Position: Add unit tests for bug 8710

Ref #8710
Closes jquerygh-1071

Author: meyertee

tests/unit/position/position.html

@@ -47,6 +47,9 @@
 	<div id="bug-5280" style="height: 30px; width: 201px;">
 		<div style="width: 50px; height: 10px;"></div>
 	</div>
+
+	<div id="bug-8710-within-smaller" style="position: absolute; width: 100px; height: 99px; top: 0px; left: 0px; line-height: 99px;"></div>
+	<div id="bug-8710-within-bigger" style="position: absolute; width: 100px; height: 101px; top: 0px; left: 0px; line-height: 101px;"></div>
 </div>
 
 </body>

tests/unit/position/position_core.js

@@ -726,4 +726,41 @@ test( "bug #5280: consistent results (avoid fractional values)", function() {
 	deepEqual( offset1, offset2 );
 });
 
+test( "bug #8710: flip if flipped position fits more", function() {
+	expect( 3 );
+
+	// Positions a 10px tall element within 99px height at top 90px.
+	collisionTest({
+		within: "#bug-8710-within-smaller",
+		of: "#parentx",
+		collision: "flip",
+		at: "right bottom+30"
+	}, {
+		top: 0,
+		left: 60
+	}, "flip - top fits all" );
+
+	// Positions a 10px tall element within 99px height at top 92px.
+	collisionTest({
+		within: "#bug-8710-within-smaller",
+		of: "#parentx",
+		collision: "flip",
+		at: "right bottom+32"
+	}, {
+		top: -2,
+		left: 60
+	}, "flip - top fits more" );
+
+	// Positions a 10px tall element within 101px height at top 92px.
+	collisionTest({
+		within: "#bug-8710-within-bigger",
+		of: "#parentx",
+		collision: "flip",
+		at: "right bottom+32"
+	}, {
+		top: 92,
+		left: 60
+	}, "no flip - top fits less" );
+});
+
 }( jQuery ) );