[mathml] Update CSS math-superscript-shift to match the specification

This feature was initially implemented in [1] [2]. After discussion with the CSSWG, the property and values have been renamed [3]. This CL performs the following changes: - Rename math-superscript-shift to math-shift - Rename value "display" and "inline" to "normal" and "compact" - Add a MathML test to verify the effect of CSS math-shift (rather than just testing indirectly via UA style sheet rules). - Sort math-style / math-shift alphabetically [1] https://chromium-review.googlesource.com/c/chromium/src/+/2144185 [2] https://chromium-review.googlesource.com/c/chromium/src/+/2277814 [3] w3c/csswg-drafts#5388 Bug: 6606 Change-Id: I1c7c7c12954261217cafffabffbe044c6659db9e Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2421662 Reviewed-by: Rob Buis <[email protected]> Reviewed-by: Rune Lillesveen <[email protected]> Commit-Queue: Frédéric Wang <[email protected]> Cr-Commit-Position: refs/heads/master@{#809259}
Mu-L · Sep 22, 2020 · c82a21d · c82a21d
1 parent 0ca99fb
commit c82a21d
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Showing 18 changed files with 75 additions and 42 deletions.
diff --git a/third_party/blink/public/mojom/use_counter/css_property_id.mojom b/third_party/blink/public/mojom/use_counter/css_property_id.mojom
@@ -702,7 +702,7 @@ enum CSSSampleId {
     kMathStyle = 656,
     kAspectRatio = 657,
     kAppearance = 658,
-    kMathSuperscriptShiftStyle = 659,
+    // kMathSuperscriptShiftStyle = 659,
     kRubyPosition = 660,
     kTextUnderlineOffset = 661,
     kContentVisibility = 662,
@@ -719,6 +719,7 @@ enum CSSSampleId {
     kDescentOverride = 673,
     kAdvanceOverride = 674,
     kLineGapOverride = 675,
+    kMathShift = 676,
     // 1. Add new features above this line (don't change the assigned numbers of
     //    the existing items).
     // 2. Run the src/tools/metrics/histograms/update_use_counter_css.py script

diff --git a/third_party/blink/renderer/core/css/css_computed_style_declaration.cc b/third_party/blink/renderer/core/css/css_computed_style_declaration.cc
@@ -138,8 +138,8 @@ const CSSPropertyID kComputedPropertyArray[] = {
     CSSPropertyID::kMarginLeft, CSSPropertyID::kMarginRight,
     CSSPropertyID::kMarginTop, CSSPropertyID::kMarkerEnd,
     CSSPropertyID::kMarkerMid, CSSPropertyID::kMarkerStart,
-    CSSPropertyID::kMaskType, CSSPropertyID::kMathStyle,
-    CSSPropertyID::kMathSuperscriptShiftStyle, CSSPropertyID::kMaxBlockSize,
+    CSSPropertyID::kMaskType, CSSPropertyID::kMathShift,
+    CSSPropertyID::kMathStyle, CSSPropertyID::kMaxBlockSize,
     CSSPropertyID::kMaxHeight, CSSPropertyID::kMaxInlineSize,
     CSSPropertyID::kMaxWidth, CSSPropertyID::kMinBlockSize,
     CSSPropertyID::kMinHeight, CSSPropertyID::kMinInlineSize,

diff --git a/third_party/blink/renderer/core/css/css_properties.json5 b/third_party/blink/renderer/core/css/css_properties.json5
@@ -2516,26 +2516,26 @@
       keywords: ["luminance", "alpha"],
       typedom_types: ["Keyword"]
     },
-    // TODO(rbuis): should be moved to high priority later.
     {
-      name: "math-style",
+      name: "math-shift",
       property_methods: ["CSSValueFromComputedStyleInternal"],
       field_template: "keyword",
       inherited: true,
       keywords: ["normal", "compact"],
       typedom_types: ["Keyword"],
       default_value: "normal",
-      runtime_flag: "CSSMathStyle"
+      runtime_flag: "CSSMathShift"
     },
+    // TODO(rbuis): should be moved to high priority later.
     {
-      name: "math-superscript-shift-style",
+      name: "math-style",
       property_methods: ["CSSValueFromComputedStyleInternal"],
       field_template: "keyword",
       inherited: true,
-      keywords: ["inline", "display"],
+      keywords: ["normal", "compact"],
       typedom_types: ["Keyword"],
-      default_value: "display",
-      runtime_flag: "CSSMathSuperscriptShiftStyle"
+      default_value: "normal",
+      runtime_flag: "CSSMathStyle"
     },
     {
       name: "max-height",

diff --git a/third_party/blink/renderer/core/css/css_value_keywords.json5 b/third_party/blink/renderer/core/css/css_value_keywords.json5
@@ -640,15 +640,13 @@
     "wavy",
     "-webkit-nowrap",
 
-    //
-    // math-style
-    //
+    // math-shift
     // normal
     "compact",
 
-    // math-shift
-    // inline
-    "display",
+    // math-style
+    // normal
+    // compact
 
     // CSS3 Values
     // box-align

diff --git a/third_party/blink/renderer/core/css/mathml.css b/third_party/blink/renderer/core/css/mathml.css
@@ -35,7 +35,7 @@
 /* By default, we only display the MathML formulas without any formatting other than the one specified by the display attribute. */
 math {
     display: inline-math;
-    math-superscript-shift-style: display;
+    math-shift: normal;
     math-style: compact;
 }
 
@@ -83,16 +83,16 @@ mfrac > * {
 }
 
 mfrac > :nth-child(2) {
-  math-superscript-shift-style: inline;
+  math-shift: compact;
 }
 
-/* Other rules for scriptlevel, displaystyle and math-superscript-shift-style */
+/* Other rules for scriptlevel, displaystyle and math-shift */
 mroot > :not(:first-child) {
     font-size: scriptlevel(add(2));
     math-style: compact;
 }
 mroot, msqrt {
-    math-superscript-shift-style: inline;
+    math-shift: compact;
 }
 msub > :not(:first-child),
 msup > :not(:first-child),
@@ -116,6 +116,6 @@ munder > :nth-child(2),
 munderover > :nth-child(2),
 mover[accent="true" i] > :first-child,
 munderover[accent="true" i] > :first-child {
-  math-superscript-shift-style: inline;
+  math-shift: compact;
 }
 
diff --git a/third_party/blink/renderer/core/css/parser/css_parser_fast_paths.cc b/third_party/blink/renderer/core/css/parser/css_parser_fast_paths.cc
@@ -668,14 +668,14 @@ bool CSSParserFastPaths::IsValidKeywordPropertyAndValue(
     case CSSPropertyID::kMaskType:
       return value_id == CSSValueID::kLuminance ||
              value_id == CSSValueID::kAlpha;
+    case CSSPropertyID::kMathShift:
+      DCHECK(RuntimeEnabledFeatures::CSSMathShiftEnabled());
+      return value_id == CSSValueID::kNormal ||
+             value_id == CSSValueID::kCompact;
     case CSSPropertyID::kMathStyle:
       DCHECK(RuntimeEnabledFeatures::CSSMathStyleEnabled());
       return value_id == CSSValueID::kNormal ||
              value_id == CSSValueID::kCompact;
-    case CSSPropertyID::kMathSuperscriptShiftStyle:
-      DCHECK(RuntimeEnabledFeatures::CSSMathSuperscriptShiftStyleEnabled());
-      return value_id == CSSValueID::kInline ||
-             value_id == CSSValueID::kDisplay;
     case CSSPropertyID::kObjectFit:
       return value_id == CSSValueID::kFill ||
              value_id == CSSValueID::kContain ||
@@ -1045,8 +1045,8 @@ bool CSSParserFastPaths::IsKeywordPropertyID(CSSPropertyID property_id) {
     case CSSPropertyID::kListStylePosition:
     case CSSPropertyID::kListStyleType:
     case CSSPropertyID::kMaskType:
+    case CSSPropertyID::kMathShift:
     case CSSPropertyID::kMathStyle:
-    case CSSPropertyID::kMathSuperscriptShiftStyle:
     case CSSPropertyID::kObjectFit:
     case CSSPropertyID::kOutlineStyle:
     case CSSPropertyID::kOverflowAnchor:

diff --git a/third_party/blink/renderer/core/css/properties/longhands/longhands_custom.cc b/third_party/blink/renderer/core/css/properties/longhands/longhands_custom.cc
@@ -4083,20 +4083,20 @@ const CSSValue* MaskType::CSSValueFromComputedStyleInternal(
   return CSSIdentifierValue::Create(svg_style.MaskType());
 }
 
-const CSSValue* MathStyle::CSSValueFromComputedStyleInternal(
+const CSSValue* MathShift::CSSValueFromComputedStyleInternal(
     const ComputedStyle& style,
     const SVGComputedStyle&,
     const LayoutObject*,
     bool allow_visited_style) const {
-  return CSSIdentifierValue::Create(style.MathStyle());
+  return CSSIdentifierValue::Create(style.MathShift());
 }
 
-const CSSValue* MathSuperscriptShiftStyle::CSSValueFromComputedStyleInternal(
+const CSSValue* MathStyle::CSSValueFromComputedStyleInternal(
     const ComputedStyle& style,
     const SVGComputedStyle&,
     const LayoutObject*,
     bool allow_visited_style) const {
-  return CSSIdentifierValue::Create(style.MathSuperscriptShiftStyle());
+  return CSSIdentifierValue::Create(style.MathStyle());
 }
 
 const CSSValue* MaxBlockSize::ParseSingleValue(

diff --git a/third_party/blink/renderer/core/layout/ng/mathml/ng_math_scripts_layout_algorithm.cc b/third_party/blink/renderer/core/layout/ng/mathml/ng_math_scripts_layout_algorithm.cc
@@ -197,8 +197,7 @@ NGMathScriptsLayoutAlgorithm::GetVerticalMetrics(
   if (type == MathScriptType::kSuper || type == MathScriptType::kSubSup ||
       type == MathScriptType::kMultiscripts || type == MathScriptType::kOver ||
       type == MathScriptType::kMultiscripts) {
-    if (Style().MathSuperscriptShiftStyle() ==
-        EMathSuperscriptShiftStyle::kInline)
+    if (Style().MathShift() == EMathShift::kCompact)
       shift_up = parameters.superscript_shift_up_cramped;
     metrics.sup_shift =
         std::max(shift_up, base_metrics.ascent -

diff --git a/third_party/blink/renderer/platform/runtime_enabled_features.json5 b/third_party/blink/renderer/platform/runtime_enabled_features.json5
@@ -514,12 +514,12 @@
       name: "CSSMatchedPropertiesCacheDependencies",
     },
     {
-      name: "CSSMathStyle",
+      name: "CSSMathShift",
       status: "experimental",
       implied_by: ["MathMLCore"],
     },
     {
-      name: "CSSMathSuperscriptShiftStyle",
+      name: "CSSMathStyle",
       status: "experimental",
       implied_by: ["MathMLCore"],
     },

diff --git a/third_party/blink/web_tests/external/wpt/mathml/presentation-markup/scripts/cramped-001.html b/third_party/blink/web_tests/external/wpt/mathml/presentation-markup/scripts/cramped-001.html
@@ -8,7 +8,7 @@
 <link rel="help" href="https://mathml-refresh.github.io/mathml-core/#radicals-msqrt-mroot">
 <link rel="help" href="https://mathml-refresh.github.io/mathml-core/#displaystyle-and-scriptlevel-in-scripts">
 <link rel="help" href="https://mathml-refresh.github.io/mathml-core/#user-agent-stylesheet">
-<meta name="assert" content="Verify default calculation of math-superscript-shift-style on MathML elements">
+<meta name="assert" content="Verify default calculation of math-shift on MathML elements">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <script src="/mathml/support/feature-detection.js"></script>
@@ -138,6 +138,14 @@
           assert_cramped("mmultiscripts-005", false, "post-superscript");
       }, "mmultiscripts");
 
+      test(function() {
+          assert_true(MathMLFeatureDetection.has_mspace());
+          assert_cramped("css-001", false);
+          assert_cramped("css-002", true);
+          assert_cramped("css-003", true);
+          assert_cramped("css-004", false);
+      }, "element with specified CSS math-style");
+
       done();
   }
 </script>
@@ -588,5 +596,31 @@
       </mmultiscripts>
     </math>
   </p>
+  <p>
+    <math id="css-001" style="math-shift: normal">
+      <msup class="testedElement">
+        <mspace height="2em" width="2em"/>
+        <mspace height="1em" width="1em"/>
+      </msup>
+    </math>
+    <math id="css-002" style="math-shift: compact">
+      <msup class="testedElement">
+        <mspace height="2em" width="2em"/>
+        <mspace height="1em" width="1em"/>
+      </msup>
+    </math>
+    <math id="css-003" style="math-shift: normal">
+      <msup class="testedElement" style="math-shift: compact">
+        <mspace height="2em" width="2em"/>
+        <mspace height="1em" width="1em"/>
+      </msup>
+    </math>
+    <math id="css-004" style="math-shift: compact">
+      <msup class="testedElement" style="math-shift: normal">
+        <mspace height="2em" width="2em"/>
+        <mspace height="1em" width="1em"/>
+      </msup>
+    </math>
+  </p>
 </body>
 </html>
diff --git a/third_party/blink/web_tests/fast/css/getComputedStyle/computed-style-listing-expected.txt b/third_party/blink/web_tests/fast/css/getComputedStyle/computed-style-listing-expected.txt
@@ -214,8 +214,8 @@ marker-end: none
 marker-mid: none
 marker-start: none
 mask-type: luminance
+math-shift: normal
 math-style: normal
-math-superscript-shift-style: display
 max-block-size: none
 max-height: none
 max-inline-size: none

diff --git a/.../web_tests/fast/css/getComputedStyle/computed-style-without-renderer-listing-expected.txt b/.../web_tests/fast/css/getComputedStyle/computed-style-without-renderer-listing-expected.txt
@@ -214,8 +214,8 @@ marker-end: none
 marker-mid: none
 marker-start: none
 mask-type: luminance
+math-shift: normal
 math-style: normal
-math-superscript-shift-style: display
 max-block-size: none
 max-height: none
 max-inline-size: none

diff --git a/...nk/web_tests/platform/mac/external/wpt/css/cssom/cssstyledeclaration-csstext-expected.txt b/...nk/web_tests/platform/mac/external/wpt/css/cssom/cssstyledeclaration-csstext-expected.txt
diff --git a/...nk/web_tests/platform/win/external/wpt/css/cssom/cssstyledeclaration-csstext-expected.txt b/...nk/web_tests/platform/win/external/wpt/css/cssom/cssstyledeclaration-csstext-expected.txt
diff --git a/third_party/blink/web_tests/svg/css/getComputedStyle-listing-expected.txt b/third_party/blink/web_tests/svg/css/getComputedStyle-listing-expected.txt
@@ -214,8 +214,8 @@ marker-end: none
 marker-mid: none
 marker-start: none
 mask-type: luminance
+math-shift: normal
 math-style: normal
-math-superscript-shift-style: display
 max-block-size: none
 max-height: none
 max-inline-size: none

diff --git a/third_party/blink/web_tests/webexposed/css-properties-as-js-properties-expected.txt b/third_party/blink/web_tests/webexposed/css-properties-as-js-properties-expected.txt
@@ -240,8 +240,8 @@ markerMid
 markerStart
 mask
 maskType
+mathShift
 mathStyle
-mathSuperscriptShiftStyle
 maxBlockSize
 maxHeight
 maxInlineSize

diff --git a/third_party/blink/web_tests/webexposed/css-property-listing-expected.txt b/third_party/blink/web_tests/webexposed/css-property-listing-expected.txt
@@ -232,8 +232,8 @@ All changes to this list should go through Blink's feature review process: http:
     marker-start
     mask
     mask-type
+    math-shift
     math-style
-    math-superscript-shift-style
     max-block-size
     max-height
     max-inline-size

diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
@@ -46289,6 +46289,7 @@ Called by update_use_counter_css.py.-->
   <int value="673" label="descent-override"/>
   <int value="674" label="advance-override"/>
   <int value="675" label="line-gap-override"/>
+  <int value="676" label="math-shift"/>
 </enum>
 
 <enum name="MappedEditingCommands">