From a149af11997a31d68491f1942147a7a2fb50db45 Mon Sep 17 00:00:00 2001
From: Moonchild <moonchild@palemoon.org>
Date: Sat, 12 Jun 2021 11:36:16 +0000
Subject: [PATCH] Issue #1781 - Part 2: Fix animation interpolation for
 stroke-dashoffset.

Since we have calc() and floats working now, this is a trivial fix.
---
 layout/style/StyleAnimationValue.cpp | 14 ++++++++++++--
 layout/style/nsCSSPropList.h         |  3 ++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/layout/style/StyleAnimationValue.cpp b/layout/style/StyleAnimationValue.cpp
index ff67835536..2332de6a6a 100644
--- a/layout/style/StyleAnimationValue.cpp
+++ b/layout/style/StyleAnimationValue.cpp
@@ -63,11 +63,15 @@ GetCommonUnit(nsCSSPropertyID aProperty,
               StyleAnimationValue::Unit aSecondUnit)
 {
   if (aFirstUnit != aSecondUnit) {
+    bool numberAsPixel =
+      nsCSSProps::PropHasFlags(aProperty, CSS_PROPERTY_NUMBERS_ARE_PIXELS);
     if (nsCSSProps::PropHasFlags(aProperty, CSS_PROPERTY_STORES_CALC) &&
-        (aFirstUnit == StyleAnimationValue::eUnit_Coord ||
+        ((aFirstUnit == StyleAnimationValue::eUnit_Float && numberAsPixel) ||
+         aFirstUnit == StyleAnimationValue::eUnit_Coord ||
          aFirstUnit == StyleAnimationValue::eUnit_Percent ||
          aFirstUnit == StyleAnimationValue::eUnit_Calc) &&
-        (aSecondUnit == StyleAnimationValue::eUnit_Coord ||
+        ((aSecondUnit == StyleAnimationValue::eUnit_Float && numberAsPixel) ||
+         aSecondUnit == StyleAnimationValue::eUnit_Coord ||
          aSecondUnit == StyleAnimationValue::eUnit_Percent ||
          aSecondUnit == StyleAnimationValue::eUnit_Calc)) {
       // We can use calc() as the common unit.
@@ -354,6 +358,12 @@ ExtractCalcValue(const StyleAnimationValue& aValue)
     result.mHasPercent = true;
     return result;
   }
+  if (aValue.GetUnit() == StyleAnimationValue::eUnit_Float) {
+    result.mLength = aValue.GetFloatValue();
+    result.mPercent = 0.0f;
+    result.mHasPercent = false;
+    return result;
+  }
   MOZ_ASSERT(aValue.GetUnit() == StyleAnimationValue::eUnit_Calc,
              "unexpected unit");
   nsCSSValue *val = aValue.GetCSSValueValue();
diff --git a/layout/style/nsCSSPropList.h b/layout/style/nsCSSPropList.h
index f0cab6b131..45e919d4f8 100644
--- a/layout/style/nsCSSPropList.h
+++ b/layout/style/nsCSSPropList.h
@@ -3814,7 +3814,8 @@ CSS_PROP_SVG(
     stroke_dashoffset,
     StrokeDashoffset,
     CSS_PROPERTY_PARSE_VALUE |
-        CSS_PROPERTY_NUMBERS_ARE_PIXELS,
+        CSS_PROPERTY_NUMBERS_ARE_PIXELS |
+        CSS_PROPERTY_STORES_CALC,
     "",
     VARIANT_HLPN | VARIANT_OPENTYPE_SVG_KEYWORD | VARIANT_CALC,
     kStrokeContextValueKTable,