Fix ellipse tests in SVGGraphicsElement.getBBox-03.html

Specifying a negative value for rx or ry would result in it taking the other value ry=rx or rx=ry so we need to use 0 to ensure we get a degenerate ellipse.

Differential Revision: https://phabricator.services.mozilla.com/D294700

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=2032517
gecko-commit: fa4459c8d78755629126278d27d6e4549d9af61b
gecko-commit-git: e2bba9b9b4394fbf0fb2c13d70d6880a9771ba4e
gecko-reviewers: dholbert

Author: longsonr

svg/types/scripted/SVGGraphicsElement.getBBox-03.html

@@ -6,11 +6,19 @@
 <link rel="help" href="https://w3c.github.io/svgwg/svg2-draft/types.html#__svg__SVGGraphicsElement__getBBox">
 <link rel="help" href="https://w3c.github.io/svgwg/svg2-draft/coords.html#BoundingBoxes">
 <svg>
+  <!-- negative values are errors, auto will be substituted, which for width,
+       height and r is 0 -->
   <rect id="rect1" x="1" y="2" width="-10" height="20"/>
   <rect id="rect2" x="1" y="2" width="10" height="-20"/>
   <circle id="circle" cx="1" cy="2" r="-10"/>
+  <!-- specifying a negative value for rx or ry is invalid so the other valid
+       radius will be substituted only 0 will produce a degenerate ellipse -->
   <ellipse id="ellipse1" cx="1" cy="12" rx="-5" ry="10"/>
   <ellipse id="ellipse2" cx="6" cy="2" rx="5" ry="-10"/>
+  <circle id="ellipse1-ref" cx="1" cy="12" r="10"/>
+  <circle id="ellipse2-ref" cx="6" cy="2" r="5"/>
+  <ellipse id="ellipse3" cx="1" cy="12" rx="0" ry="10"/>
+  <ellipse id="ellipse4" cx="6" cy="2" rx="5" ry="0"/>
   <image id="image1" x="1" y="2" width="-10" height="20" href="/images/green-100x50.png"/>
   <image id="image2" x="1" y="2" width="10" height="-20" href="/images/green-100x50.png"/>
   <image id="image3" x="1" y="2" width="-10" height="20"/>
@@ -20,24 +28,35 @@
 </svg>
 <script>
 function assertBBox(id, x, y, width, height) {
-  var bbox = document.getElementById(id).getBBox();
+  let bbox = document.getElementById(id).getBBox();
   assert_equals(bbox.x, x, id + ': x');
   assert_equals(bbox.y, y, id + ': y');
   assert_equals(bbox.width, width, id + ': width');
   assert_equals(bbox.height, height, id + ': height');
 }
 
+function assertSameBBox(id1, id2) {
+  let bbox = document.getElementById(id2).getBBox();
+  assertBBox(id1, bbox.x, bbox.y, bbox.width, bbox.height);
+}
+
 function testBBox(id, x, y, width, height) {
   test(() => { assertBBox(id, x, y, width, height) }, id);
 }
 
+function testSameBBox(id1, id2) {
+  test(() => { assertSameBBox(id1, id2) }, id1);
+}
+
 // Per resolution (issue #1018): if a shape is not rendered (negative or
 // zero dimension), getBBox returns (0, 0, 0, 0).
 testBBox('rect1', 0, 0, 0, 0);
 testBBox('rect2', 0, 0, 0, 0);
 testBBox('circle', 0, 0, 0, 0);
-testBBox('ellipse1', 0, 0, 0, 0);
-testBBox('ellipse2', 0, 0, 0, 0);
+testSameBBox('ellipse1', 'ellipse1-ref');
+testSameBBox('ellipse2', 'ellipse2-ref');
+testBBox('ellipse3', 0, 0, 0, 0);
+testBBox('ellipse4', 0, 0, 0, 0);
 testBBox('image3', 0, 0, 0, 0);
 testBBox('image4', 0, 0, 0, 0);
 testBBox('foreign1', 0, 0, 0, 0);