Add m-esr52 at 52.6.0

1 files changed, 26 insertions, 0 deletions

diff --git a/js/src/jit-test/tests/proxy/testDirectProxyDefinePropertyFailure.js b/js/src/jit-test/tests/proxy/testDirectProxyDefinePropertyFailure.js
new file mode 100644
index 000000000..0de3000c3
--- /dev/null
+++ b/js/src/jit-test/tests/proxy/testDirectProxyDefinePropertyFailure.js
@@ -0,0 +1,26 @@
+// Test handling of false return from a handler.defineProperty() hook.
+
+load(libdir + "asserts.js");
+
+var obj = {x: 1, y: 2};
+var nope = false;
+var p = new Proxy(obj, {
+    defineProperty(target, key, desc) { return nope; }
+});
+
+// Object.defineProperty throws on failure.
+print(1);
+assertThrowsInstanceOf(() => Object.defineProperty(p, "z", {value: 3}), TypeError);
+assertEq("z" in obj, false);
+assertThrowsInstanceOf(() => Object.defineProperty(p, "x", {value: 0}), TypeError);
+
+// Setting a property ultimately causes [[DefineOwnProperty]] to be called.
+// In strict mode code only, this is a TypeError.
+print(2);
+assertEq(p.z = 3, 3);
+assertThrowsInstanceOf(() => { "use strict"; p.z = 3; }, TypeError);
+
+// Other falsy values also trigger failure.
+print(3);
+for (nope of [0, -0, NaN, ""])
+    assertThrowsInstanceOf(() => { "use strict"; p.z = 3; }, TypeError);