Fix #13543. offsetWidth is wrong on non-1 zoom. Close gh-1194.

3 files changed, 30 insertions, 24 deletions

diff --git a/src/core.js b/src/core.js
index c0a32762d..66c60774b 100644
--- a/src/core.js
+++ b/src/core.js
@@ -781,7 +781,30 @@ jQuery.extend({
 				length ? fn( elems[0], key ) : emptyGet;
 	},
 
-	now: Date.now
+	now: Date.now,
+
+	// A method for quickly swapping in/out CSS properties to get correct calculations.
+	// Note: this method belongs to the css module but it's needed here for the support module.
+	// If support gets modularized, this method should be moved back to the css module.
+	swap: function( elem, options, callback, args ) {
+		var ret, name,
+			old = {};
+
+		// Remember the old values, and insert the new ones
+		for ( name in options ) {
+			old[ name ] = elem.style[ name ];
+			elem.style[ name ] = options[ name ];
+		}
+
+		ret = callback.apply( elem, args || [] );
+
+		// Revert the old values
+		for ( name in options ) {
+			elem.style[ name ] = old[ name ];
+		}
+
+		return ret;
+	}
 });
 
 jQuery.ready.promise = function( obj ) {
diff --git a/src/css.js b/src/css.js
index 8684dc265..522982b3f 100644
--- a/src/css.js
+++ b/src/css.js
@@ -277,27 +277,6 @@ jQuery.extend({
 			return extra === true || jQuery.isNumeric( num ) ? num || 0 : val;
 		}
 		return val;
-	},
-
-	// A method for quickly swapping in/out CSS properties to get correct calculations
-	swap: function( elem, options, callback, args ) {
-		var ret, name,
-			old = {};
-
-		// Remember the old values, and insert the new ones
-		for ( name in options ) {
-			old[ name ] = elem.style[ name ];
-			elem.style[ name ] = options[ name ];
-		}
-
-		ret = callback.apply( elem, args || [] );
-
-		// Revert the old values
-		for ( name in options ) {
-			elem.style[ name ] = old[ name ];
-		}
-
-		return ret;
 	}
 });
 
diff --git a/src/support.js b/src/support.js
index bc02ee862..b80957a39 100644
--- a/src/support.js
+++ b/src/support.js
@@ -75,12 +75,16 @@ jQuery.support = (function( support ) {
 		container = document.createElement("div");
 		container.style.cssText = "border:0;width:0;height:0;position:absolute;top:0;left:-9999px;margin-top:1px";
 
-		// Check box-sizing and margin behavior
+		// Check box-sizing and margin behavior.
 		body.appendChild( container ).appendChild( div );
 		div.innerHTML = "";
 		div.style.cssText = "box-sizing:border-box;-moz-box-sizing:border-box;-webkit-box-sizing:border-box;padding:1px;border:1px;display:block;width:4px;margin-top:1%;position:absolute;top:1%;";
 
-		support.boxSizing = div.offsetWidth === 4;
+		// Workaround failing boxSizing test due to offsetWidth returning wrong value
+		// with some non-1 values of body zoom, ticket #13543
+		jQuery.swap( body, body.style.zoom != null ? { zoom: 1 } : {}, function() {
+			support.boxSizing = div.offsetWidth === 4;
+		});
 		support.doesNotIncludeMarginInBodyOffset = body.offsetTop !== 1;
 
 		// Use window.getComputedStyle because jsdom on node.js will break without it.