/ecma402> to include any new
   # numbering systems.
   assert all_numbering_systems_simple_digits.issubset(numbering_systems), (
       f"{all_numbering_systems_simple_digits.difference(numbering_systems)}"
   )

   writeNumberingSystemFiles(all_numbering_systems)


if __name__ == "__main__":
   import argparse

   # This script must reside in js/src/builtin/intl to work correctly.
   (thisDir, thisFile) = os.path.split(os.path.abspath(__file__))
   dirPaths = os.path.normpath(thisDir).split(os.sep)
   if "/".join(dirPaths[-4:]) != "js/src/builtin/intl":
       raise RuntimeError("%s must reside in js/src/builtin/intl" % __file__)
   topsrcdir = "/".join(dirPaths[:-4])

   def EnsureHttps(v):
       if not v.startswith("https:"):
           raise argparse.ArgumentTypeError("URL protocol must be https: " % v)
       return v

   parser = argparse.ArgumentParser(description="Update intl data.")
   subparsers = parser.add_subparsers(help="Select update mode")

   parser_cldr_tags = subparsers.add_parser(
       "langtags", help="Update CLDR language tags data"
   )
   parser_cldr_tags.add_argument(
       "--version", metavar="VERSION", help="CLDR version number"
   )
   parser_cldr_tags.add_argument(
       "--url",
       metavar="URL",
       default="https://unicode.org/Public/cldr/<VERSION>/cldr-common-<VERSION>.zip",
       type=EnsureHttps,
       help="Download url CLDR data (default: %(default)s)",
   )
   parser_cldr_tags.add_argument(
       "--out",
       default=os.path.join(
           topsrcdir, "intl", "components", "src", "LocaleGenerated.cpp"
       ),
       help="Output file (default: %(default)s)",
   )
   parser_cldr_tags.add_argument(
       "file", nargs="?", help="Local cldr-common.zip file, if omitted uses <URL>"
   )
   parser_cldr_tags.set_defaults(func=updateCLDRLangTags)

   parser_tz = subparsers.add_parser("tzdata", help="Update tzdata")
   parser_tz.add_argument(
       "--tz",
       help="Local tzdata directory or file, if omitted downloads tzdata "
       "distribution from https://www.iana.org/time-zones/",
   )
   parser_tz.add_argument(
       "--out",
       default=os.path.join(thisDir, "TimeZoneDataGenerated.h"),
       help="Output file (default: %(default)s)",
   )
   parser_tz.set_defaults(func=partial(updateTzdata, topsrcdir))

   parser_currency = subparsers.add_parser(
       "currency", help="Update currency digits mapping"
   )
   parser_currency.add_argument(
       "--url",
       metavar="URL",
       default="https://www.six-group.com/dam/download/financial-information/data-center/iso-currrency/lists/list-one.xml",  # NOQA: E501
       type=EnsureHttps,
       help="Download url for the currency & funds code list (default: %(default)s)",
   )
   parser_currency.add_argument(
       "--out",
       default=os.path.join(thisDir, "CurrencyDataGenerated.js"),
       help="Output file (default: %(default)s)",
   )
   parser_currency.add_argument(
       "file", nargs="?", help="Local currency code list file, if omitted uses <URL>"
   )
   parser_currency.set_defaults(func=partial(updateCurrency, topsrcdir))

   parser_units = subparsers.add_parser(
       "units", help="Update sanctioned unit identifiers mapping"
   )
   parser_units.set_defaults(func=partial(updateUnits, topsrcdir))

   parser_numbering_systems = subparsers.add_parser(
       "numbering", help="Update numbering systems with simple digit mappings"
   )
   parser_numbering_systems.set_defaults(
       func=partial(updateNumberingSystems, topsrcdir)
   )

   args = parser.parse_args()
   args.func(args)