1 files changed, 20 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/cacheir/rope-char-at.js b/js/src/jit-test/tests/cacheir/rope-char-at.js
new file mode 100644
index 0000000000..f952f0dd18
--- /dev/null
+++ b/js/src/jit-test/tests/cacheir/rope-char-at.js
@@ -0,0 +1,20 @@
+function test(a, b, firstCharCode) {
+  var s = newRope(a, b);
+  for (var i = 0; i < s.length; i++) {
+    assertEq(s.charCodeAt(i), firstCharCode + i);
+    assertEq(s.charAt(i), String.fromCharCode(firstCharCode + i));
+  }
+  // charAt/charCodeAt support one-level deep ropes without linearizing.
+  assertEq(isRope(s), true);
+  assertEq(isRope(a), false);
+  assertEq(isRope(b), false);
+}
+test("abcdef", "ghijk", 97);
+test("a", "bcdefg", 97);
+test("abcde", "f", 97);
+test("0123456", "7", 48);
+test("\u00fe\u00ff", "\u0100\u0101", 0xfe);
+test("\u1000\u1001\u1002", "\u1003\u1004", 4096);
+
+// charAt/charCodeAt stubs currently fail for nested ropes.
+test("abcdef", newRope("ghij", "klmn"), 97);