commit a0b750c5fc0df2f7ab481542365d24cc42645465
parent 934a439e0e1655d0ee64b28ce6cdfea7db3dd35b
Author: serge-sans-paille <sguelton@mozilla.com>
Date: Tue, 16 Dec 2025 13:47:13 +0000
Bug 2002798 - Shortpath for find_variables_from_ast r=ahochheiden
It's very common to ask for variables that are not present in many
moz.build files. In that case we can perform a fast quick check through
regular expression before parsing the actual files.
This speeds up taskgraph construction by 500ms.
Differential Revision: https://phabricator.services.mozilla.com/D274298
Diffstat:
1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/python/mozbuild/mozbuild/frontend/reader.py b/python/mozbuild/mozbuild/frontend/reader.py
@@ -21,6 +21,7 @@ import functools
import inspect
import logging
import os
+import re
import sys
import textwrap
import time
@@ -996,10 +997,11 @@ class BuildReader:
<variable name>, <key>, <value>)`. The `key` will only be
defined if the variable is an object, otherwise it is `None`.
"""
-
if isinstance(variables, str):
variables = [variables]
+ variables_matcher = re.compile("|".join(variables))
+
def assigned_variable(node):
# This is not correct, but we don't care yet.
if hasattr(node, "targets"):
@@ -1080,12 +1082,17 @@ class BuildReader:
mozbuild_paths = self.all_mozbuild_paths()
for p in mozbuild_paths:
- assignments[:] = []
full = os.path.join(self.config.topsrcdir, p)
- with open(full, "rb") as fh:
+ with open(full) as fh:
source = fh.read()
+ # No need to do the heavy parsing if there is no literal mention of
+ # the variables
+ if not re.search(variables_matcher, source):
+ continue
+
+ assignments[:] = []
tree = ast.parse(source, full)
Visitor().visit(tree)
