Add m-esr52 at 52.6.0

1 files changed, 31 insertions, 0 deletions

diff --git a/js/src/jit-test/tests/basic/error-stack-accessors.js b/js/src/jit-test/tests/basic/error-stack-accessors.js
new file mode 100644
index 000000000..9bbcae14b
--- /dev/null
+++ b/js/src/jit-test/tests/basic/error-stack-accessors.js
@@ -0,0 +1,31 @@
+// Test the Error.prototype.stack getter/setter with various "fun" edge cases.
+
+load(libdir + "asserts.js");
+
+// Stack should be accessible in subclasses. The accessor should walk up the
+// prototype chain.
+assertEq(typeof Object.create(Error()).stack, "string");
+assertEq(Object.create(Error.prototype).stack, "");
+
+// Stack should be overridable in subclasses.
+{
+  let myError = Object.create(Error());
+  myError.stack = 5;
+  assertEq(myError.stack, 5);
+
+  let myOtherError = Object.create(Error.prototype);
+  myOtherError.stack = 2;
+  assertEq(myOtherError.stack, 2);
+}
+
+// Should throw when there is no Error in the `this` object's prototype chain.
+var obj = Object.create(null);
+var desc = Object.getOwnPropertyDescriptor(Error.prototype, "stack");
+Object.defineProperty(obj, "stack", desc);
+assertThrowsInstanceOf(() => obj.stack, TypeError);
+
+// Should throw with non-object `this` values.
+assertThrowsInstanceOf(desc.set,                TypeError);
+assertThrowsInstanceOf(desc.set.bind("string"), TypeError);
+assertThrowsInstanceOf(desc.get,                TypeError);
+assertThrowsInstanceOf(desc.get.bind("string"), TypeError);