1 files changed, 81 insertions, 0 deletions
diff --git a/js/src/jsapi-tests/testStringIsArrayIndex.cpp b/js/src/jsapi-tests/testStringIsArrayIndex.cpp
new file mode 100644
index 0000000000..7eb90fcbac
--- /dev/null
+++ b/js/src/jsapi-tests/testStringIsArrayIndex.cpp
@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <string>
+
+#include "jsfriendapi.h"
+
+#include "jsapi-tests/tests.h"
+
+static const struct TestTuple {
+  /* The string being tested. */
+  const char16_t* string;
+  /* The number of characters from the string to use. */
+  size_t length;
+  /* Whether this string is an index. */
+  bool isindex;
+  /* If it's an index, what index it is.  Ignored if not an index. */
+  uint32_t index;
+
+  constexpr TestTuple(const char16_t* string, bool isindex, uint32_t index)
+      : TestTuple(string, std::char_traits<char16_t>::length(string), isindex,
+                  index) {}
+
+  constexpr TestTuple(const char16_t* string, size_t length, bool isindex,
+                      uint32_t index)
+      : string(string), length(length), isindex(isindex), index(index) {}
+} tests[] = {
+    {u"0", true, 0},
+    {u"1", true, 1},
+    {u"2", true, 2},
+    {u"9", true, 9},
+    {u"10", true, 10},
+    {u"15", true, 15},
+    {u"16", true, 16},
+    {u"17", true, 17},
+    {u"99", true, 99},
+    {u"100", true, 100},
+    {u"255", true, 255},
+    {u"256", true, 256},
+    {u"257", true, 257},
+    {u"999", true, 999},
+    {u"1000", true, 1000},
+    {u"4095", true, 4095},
+    {u"4096", true, 4096},
+    {u"9999", true, 9999},
+    {u"1073741823", true, 1073741823},
+    {u"1073741824", true, 1073741824},
+    {u"1073741825", true, 1073741825},
+    {u"2147483647", true, 2147483647},
+    {u"2147483648", true, 2147483648u},
+    {u"2147483649", true, 2147483649u},
+    {u"4294967294", true, 4294967294u},
+    {u"4294967295", false,
+     0},  // Not an array index because need to be able to represent length
+    {u"-1", false, 0},
+    {u"abc", false, 0},
+    {u" 0", false, 0},
+    {u"0 ", false, 0},
+    // Tests to make sure the passed-in length is taken into account
+    {u"0 ", 1, true, 0},
+    {u"123abc", 3, true, 123},
+    {u"123abc", 2, true, 12},
+};
+
+BEGIN_TEST(testStringIsArrayIndex) {
+  for (const auto& test : tests) {
+    uint32_t index;
+    bool isindex = js::StringIsArrayIndex(test.string, test.length, &index);
+    CHECK_EQUAL(isindex, test.isindex);
+    if (isindex) {
+      CHECK_EQUAL(index, test.index);
+    }
+  }
+
+  return true;
+}
+END_TEST(testStringIsArrayIndex)