1 files changed, 96 insertions, 0 deletions
diff --git a/js/src/tests/ecma_6/Function/has-instance-jitted.js b/js/src/tests/ecma_6/Function/has-instance-jitted.js
new file mode 100644
index 000000000..a2d33abc7
--- /dev/null
+++ b/js/src/tests/ecma_6/Function/has-instance-jitted.js
@@ -0,0 +1,96 @@
+const OriginalHasInstance = Function.prototype[Symbol.hasInstance];
+
+// Ensure that folding doesn't impact user defined @@hasInstance methods.
+{
+    function Test() {
+        this.x = 1;
+    }
+
+    Object.defineProperty(Test, Symbol.hasInstance,
+                          {writable: true, value: () => false});
+
+    function x(t) {
+        return t instanceof Test;
+    }
+
+    function y() {
+        let t = new Test;
+        let b = true;
+        for (let i = 0; i < 10; i++) {
+            b = b && x(t);
+        }
+        return b;
+    }
+
+
+    function z() {
+        let f = 0;
+        let t = 0;
+        for (let i = 0; i < 100; i++)
+            assertEq(y(), false);
+    }
+
+    z();
+}
+
+// Ensure that the jitting does not clobber user defined @@hasInstance methods.
+{
+    function a() {
+        function b() {};
+        b.__proto__ = a.prototype;
+        return b;
+    };
+    let c = new a();
+
+    let t = 0;
+    let f = 0;
+    let e = 0;
+    for (let i = 0; i < 40000; i++) {
+        if (i == 20000)
+            Object.defineProperty(a.prototype, Symbol.hasInstance,
+                                  {writable: true, value: () => true});
+        if (i == 30000)
+            Object.setPrototypeOf(c, Function.prototype);
+
+        if (1 instanceof c) {
+            t++;
+        } else {
+            f++;
+        }
+    }
+
+    assertEq(t, 10000);
+    assertEq(f, 30000);
+}
+
+{
+    function a() {};
+    function b() {};
+    Object.defineProperty(a, Symbol.hasInstance, {writable: true, value: () => true});
+    assertEq(b instanceof a, true);
+    for (let _ of Array(10000))
+        assertEq(b instanceof a, true);
+}
+
+{
+    function a(){};
+    function b(){};
+    function c(){};
+    function d(){};
+    function e(){};
+    Object.defineProperty(a, Symbol.hasInstance, {value: () => true });
+    Object.defineProperty(b, Symbol.hasInstance, {value: () => true });
+    Object.defineProperty(c, Symbol.hasInstance, {value: () => true });
+    Object.defineProperty(d, Symbol.hasInstance, {value: () => true });
+    let funcs = [a, b, c, d];
+    for (let f of funcs)
+        assertEq(e instanceof f, true);
+
+    for (let _ of Array(10001)) {
+        for (let f of funcs)
+            assertEq(e instanceof f, true);
+    }
+}
+
+if (typeof reportCompare === "function")
+    reportCompare(true, true);