join classlist instead of using toString -> removes insignificant whi…

…tespace, do not create hashes for empty class attributes.
fbuchinger · Mar 23, 2017 · 581f2e3 · 581f2e3
1 parent 9c01d04
commit 581f2e3
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Showing 2 changed files with 10 additions and 2 deletions.
diff --git a/src/layoutstats.js b/src/layoutstats.js
@@ -394,8 +394,12 @@ LayoutStats.addMetric({
 			}
 			return hash >>> 0;
 		}
-		// return css classlist as a hash to decrease the size of the JSON metric
-		return {key: hash(node.classList.toString().trim()).toString(36), value: 1};
+
+		var cssClassList = Array.prototype.join.call(node.classList," ");
+		// return css classlist as a hash to decrease the size of the JSON payload
+		if (cssClassList.length > 0) {
+			return {key: hash(cssClassList).toString(36), value: 1};
+		}
 	},
 	reduce: ['uniquekeylist']
 });

diff --git a/test/spec/layoutstats.nodemetrics.js b/test/spec/layoutstats.nodemetrics.js
@@ -22,6 +22,10 @@
 	QUnit.test("measures the css class attributes used by child nodes. It ", function (assert) {
 		var ls = injectAndGetLayoutStats('<div class="foo1 foo2 foo3"></div><span class="foo1 foo2 foo3"></span><div class="bar1 bar2 bar2"></div>');
 		assert.deepEqual(ls.nodeUsedCSSClassAttributesList.sort(),["1bd623p", "c8zwxf"].sort(),"creates an array of unique hashed class list combinations");
+		var ls = injectAndGetLayoutStats('<div class="foo1 foo2 foo3"></div><span class="foo1    foo2 			foo3"></span>');
+		assert.deepEqual(ls.nodeUsedCSSClassAttributesList.sort(),["c8zwxf"],"ignores insignificant whitespace between the classnames when building the hash");
+		var ls = injectAndGetLayoutStats('<div class="     "></div><span class=""></span>');
+		assert.deepEqual(ls.nodeUsedCSSClassAttributesList.sort(),[],"ignores empty class attributes");
 	});
 
 })( window, QUnit );