Bug 1392722: Allow zero in rotateFromVector r=bzbarsky

Aligns to the spec. Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=f7c12c831fb8a6ce0d5ec6b31fcf1f708464deaf Differential Revision: https://phabricator.services.mozilla.com/D36748 --HG-- extra : moz-landing-system : lando
dothq · Jul 4, 2019 · 95687d2 · 95687d2
1 parent c9de23a
commit 95687d2
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Showing 3 changed files with 21 additions and 7 deletions.
diff --git a/dom/base/DOMMatrix.cpp b/dom/base/DOMMatrix.cpp
@@ -848,11 +848,7 @@ DOMMatrix* DOMMatrix::Scale3dSelf(double aScale, double aOriginX,
 }
 
 DOMMatrix* DOMMatrix::RotateFromVectorSelf(double aX, double aY) {
-  if (aX == 0.0 || aY == 0.0) {
-    return this;
-  }
-
-  const double angle = atan2(aY, aX);
+  const double angle = (aX == 0.0 && aY == 0.0) ? 0 : atan2(aY, aX);
 
   if (fmod(angle, 2 * M_PI) == 0) {
     return this;

diff --git a/dom/webidl/DOMMatrix.webidl b/dom/webidl/DOMMatrix.webidl
@@ -99,8 +99,8 @@ interface DOMMatrixReadOnly {
  LegacyWindowAlias=WebKitCSSMatrix]
 interface DOMMatrix : DOMMatrixReadOnly {
     [NewObject, Throws] static DOMMatrix fromMatrix(optional DOMMatrixInit other = {});
-    [NewObject, Throws] static DOMMatrixReadOnly fromFloat32Array(Float32Array array32);
-    [NewObject, Throws] static DOMMatrixReadOnly fromFloat64Array(Float64Array array64);
+    [NewObject, Throws] static DOMMatrix fromFloat32Array(Float32Array array32);
+    [NewObject, Throws] static DOMMatrix fromFloat64Array(Float64Array array64);
 
 
     // These attributes are simple aliases for certain elements of the 4x4 matrix

diff --git a/testing/web-platform/tests/css/geometry/DOMMatrix-003.html b/testing/web-platform/tests/css/geometry/DOMMatrix-003.html
@@ -203,6 +203,24 @@
           checkDOMMatrix(result, expected);
         },"test rotateFromVector()");
 
+        test(function() {
+          var result = initialDOMMatrix().rotateFromVector(0, 1);
+          var expected = initialDOMMatrix().rotate(90);
+          checkDOMMatrix(result, expected);
+        },"test rotateFromVector() with x being zero");
+
+        test(function() {
+          var result = initialDOMMatrix().rotateFromVector(1, 0);
+          var expected = initialDOMMatrix()
+          checkDOMMatrix(result, expected);
+        },"test rotateFromVector() with y being zero");
+
+        test(function() {
+          var result = initialDOMMatrix().rotateFromVector(0, 0);
+          var expected = initialDOMMatrix()
+          checkDOMMatrix(result, expected);
+        },"test rotateFromVector() with two zeros");
+
         test(function() {
           var result = initialDOMMatrix().rotateAxisAngle(3, 3, 3, 120);
           var expected = initialDOMMatrix().multiply(getRotationMatrix(3, 3, 3, 120));