1 files changed, 31 insertions, 0 deletions
diff --git a/testing/web-platform/tests/common/arrays.js b/testing/web-platform/tests/common/arrays.js
new file mode 100644
index 0000000000..2b31bb4179
--- /dev/null
+++ b/testing/web-platform/tests/common/arrays.js
@@ -0,0 +1,31 @@
+/**
+ * Callback for checking equality of c and d.
+ *
+ * @callback equalityCallback
+ * @param {*} c
+ * @param {*} d
+ * @returns {boolean}
+ */
+
+/**
+ * Returns true if the given arrays are equal. Optionally can pass an equality function.
+ * @param {Array} a
+ * @param {Array} b
+ * @param {equalityCallback} callbackFunction - defaults to `c === d`
+ * @returns {boolean}
+ */
+export function areArraysEqual(a, b, equalityFunction = (c, d) => { return c === d; }) {
+  try {
+    if (a.length !== b.length)
+      return false;
+
+    for (let i = 0; i < a.length; i++) {
+      if (!equalityFunction(a[i], b[i]))
+        return false;
+    }
+  } catch (ex) {
+    return false;
+  }
+
+  return true;
+}