Add m-esr52 at 52.6.0

1 files changed, 46 insertions, 0 deletions

diff --git a/js/src/tests/ecma_6/Class/superPropDelete.js b/js/src/tests/ecma_6/Class/superPropDelete.js
new file mode 100644
index 000000000..44bf0d3f6
--- /dev/null
+++ b/js/src/tests/ecma_6/Class/superPropDelete.js
@@ -0,0 +1,46 @@
+// Make sure we get the proper side effects.
+// |delete super.prop| and |delete super[expr]| throw universally.
+
+class base {
+    constructor() { }
+}
+
+class derived extends base {
+    constructor() { super(); }
+    testDeleteProp() { delete super.prop; }
+    testDeleteElem() {
+        let sideEffect = 0;
+        assertThrowsInstanceOf(() => delete super[sideEffect = 1], ReferenceError);
+        assertEq(sideEffect, 1);
+    }
+    testDeleteElemPropValFirst() {
+        // The deletion error is a reference error, but by munging the prototype
+        // chain, we can force a typeerror from JSOP_SUPERBASE
+        delete super[Object.setPrototypeOf(derived.prototype, null)];
+    }
+}
+
+var d = new derived();
+assertThrowsInstanceOf(() => d.testDeleteProp(), ReferenceError);
+d.testDeleteElem();
+assertThrowsInstanceOf(() => d.testDeleteElemPropValFirst(), TypeError);
+
+// |delete super.x| does not delete anything before throwing.
+var thing1 = {
+    go() { delete super.toString; }
+};
+let saved = Object.prototype.toString;
+assertThrowsInstanceOf(() => thing1.go(), ReferenceError);
+assertEq(Object.prototype.toString, saved);
+
+// |delete super.x| does not tell the prototype to delete anything, when it's a proxy.
+var thing2 = {
+    go() { delete super.prop; }
+};
+Object.setPrototypeOf(thing2, new Proxy({}, {
+    deleteProperty(x) { throw "FAIL"; }
+}));
+assertThrowsInstanceOf(() => thing2.go(), ReferenceError);
+
+if (typeof reportCompare === 'function')
+    reportCompare(0,0,"OK");