tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

CSSUnitValue.cpp (3963B)

      1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
      3 /* This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #include "mozilla/dom/CSSUnitValue.h"
      8 
      9 #include "mozilla/AlreadyAddRefed.h"
     10 #include "mozilla/CSSPropertyId.h"
     11 #include "mozilla/ErrorResult.h"
     12 #include "mozilla/RefPtr.h"
     13 #include "mozilla/dom/BindingDeclarations.h"
     14 #include "mozilla/dom/CSSUnitValueBinding.h"
     15 
     16 namespace mozilla::dom {
     17 
     18 CSSUnitValue::CSSUnitValue(nsCOMPtr<nsISupports> aParent, double aValue,
     19                           const nsACString& aUnit)
     20    : CSSNumericValue(std::move(aParent), ValueType::UnitValue),
     21      mValue(aValue),
     22      mUnit(aUnit) {}
     23 
     24 JSObject* CSSUnitValue::WrapObject(JSContext* aCx,
     25                                   JS::Handle<JSObject*> aGivenProto) {
     26  return CSSUnitValue_Binding::Wrap(aCx, this, aGivenProto);
     27 }
     28 
     29 // start of CSSUnitValue Web IDL implementation
     30 
     31 // https://drafts.css-houdini.org/css-typed-om-1/#dom-cssunitvalue-cssunitvalue
     32 //
     33 // static
     34 already_AddRefed<CSSUnitValue> CSSUnitValue::Constructor(
     35    const GlobalObject& aGlobal, double aValue, const nsACString& aUnit,
     36    ErrorResult& aRv) {
     37  // XXX Units should be normalized to lowercase. The Typed OM spec doesn’t
     38  // state this explicitly, but WPT requires lowercase normalization and it
     39  // can also be deduced from the CSS Values spec. Besides fixing it here,
     40  // a spec issue may be needed to clarify this.
     41 
     42  // Step 1.
     43 
     44  // XXX A type should be created from unit and if that fails, the failure
     45  // should be propagated here
     46 
     47  // Step 2.
     48 
     49  return MakeAndAddRef<CSSUnitValue>(aGlobal.GetAsSupports(), aValue, aUnit);
     50 }
     51 
     52 double CSSUnitValue::Value() const { return mValue; }
     53 
     54 void CSSUnitValue::SetValue(double aArg) { mValue = aArg; }
     55 
     56 void CSSUnitValue::GetUnit(nsCString& aRetVal) const { aRetVal = mUnit; }
     57 
     58 // end of CSSUnitValue Web IDL implementation
     59 
     60 void CSSUnitValue::ToCssTextWithProperty(const CSSPropertyId& aPropertyId,
     61                                         nsACString& aDest) const {
     62  // XXX See:
     63  // https://drafts.css-houdini.org/css-typed-om-1/#create-an-internal-representation
     64  //
     65  // The current |isValueOutOfRange| check implements only a minimal subset of
     66  // the algorithm step that wraps out-of-range numeric values (e.g. negative
     67  // perspective) in a calc() expression to keep them representable.
     68  //
     69  // This is a temporary solution until a more robust mechanism is added for
     70  // handling range checks and value wrapping. The long-term plan is to move
     71  // this logic to a dedicated FromTyped trait or similar infrastructure that
     72  // can validate and construct internal representations in a property-aware
     73  // and fully spec-compliant manner. See bug 2005142
     74  const bool isValueOutOfRange = [](NonCustomCSSPropertyId aId, double aValue) {
     75    switch (aId) {
     76      case eCSSProperty_column_width:
     77      case eCSSProperty_perspective:
     78      case eCSSProperty_border_block_end_width:
     79      case eCSSProperty_border_block_start_width:
     80      case eCSSProperty_border_bottom_width:
     81      case eCSSProperty_border_inline_end_width:
     82      case eCSSProperty_border_inline_start_width:
     83      case eCSSProperty_border_left_width:
     84      case eCSSProperty_border_right_width:
     85      case eCSSProperty_border_top_width:
     86      case eCSSProperty_outline_width:
     87        return aValue < 0;
     88 
     89      default:
     90        return false;
     91    }
     92  }(aPropertyId.mId, mValue);
     93 
     94  if (isValueOutOfRange) {
     95    aDest.Append("calc("_ns);
     96  }
     97 
     98  aDest.AppendFloat(mValue);
     99  aDest.Append(mUnit);
    100 
    101  if (isValueOutOfRange) {
    102    aDest.Append(")"_ns);
    103  }
    104 }
    105 
    106 CSSUnitValue& CSSStyleValue::GetAsCSSUnitValue() {
    107  MOZ_DIAGNOSTIC_ASSERT(mValueType == ValueType::UnitValue);
    108 
    109  return *static_cast<CSSUnitValue*>(this);
    110 }
    111 
    112 }  // namespace mozilla::dom