Initial assert helpers

test/harness/assert.js

@@ -0,0 +1,42 @@
+function assert(mustBeTrue, message) {
+    if (mustBeTrue === true) {
+        return;
+    }
+
+    if (message === undefined) {
+        message = 'Expected true but got ' + String(truthy);
+    }
+    $ERROR(message);
+}
+
+assert._isSameValue = function (a, b) {
+    if (a === b) {
+        // Handle +/-0 vs. -/+0
+        return a !== 0 || 1 / a === 1 / b;
+    }
+
+    // Handle NaN vs. NaN
+    return a !== a && b !== b;
+};
+
+assert.sameValue = function (actual, expected, message) {
+    if (assert._isSameValue(actual, expected)) {
+        return;
+    }
+
+    if (message === undefined) {
+        message = 'Expected SameValue(' + String(actual) + ', ' + String(expected) + ') to be true';
+    }
+    $ERROR(message);
+};
+
+assert.notSameValue = function (actual, unexpected, message) {
+    if (!assert._isSameValue(actual, unexpected)) {
+        return;
+    }
+
+    if (message === undefined) {
+        message = 'Expected SameValue(' + String(actual) + ', ' + String(unexpected) + ') to be false';
+    }
+    $ERROR(message);
+};

test/suite/es6/Array.prototype.find/Array.prototype.find_this-defined.js

@@ -8,10 +8,6 @@ description: thisArg should be bound to this if provided
 var globalThis = this;
 
 [1].find(function () {
-    if (this !== Array) {
-      $ERROR('#1: this !== Array');
-    }
-    if (this === globalThis) {
-      $ERROR('#2: this === globalThis. Should be Array');
-    }
+    assert.sameValue(this, Array, 'this should equal Array');
+    assert.notSameValue(this, globalThis, 'this should not equal globalThis');
 }, Array);