Bug 1269174: Fix nsSVGViewBox::HasRect() to return false instead of using stale mBaseVal. r=longsonr

MozReview-Commit-ID: esNxaomT3D

dom/svg/nsSVGViewBox.cpp

@@ -70,6 +70,23 @@ nsSVGViewBox::Init()
   mAnimVal = nullptr;
 }
 
+bool
+nsSVGViewBox::HasRect() const
+{
+  // Check mAnimVal if we have one; otherwise, check mBaseVal if we have one;
+  // otherwise, just return false (we clearly do not have a rect).
+  const nsSVGViewBoxRect* rect = mAnimVal;
+  if (!rect) {
+    if (!mHasBaseVal) {
+      // no anim val, no base val --> no viewbox rect
+      return false;
+    }
+    rect = &mBaseVal;
+  }
+
+  return !rect->none && rect->width >= 0 && rect->height >= 0;
+}
+
 void
 nsSVGViewBox::SetAnimValue(const nsSVGViewBoxRect& aRect,
                            nsSVGElement *aSVGElement)

dom/svg/nsSVGViewBox.h

@@ -52,11 +52,7 @@ public:
    * string, or if any of the four rect values were too big to store in a
    * float, or the width/height are negative.
    */
-  bool HasRect() const
-    {
-      const nsSVGViewBoxRect& rect = GetAnimValue();
-      return !rect.none && rect.width >= 0 && rect.height >= 0;
-    }
+  bool HasRect() const;
 
   /**
    * Returns true if the corresponding "viewBox" attribute either defined a

layout/reftests/svg/dynamic-viewBox-change-01.svg

@@ -0,0 +1,24 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait"
+     id="target" viewBox="-50 -50 20 20"
+     preserveAspectRatio="none">
+  <script>
+  function doTest() {
+    var target = document.getElementById("target");
+    target.removeAttribute("viewBox");
+    document.documentElement.removeAttribute("class");
+  }
+
+  document.addEventListener("MozReftestInvalidate", doTest, false);
+  </script>
+
+  <!-- Lime background to match pass.svg -->
+  <rect height="100%" width="100%" fill="lime"/>
+
+  <!-- Offscreen red rect - the initial |viewBox| makes this visible,
+       but it shouldn't be visible after we remove that attribute: -->
+  <rect x="-50" y="-50" width="20" height="20" fill="red"/>
+</svg>

layout/reftests/svg/dynamic-viewBox-change-02.svg

@@ -0,0 +1,24 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait"
+     id="target" viewBox="-50 -50 20 20"
+     preserveAspectRatio="none">
+  <script>
+  function doTest() {
+    var target = document.getElementById("target");
+    target.setAttribute("viewBox", "");
+    document.documentElement.removeAttribute("class");
+  }
+
+  document.addEventListener("MozReftestInvalidate", doTest, false);
+  </script>
+
+  <!-- Lime background to match pass.svg -->
+  <rect height="100%" width="100%" fill="lime"/>
+
+  <!-- Offscreen red rect - the initial |viewBox| makes this visible,
+       but it shouldn't be visible after we clear that attribute: -->
+  <rect x="-50" y="-50" width="20" height="20" fill="red"/>
+</svg>

layout/reftests/svg/dynamic-viewBox-change-03.svg

@@ -0,0 +1,24 @@
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait"
+     id="target" viewBox="-50 -50 20 20"
+     preserveAspectRatio="none">
+  <script>
+  function doTest() {
+    var target = document.getElementById("target");
+    target.setAttribute("viewBox", "bogus value");
+    document.documentElement.removeAttribute("class");
+  }
+
+  document.addEventListener("MozReftestInvalidate", doTest, false);
+  </script>
+
+  <!-- Lime background to match pass.svg -->
+  <rect height="100%" width="100%" fill="lime"/>
+
+  <!-- Offscreen red rect - the initial |viewBox| makes this visible,
+       but it shouldn't be visible after we tweak that attribute: -->
+  <rect x="-50" y="-50" width="20" height="20" fill="red"/>
+</svg>

layout/reftests/svg/reftest.list

@@ -135,6 +135,9 @@ random-if(/^Windows\x20NT\x205\.1/.test(http.oscpu)) fuzzy-if(/^Windows\x20NT\x2
 random == dynamic-use-nested-01a.svg dynamic-use-nested-01-ref.svg
 random == dynamic-use-nested-01b.svg dynamic-use-nested-01-ref.svg
 == dynamic-use-remove-width.svg dynamic-use-remove-width-ref.svg
+== dynamic-viewBox-change-01.svg pass.svg
+== dynamic-viewBox-change-02.svg pass.svg
+== dynamic-viewBox-change-03.svg pass.svg
 == fragmentIdentifier-01.xhtml pass.svg
 == linked-filter-01.svg pass.svg
 == linked-pattern-01.svg pass.svg