Bug 1529572 - Should resolve absolute units r=longsonr

Firefox only failure.

Differential Revision: https://phabricator.services.mozilla.com/D35614

--HG--
extra : moz-landing-system : lando

dom/svg/DOMSVGLength.cpp

@@ -213,10 +213,12 @@ float DOMSVGLength::GetValue(ErrorResult& aRv) {
     }
     return value;
   }
-  if (mUnit == SVGLength_Binding::SVG_LENGTHTYPE_NUMBER ||
-      mUnit == SVGLength_Binding::SVG_LENGTHTYPE_PX) {
-    return mValue;
+
+  float unitToPx;
+  if (UserSpaceMetrics::ResolveAbsoluteUnit(mUnit, unitToPx)) {
+    return mValue * unitToPx;
   }
+
   // else [SVGWG issue] Can't convert this length's value to user units
   // ReportToConsole
   aRv.Throw(NS_ERROR_FAILURE);

dom/svg/SVGAnimatedLength.cpp

@@ -204,22 +204,40 @@ float SVGAnimatedLength::GetPixelsPerUnit(nsIFrame* aFrame,
 // See https://www.w3.org/TR/css-values-3/#absolute-lengths
 static const float DPI = 96.0f;
 
-float SVGAnimatedLength::GetPixelsPerUnit(const UserSpaceMetrics& aMetrics,
-                                          uint8_t aUnitType) const {
+bool UserSpaceMetrics::ResolveAbsoluteUnit(uint8_t aUnitType, float& aRes) {
   switch (aUnitType) {
     case SVGLength_Binding::SVG_LENGTHTYPE_NUMBER:
     case SVGLength_Binding::SVG_LENGTHTYPE_PX:
-      return 1;
+      aRes = 1;
+      break;
     case SVGLength_Binding::SVG_LENGTHTYPE_MM:
-      return DPI / MM_PER_INCH_FLOAT;
+      aRes = DPI / MM_PER_INCH_FLOAT;
+      break;
     case SVGLength_Binding::SVG_LENGTHTYPE_CM:
-      return 10.0f * DPI / MM_PER_INCH_FLOAT;
+      aRes = 10.0f * DPI / MM_PER_INCH_FLOAT;
+      break;
     case SVGLength_Binding::SVG_LENGTHTYPE_IN:
-      return DPI;
+      aRes = DPI;
+      break;
     case SVGLength_Binding::SVG_LENGTHTYPE_PT:
-      return DPI / POINTS_PER_INCH_FLOAT;
+      aRes = DPI / POINTS_PER_INCH_FLOAT;
+      break;
     case SVGLength_Binding::SVG_LENGTHTYPE_PC:
-      return 12.0f * DPI / POINTS_PER_INCH_FLOAT;
+      aRes = 12.0f * DPI / POINTS_PER_INCH_FLOAT;
+      break;
+    default:
+      return false;
+  }
+  return true;
+}
+
+float SVGAnimatedLength::GetPixelsPerUnit(const UserSpaceMetrics& aMetrics,
+                                          uint8_t aUnitType) const {
+  float res;
+  if (UserSpaceMetrics::ResolveAbsoluteUnit(aUnitType, res)) {
+    return res;
+  }
+  switch (aUnitType) {
     case SVGLength_Binding::SVG_LENGTHTYPE_PERCENTAGE:
       return aMetrics.GetAxisLength(mCtxType) / 100.0f;
     case SVGLength_Binding::SVG_LENGTHTYPE_EMS:

dom/svg/SVGAnimatedLength.h

@@ -33,6 +33,7 @@ class SVGViewportElement;
 
 class UserSpaceMetrics {
  public:
+  static bool ResolveAbsoluteUnit(uint8_t aUnitType, float& aRes);
   virtual ~UserSpaceMetrics() = default;
 
   virtual float GetEmLength() const = 0;

testing/web-platform/meta/svg/types/scripted/SVGLength-px.html.ini

@@ -7,19 +7,3 @@
 
   [SVGLength, converting from 'px' to other units (detached), exs]
     expected: FAIL
-
-  [SVGLength, converting from 'px' to other units (detached), cm]
-    expected: FAIL
-
-  [SVGLength, converting from 'px' to other units (detached), mm]
-    expected: FAIL
-
-  [SVGLength, converting from 'px' to other units (detached), in]
-    expected: FAIL
-
-  [SVGLength, converting from 'px' to other units (detached), pt]
-    expected: FAIL
-
-  [SVGLength, converting from 'px' to other units (detached), pc]
-    expected: FAIL
-

testing/web-platform/tests/svg/types/scripted/SVGLength-px.html

@@ -72,7 +72,7 @@ test(function() {
   var referenceValue = 48 * 2.54 / cssPixelsPerInch;
   assert_equals(length.valueAsString, referenceValue.toFixed(2) + "cm");
   assert_approx_equals(length.valueInSpecifiedUnits, referenceValue, 0.01);
-  assert_equals(length.value, 48);
+  assert_approx_equals(length.value, 48, 0.001);
   assert_equals(length.unitType, SVGLength.SVG_LENGTHTYPE_CM);
 }, document.title + ", cm");
 
@@ -119,4 +119,4 @@ test(function() {
   assert_equals(length.value, 16);
   assert_equals(length.unitType, SVGLength.SVG_LENGTHTYPE_PC);
 }, document.title + ", pc");
-</script>
+</script>