1 files changed, 88 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/cacheir/string-codePointAt-rope-twobyte.js b/js/src/jit-test/tests/cacheir/string-codePointAt-rope-twobyte.js
new file mode 100644
index 0000000000..adbc9995c1
--- /dev/null
+++ b/js/src/jit-test/tests/cacheir/string-codePointAt-rope-twobyte.js
@@ -0,0 +1,88 @@
+function makeString(from) {
+  var codePoints = [];
+  for (var i = 0; i < 16; ++i) {
+    codePoints.push(from + i);
+  }
+  return String.fromCodePoint(...codePoints);
+}
+
+function makeRope() {
+  var left = newRope(makeString(0x140), makeString(0x140 + 16));
+  var right = newRope(makeString(0x160), makeString(0x160 + 16));
+  var rope = newRope(left, right);
+  return {left, right, rope};
+}
+
+// Load a character from the left rope child using a constant index. The input
+// to String.prototype.codePointAt is always rope.
+function testLeftChildConstant() {
+  for (var i = 0; i < 200; ++i) {
+    var {rope} = makeRope();
+
+    var ch = rope.codePointAt(0);
+    assertEq(ch, 0x140);
+  }
+}
+for (var i = 0; i < 2; ++i) {
+  testLeftChildConstant();
+}
+
+// Load a character from the right rope child using a constant index. The input
+// to String.prototype.codePointAt is always rope.
+function testRightChildConstant() {
+  for (var i = 0; i < 200; ++i) {
+    var {rope} = makeRope();
+
+    var ch = rope.codePointAt(32);
+    assertEq(ch, 0x160);
+  }
+}
+for (var i = 0; i < 2; ++i) {
+  testRightChildConstant();
+}
+
+// Load a character from the left rope child using a variable index. The input
+// to String.prototype.codePointAt is always rope.
+function testLeftChildVariable() {
+  for (var i = 0; i < 200; ++i) {
+    var {left, rope} = makeRope();
+
+    var idx = i % left.length;
+    var ch = rope.codePointAt(idx);
+    assertEq(ch, 0x140 + idx);
+  }
+}
+for (var i = 0; i < 2; ++i) {
+  testLeftChildVariable();
+}
+
+// Load a character from the right rope child using a variable index. The input
+// to String.prototype.codePointAt is always rope.
+function testRightChildVariable() {
+  for (var i = 0; i < 200; ++i) {
+    var {left, right, rope} = makeRope();
+
+    var idx = i % right.length;
+    var ch = rope.codePointAt(left.length + idx);
+    assertEq(ch, 0x160 + idx);
+  }
+}
+for (var i = 0; i < 2; ++i) {
+  testRightChildVariable();
+}
+
+// Load all characters from both child ropes. This covers the case when the
+// call to String.prototype.codePointAt linearizes the rope. 
+function testBothChildren() {
+  for (var i = 0; i < 200; ++i) {
+    var {rope} = makeRope();
+
+    for (var j = 0; j < rope.length; ++j) {
+      var ch = rope.codePointAt(j);
+      assertEq(ch, 0x140 + j);
+    }
+  }
+}
+for (var i = 0; i < 2; ++i) {
+  testBothChildren();
+}