[Refactor] increase coverage; remove redundant branches

.eslintrc

@@ -23,7 +23,8 @@
 			"number": false,
 			"string": true
 		}],
-		"no-restricted-syntax": [2, "BreakStatement", "ContinueStatement", "DebuggerStatement", "LabeledStatement", "WithStatement"]
+		"no-restricted-syntax": [2, "BreakStatement", "ContinueStatement", "DebuggerStatement", "LabeledStatement", "WithStatement"],
+		"operator-linebreak": [2, "before"],
 	},
 
 	"overrides": [

test/why.js

@@ -664,6 +664,19 @@ test('functions', function (t) {
 			st.equal(isEqualWhy(fn, copyFunction(fn)), '', inspect(fn) + ' is equal to copyFunction(fn)');
 		});
 
+		var arrow1 = Function('return (a) => {}');
+		var arrow2 = Function('return (b) => {}');
+		st.equal(
+			isEqualWhy(arrow1(), arrow2()),
+			'Function string representations differ',
+			'same name/length arrow functions with different source are not equal'
+		);
+		st.equal(
+			isEqualWhy(arrow1(), arrow1()),
+			'',
+			'same name/length arrow functions with same source are equal'
+		);
+
 		st.end();
 	});
 

why.js

@@ -178,12 +178,18 @@ module.exports = function whyNotEqual(value, other) {
 
 		var valueStr = normalizeFnWhitespace(String(value));
 		var otherStr = normalizeFnWhitespace(String(other));
-		if (whyNotEqual(valueStr, otherStr) === '') { return ''; }
-
-		if (!valueIsGen && !valueIsArrow) {
-			return whyNotEqual(valueStr.replace(/\)\s*\{/, '){'), otherStr.replace(/\)\s*\{/, '){')) === '' ? '' : 'Function string representations differ';
+		if (
+			whyNotEqual(valueStr, otherStr) === ''
+			|| (
+				!valueIsGen
+				&& !valueIsArrow
+				&& whyNotEqual(valueStr.replace(/\)\s*\{/, '){'), otherStr.replace(/\)\s*\{/, '){')) === ''
+			)
+		) {
+			return '';
 		}
-		return whyNotEqual(valueStr, otherStr) === '' ? '' : 'Function string representations differ';
+
+		return 'Function string representations differ';
 	}
 
 	if (typeof value === 'object' || typeof other === 'object') {