Add WPT test for invalidating WebIDL iterators during forEach

servo · Nov 26, 2019 · 38a666742fbfcd5b392d8644622af890c0ff25cd · 38a6667
1 parent d233558
commit 38a666742fbfcd5b392d8644622af890c0ff25cd
Unified Split

Showing with 50 additions and 0 deletions.

+10 −0 tests/wpt/metadata/MANIFEST.json

+40 −0 tests/wpt/web-platform-tests/WebIDL/ecmascript-binding/iterator-invalidation-foreach.html
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json

      {}
     ]
    ],
+   "WebIDL/ecmascript-binding/iterator-invalidation-foreach.html": [
+    [
+     "WebIDL/ecmascript-binding/iterator-invalidation-foreach.html",
+     {}
+    ]
+   ],
    "WebIDL/ecmascript-binding/iterator-prototype-object.html": [
     [
      "WebIDL/ecmascript-binding/iterator-prototype-object.html",

    "03ada7aa0d4d43811652fc679a00a41b9653013d",
    "testharness"
   ],
+  "WebIDL/ecmascript-binding/iterator-invalidation-foreach.html": [
+   "d6498c3e388e0c637830fa080cca78b0ab0e5305",
+   "testharness"
+  ],
   "WebIDL/ecmascript-binding/iterator-prototype-object.html": [
    "5a935fa20135d88a7268b872b68ab7fe548ab5c7",
    "testharness"
diff --git a/tests/wpt/web-platform-tests/WebIDL/ecmascript-binding/iterator-invalidation-foreach.html b/tests/wpt/web-platform-tests/WebIDL/ecmascript-binding/iterator-invalidation-foreach.html
@@ -0,0 +1,40 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Behavior of iterators when modified within foreach</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<link rel="help" href="https://heycam.github.io/webidl/#es-forEach">
+<link rel="author" title="Manish Goregaokar" href="mailto:manishsmail@gmail.com">
+<script>
+test(function() {
+    let params = new URLSearchParams("a=1&b=2&c=3");
+    let arr = [];
+    params.forEach((p) => {
+        arr.push(p);
+        params.delete("b");
+    })
+    assert_array_equals(arr, ["1", "3"]);
+}, "forEach will not iterate over elements removed during iteration");
+test(function() {
+    let params = new URLSearchParams("a=1&b=2&c=3&d=4");
+    let arr = [];
+    params.forEach((p) => {
+        arr.push(p);
+        if (p == "2") {
+            params.delete("a");
+        }
+    })
+    assert_array_equals(arr, ["1", "2", "4"]);
+}, "Removing elements already iterated over during forEach will cause iterator to skip an element");
+test(function() {
+    let params = new URLSearchParams("a=1&b=2&c=3&d=4");
+    let arr = [];
+    params.forEach((p) => {
+        arr.push(p);
+        if (p == "2") {
+            params.append("e", "5");
+        }
+    })
+    assert_array_equals(arr, ["1", "2", "3", "4", "5"]);
+}, "Elements added during iteration with forEach will be reached");
+</script>