1 files changed, 129 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/cacheir/new-with-non-object-prototype.js b/js/src/jit-test/tests/cacheir/new-with-non-object-prototype.js
new file mode 100644
index 0000000000..5e146db4b5
--- /dev/null
+++ b/js/src/jit-test/tests/cacheir/new-with-non-object-prototype.js
@@ -0,0 +1,129 @@
+// Test constructing a function when the |.prototype| property isn't an object.
+
+function test(proto) {
+  function Klass() {
+    this.prop = 1;
+  }
+  Klass.prototype = proto;
+
+  const N = 100;
+
+  let c = 0;
+  for (let i = 0; i < N; ++i) {
+    // Create a new object.
+    let o = new Klass();
+
+    // Read a property from the new object to ensure it was correctly allocated
+    // and initialised.
+    c += o.prop;
+
+    // The prototype defaults to %Object.prototype% when the |.prototype|
+    // property isn't an object.
+    assertEq(Object.getPrototypeOf(o), Object.prototype);
+  }
+
+  assertEq(c, N);
+}
+
+const primitivesTypes = [
+  undefined,
+  null,
+  123,
+  true,
+  "str",
+  Symbol(),
+  123n,
+];
+
+for (let primitive of primitivesTypes) {
+  // Create a fresh function object to avoid type pollution.
+  let fn = Function(`return ${test}`)();
+
+  fn(primitive);
+}
+
+// Repeat the test from above, but this time |Klass| is a cross-realm function.
+
+function testCrossRealm(proto) {
+  const otherGlobal = newGlobal();
+  const Klass = otherGlobal.eval(`
+    function Klass() {
+      this.prop = 1;
+    }
+    Klass;
+  `);
+  Klass.prototype = proto;
+
+  const N = 100;
+
+  let c = 0;
+  for (let i = 0; i < N; ++i) {
+    // Create a new object.
+    let o = new Klass();
+
+    // Read a property from the new object to ensure it was correctly allocated
+    // and initialised.
+    c += o.prop;
+
+    // The prototype defaults to %Object.prototype% when the |.prototype|
+    // property isn't an object.
+    assertEq(Object.getPrototypeOf(o), otherGlobal.Object.prototype);
+  }
+
+  assertEq(c, N);
+}
+
+for (let primitive of primitivesTypes) {
+  // Create a fresh function object to avoid type pollution.
+  let fn = Function(`return ${testCrossRealm}`)();
+
+  fn(primitive);
+}
+
+// Repeat the test from above, but this time |Klass| is a cross-realm new.target.
+
+function testCrossRealmNewTarget(proto) {
+  const otherGlobal = newGlobal();
+  const Klass = otherGlobal.eval(`
+    function Klass() {}
+    Klass;
+  `);
+  Klass.prototype = proto;
+
+  class C {
+    constructor() {
+      this.prop = 1;
+    }
+  }
+
+  class D extends C {
+    constructor() {
+      super();
+    }
+  }
+
+  const N = 100;
+
+  let c = 0;
+  for (let i = 0; i < N; ++i) {
+    // Create a new object.
+    let o = Reflect.construct(D, [], Klass);
+
+    // Read a property from the new object to ensure it was correctly allocated
+    // and initialised.
+    c += o.prop;
+
+    // The prototype defaults to %Object.prototype% when the |.prototype|
+    // property isn't an object.
+    assertEq(Object.getPrototypeOf(o), otherGlobal.Object.prototype);
+  }
+
+  assertEq(c, N);
+}
+
+for (let primitive of primitivesTypes) {
+  // Create a fresh function object to avoid type pollution.
+  let fn = Function(`return ${testCrossRealmNewTarget}`)();
+
+  fn(primitive);
+}