Only allow calc() combinations as per spec.

We allowed calc expressions combining numbers and lengths, numbers and
percentages, and even a combination of numbers, percentages, and
lengths. None of those are allowed per the CSS Values and Units spec,
and it made it possible to combine user units, lengths, and percentages
into the same calc() for certain SVG CSS properties and attributes.

See also: w3c/csswg-drafts#4874

This improves SVG interop with Firefox. Firefox does not support calc()
for numbers, though.

Bug: 1061714
Change-Id: I9e5c492122242e51064310a40e28a233530e357c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2134251
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Reviewed-by: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#756226}

third_party/blink/renderer/core/css/css_math_expression_node.cc

@@ -229,10 +229,7 @@ double CSSMathExpressionNumericLiteral::ComputeLengthPx(
     case kCalcAngle:
     case kCalcFrequency:
     case kCalcPercentLength:
-    case kCalcPercentNumber:
     case kCalcTime:
-    case kCalcLengthNumber:
-    case kCalcPercentLengthNumber:
     case kCalcOther:
       NOTREACHED();
       break;
@@ -285,43 +282,26 @@ bool CSSMathExpressionNumericLiteral::InvolvesPercentageComparisons() const {
 // ------ End of CSSMathExpressionNumericLiteral member functions
 
 static const CalculationCategory kAddSubtractResult[kCalcOther][kCalcOther] = {
-    /* CalcNumber */ {kCalcNumber, kCalcLengthNumber, kCalcPercentNumber,
-                      kCalcPercentNumber, kCalcOther, kCalcOther, kCalcOther,
-                      kCalcOther, kCalcLengthNumber, kCalcPercentLengthNumber},
+    /* CalcNumber */ {kCalcNumber, kCalcOther, kCalcOther, kCalcOther,
+                      kCalcOther, kCalcOther, kCalcOther},
     /* CalcLength */
-    {kCalcLengthNumber, kCalcLength, kCalcPercentLength, kCalcOther,
-     kCalcPercentLength, kCalcOther, kCalcOther, kCalcOther, kCalcLengthNumber,
-     kCalcPercentLengthNumber},
+    {kCalcOther, kCalcLength, kCalcPercentLength, kCalcPercentLength,
+     kCalcOther, kCalcOther, kCalcOther},
     /* CalcPercent */
-    {kCalcPercentNumber, kCalcPercentLength, kCalcPercent, kCalcPercentNumber,
-     kCalcPercentLength, kCalcOther, kCalcOther, kCalcOther,
-     kCalcPercentLengthNumber, kCalcPercentLengthNumber},
-    /* CalcPercentNumber */
-    {kCalcPercentNumber, kCalcPercentLengthNumber, kCalcPercentNumber,
-     kCalcPercentNumber, kCalcPercentLengthNumber, kCalcOther, kCalcOther,
-     kCalcOther, kCalcOther, kCalcPercentLengthNumber},
+    {kCalcOther, kCalcPercentLength, kCalcPercent, kCalcPercentLength,
+     kCalcOther, kCalcOther, kCalcOther},
     /* CalcPercentLength */
-    {kCalcPercentLengthNumber, kCalcPercentLength, kCalcPercentLength,
-     kCalcPercentLengthNumber, kCalcPercentLength, kCalcOther, kCalcOther,
-     kCalcOther, kCalcOther, kCalcPercentLengthNumber},
+    {kCalcOther, kCalcPercentLength, kCalcPercentLength, kCalcPercentLength,
+     kCalcOther, kCalcOther, kCalcOther},
     /* CalcAngle  */
-    {kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcAngle,
-     kCalcOther, kCalcOther, kCalcOther, kCalcOther},
+    {kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcAngle, kCalcOther,
+     kCalcOther},
     /* CalcTime */
-    {kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther,
-     kCalcTime, kCalcOther, kCalcOther, kCalcOther},
+    {kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcTime,
+     kCalcOther},
     /* CalcFrequency */
     {kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther, kCalcOther,
-     kCalcOther, kCalcFrequency, kCalcOther, kCalcOther},
-    /* CalcLengthNumber */
-    {kCalcLengthNumber, kCalcLengthNumber, kCalcPercentLengthNumber,
-     kCalcPercentLengthNumber, kCalcPercentLengthNumber, kCalcOther, kCalcOther,
-     kCalcOther, kCalcLengthNumber, kCalcPercentLengthNumber},
-    /* CalcPercentLengthNumber */
-    {kCalcPercentLengthNumber, kCalcPercentLengthNumber,
-     kCalcPercentLengthNumber, kCalcPercentLengthNumber,
-     kCalcPercentLengthNumber, kCalcOther, kCalcOther, kCalcOther,
-     kCalcPercentLengthNumber, kCalcPercentLengthNumber}};
+     kCalcFrequency}};
 
 static CalculationCategory DetermineCategory(
     const CSSMathExpressionNode& left_side,
@@ -729,9 +709,6 @@ CSSPrimitiveValue::UnitType CSSMathExpressionBinaryOperation::ResolvedUnitType()
     case kCalcFrequency:
       return CSSPrimitiveValue::UnitType::kHertz;
     case kCalcPercentLength:
-    case kCalcPercentNumber:
-    case kCalcLengthNumber:
-    case kCalcPercentLengthNumber:
     case kCalcOther:
       return CSSPrimitiveValue::UnitType::kUnknown;
   }

third_party/blink/renderer/core/css/css_math_expression_node.h

@@ -47,17 +47,14 @@ class CSSNumericLiteralValue;
 // The order of this enum should not change since its elements are used as
 // indices in the addSubtractResult matrix.
 enum CalculationCategory {
-  kCalcNumber = 0,
+  kCalcNumber,
   kCalcLength,
   kCalcPercent,
-  kCalcPercentNumber,
   kCalcPercentLength,
   kCalcAngle,
   kCalcTime,
   kCalcFrequency,
-  kCalcLengthNumber,
-  kCalcPercentLengthNumber,
-  kCalcOther
+  kCalcOther,
 };
 
 class CORE_EXPORT CSSMathExpressionNode
@@ -121,9 +118,7 @@ class CORE_EXPORT CSSMathExpressionNode
 
   CalculationCategory Category() const { return category_; }
   bool HasPercentage() const {
-    return category_ == kCalcPercent || category_ == kCalcPercentNumber ||
-           category_ == kCalcPercentLength ||
-           category_ == kCalcPercentLengthNumber;
+    return category_ == kCalcPercent || category_ == kCalcPercentLength;
   }
 
   // Returns the unit type of the math expression *without doing any type

third_party/blink/renderer/core/css/parser/css_property_parser_helpers.cc

@@ -470,18 +470,9 @@ CSSPrimitiveValue* ConsumeAlphaValue(CSSParserTokenRange& range,
 
 bool CanConsumeCalcValue(CalculationCategory category,
                          CSSParserMode css_parser_mode) {
-  if (category == kCalcLength || category == kCalcPercent ||
-      category == kCalcPercentLength)
-    return true;
-
-  if (css_parser_mode != kSVGAttributeMode)
-    return false;
-
-  if (category == kCalcNumber || category == kCalcPercentNumber ||
-      category == kCalcLengthNumber || category == kCalcPercentLengthNumber)
-    return true;
-
-  return false;
+  return category == kCalcLength || category == kCalcPercent ||
+         category == kCalcPercentLength ||
+         (css_parser_mode == kSVGAttributeMode && category == kCalcNumber);
 }
 
 CSSPrimitiveValue* ConsumeLengthOrPercent(CSSParserTokenRange& range,
@@ -512,16 +503,7 @@ bool IsNonZeroUserUnitsValue(const CSSPrimitiveValue* value) {
            value->GetDoubleValue() != 0;
   }
   const auto& math_value = To<CSSMathFunctionValue>(*value);
-  switch (math_value.Category()) {
-    case kCalcNumber:
-      return math_value.DoubleValue() != 0;
-    case kCalcPercentNumber:
-    case kCalcLengthNumber:
-    case kCalcPercentLengthNumber:
-      return true;
-    default:
-      return false;
-  }
+  return math_value.Category() == kCalcNumber && math_value.DoubleValue() != 0;
 }
 
 }  // namespace

third_party/blink/renderer/core/svg/svg_length.cc

@@ -165,10 +165,7 @@ static bool IsSupportedCalculationCategory(CalculationCategory category) {
     case kCalcLength:
     case kCalcNumber:
     case kCalcPercent:
-    case kCalcPercentNumber:
     case kCalcPercentLength:
-    case kCalcLengthNumber:
-    case kCalcPercentLengthNumber:
       return true;
     default:
       return false;

third_party/blink/web_tests/animations/svg-attribute-interpolation/svg-calc-interpolation.html

@@ -40,13 +40,13 @@
   from: '0%',
   to: '100'
 }, [
-  {at: -0.25, is: 'calc(0% + -25)'},
+  {at: -0.25, is: 'calc(0% + -25px)'},
   {at: 0, is: '0%'},
-  {at: 0.25, is: 'calc(0% + 25)'},
-  {at: 0.5, is: 'calc(0% + 50)'},
-  {at: 0.75, is: 'calc(0% + 75)'},
+  {at: 0.25, is: 'calc(0% + 25px)'},
+  {at: 0.5, is: 'calc(0% + 50px)'},
+  {at: 0.75, is: 'calc(0% + 75px)'},
   {at: 1, is: '100px'},
-  {at: 1.25, is: 'calc(0% + 125)'}
+  {at: 1.25, is: 'calc(0% + 125px)'}
 ]);
 assertAttributeInterpolation({
   property: 'cy',

third_party/blink/web_tests/external/wpt/svg/animations/svglength-additive-by-8.html

@@ -13,8 +13,8 @@
 <!-- an1: Change width from 10 to 50 in 4s -->
 <!-- an2: Change width from 10 to 100 in 4s starting at 5s -->
 <rect width="10" height="100" fill="green">
-    <animate id="an1" attributeType="XML" attributeName="width" fill="remove" by="calc(4% + 8)" begin="0s" dur="4s"/>
-        <animate id="an2" attributeType="XML" attributeName="width" additive="replace" fill="freeze" by="calc(10% + 10)" begin="5s" dur="4s"/>
+    <animate id="an1" attributeType="XML" attributeName="width" fill="remove" by="calc(4% + 8px)" begin="0s" dur="4s"/>
+        <animate id="an2" attributeType="XML" attributeName="width" additive="replace" fill="freeze" by="calc(10% + 10px)" begin="5s" dur="4s"/>
 </rect>
 
 </svg>
@@ -73,4 +73,4 @@
 
 window.animationStartsImmediately = true;
 
-</script>
+</script>

third_party/blink/web_tests/external/wpt/svg/painting/parsing/stroke-dashoffset-valid-expected.txt

@@ -5,5 +5,8 @@ PASS e.style['stroke-dashoffset'] = "-20%" should set the property value
 FAIL e.style['stroke-dashoffset'] = "30" should set the property value assert_equals: serialization should be canonical expected "30px" but got "30"
 PASS e.style['stroke-dashoffset'] = "40Q" should set the property value
 PASS e.style['stroke-dashoffset'] = "calc(2em + 3ex)" should set the property value
+PASS e.style['stroke-dashoffset'] = "calc(3)" should set the property value
+PASS e.style['stroke-dashoffset'] = "calc(2 + 1)" should set the property value
+PASS e.style['stroke-dashoffset'] = "calc(2 + (7 - 5))" should set the property value
 Harness: the test ran to completion.
 

third_party/blink/web_tests/external/wpt/svg/painting/parsing/stroke-width-valid-expected.txt

@@ -6,5 +6,8 @@ PASS e.style['stroke-width'] = "calc(2em + 3ex)" should set the property value
 PASS e.style['stroke-width'] = "4%" should set the property value
 PASS e.style['stroke-width'] = "5vmin" should set the property value
 PASS e.style['stroke-width'] = "calc(50% + 60px)" should set the property value
+PASS e.style['stroke-width'] = "calc(3)" should set the property value
+PASS e.style['stroke-width'] = "calc(2 + 1)" should set the property value
+PASS e.style['stroke-width'] = "calc(2 + (7 - 5))" should set the property value
 Harness: the test ran to completion.
 

third_party/blink/web_tests/svg/custom/calc-expression-with-zoom.html

@@ -3,6 +3,6 @@
    body { zoom: 200%; }
 </style>
 <svg id="svg" width="500" height="500" viewBox='0 0 1000 1000'>
-    <rect width='calc(50px + 50)' height='100' fill='green'/>
+    <rect width='calc(50px + 50px)' height='100' fill='green'/>
     <rect x='110' width='calc(50 + 50)' height='100' fill='green'/>
 </svg> 

third_party/blink/web_tests/svg/dom/SVGLength-calc-in-attr.html

@@ -82,10 +82,10 @@
     assert_calc_expression("calc(10mm + 10mm)", (20 * cssPixelsPerMillimeter));
     assert_calc_expression("calc(20mm)", (20 * cssPixelsPerMillimeter));
     assert_calc_expression("calc(10 + 10)", 20);
-    assert_calc_expression("calc(10mm + 10)", (10 * cssPixelsPerMillimeter) + 10);
-    assert_calc_expression("calc(10% + 10)", (10 * viewportWidthPercent()) + 10);
-    assert_calc_expression("calc(1cm + 2in + 1cm + 2)", (2 * cssPixelsPerInch) + (2 * cssPixelsPerCentimeter) + 2);
-    assert_calc_expression("calc(1cm + 2 + 1cm + 2in)", (2 * cssPixelsPerInch) + (2 * cssPixelsPerCentimeter) + 2);
-    assert_calc_expression("calc(10% + 10 + 2% + 10pc)", (12 * viewportWidthPercent()) + 10 + (10 * cssPixelsPerPica));
+    assert_calc_expression("calc(10mm + 10px)", (10 * cssPixelsPerMillimeter) + 10);
+    assert_calc_expression("calc(10% + 10px)", (10 * viewportWidthPercent()) + 10);
+    assert_calc_expression("calc(1cm + 2in + 1cm + 2px)", (2 * cssPixelsPerInch) + (2 * cssPixelsPerCentimeter) + 2);
+    assert_calc_expression("calc(1cm + 2px + 1cm + 2in)", (2 * cssPixelsPerInch) + (2 * cssPixelsPerCentimeter) + 2);
+    assert_calc_expression("calc(10% + 10px + 2% + 10pc)", (12 * viewportWidthPercent()) + 10 + (10 * cssPixelsPerPica));
 }, "Tests calc() on presentation and non-presentation attr in svgLength");
 </script>