Don't wrap min/max() in calc() in CSS value serialization

Bug: 825895 Change-Id: I98e3327a82352a90db9a74b1adc4b62ffd54c4ee Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1758834Reviewed-by: Emil A Eklund <eae@chromium.org> Reviewed-by: Rune Lillesveen <futhark@chromium.org> Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org> Cr-Commit-Position: refs/heads/master@{#688263}

Don't wrap min/max() in calc() in CSS value serialization
Bug: 825895 Change-Id: I98e3327a82352a90db9a74b1adc4b62ffd54c4ee Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1758834Reviewed-by: Emil A Eklund <eae@chromium.org> Reviewed-by: Rune Lillesveen <futhark@chromium.org> Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org> Cr-Commit-Position: refs/heads/master@{#688263}
b8807c89 · Xiaocheng Hu · Commit Bot · f83cf95a · b8807c89 · b8807c89
Commit b8807c89 authored Aug 19, 2019 by Xiaocheng Hu Committed by Commit Bot Aug 19, 2019
3 changed files
--- a/third_party/blink/renderer/core/css/css_math_expression_node.h
+++ b/third_party/blink/renderer/core/css/css_math_expression_node.h
@@ -76,6 +76,10 @@ class CORE_EXPORT CSSMathExpressionNode
  virtual bool IsBinaryOperation() const { return false; }
  virtual bool IsVariadicOperation() const { return false; }

+  bool IsMathFunction() const {
+    return !IsNumericLiteral() && !IsBinaryOperation();
+  }
+
  virtual bool IsZero() const = 0;

  // Resolves the expression into one value *without doing any type conversion*.

--- a/third_party/blink/renderer/core/css/css_math_function_value.cc
+++ b/third_party/blink/renderer/core/css/css_math_function_value.cc
@@ -97,7 +97,13 @@ static String BuildCSSText(const String& expression) {
 }

 String CSSMathFunctionValue::CustomCSSText() const {
-  return BuildCSSText(expression_->CustomCSSText());
+  const String& expression_text = expression_->CustomCSSText();
+  if (expression_->IsMathFunction()) {
+    // If |expression_| is already a math function (e.g., min/max), we don't
+    // need to wrap it in |calc()|.
+    return expression_text;
+  }
+  return BuildCSSText(expression_text);
 }

 bool CSSMathFunctionValue::Equals(const CSSMathFunctionValue& other) const {

--- a/third_party/blink/web_tests/external/wpt/css/css-values/minmax-angle-serialize.html
+++ b/third_party/blink/web_tests/external/wpt/css/css-values/minmax-angle-serialize.html
+<!DOCTYPE html>
+<link rel="help" href="https://drafts.csswg.org/css-values-4/#comp-func">
+<link rel="help" href="https://drafts.csswg.org/css-values-4/#angles">
+<link rel="help" href="https://drafts.csswg.org/css-values-4/#calc-type-checking">
+<link rel="author" title="Xiaocheng Hu" href="mailto:xiaochengh@chromium.org">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../support/parsing-testcommon.js"></script>
+<script>
+function test_valid_angle(value, expected) {
+  test_valid_value('transform', `rotate(${value})`, `rotate(${expected})`);
+}
+
+test_valid_angle('min(1deg)', 'min(1deg)');
+test_valid_angle('min(1rad)', 'min(1rad)');
+test_valid_angle('min(1turn)', 'min(1turn)');
+test_valid_angle('min(1grad)', 'min(1grad)');
+test_valid_angle('max(1deg)', 'max(1deg)');
+test_valid_angle('max(1rad)', 'max(1rad)');
+test_valid_angle('max(1turn)', 'max(1turn)');
+test_valid_angle('max(1grad)', 'max(1grad)');
+
+// TODO(crbug.com/978682): Complete this test suite
+
+</script>