Make `String.prototype.{starts,ends}With` throw when passing a regular expression

test/mjsunit/harmony/string-startswith.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 48 matching lines @@
   msg: "Number 1234.34", val: 1234.34
 }, {
   msg: "Integer number 0", val: 0
 }, {
   msg: "Negative number -1", val: -1
 }, {
   msg: "Boolean true", val: true
 }, {
   msg: "Boolean false", val: false
 }, {
-  msg: "Regular expression /\d+/", val: /\d+/
-}, {
   msg: "Empty array []", val: []
 }, {
   msg: "Empty object {}", val: {}
 }, {
   msg: "Array of size 3", val: new Array(3)
 }];
 
 function testNonStringValues() {
   var i = 0;
   var l = TEST_INPUT.length;
@@ skipping 45 matching lines @@
 assertFalse("abc".startsWith("d", 2));
 assertFalse("abc".startsWith("dcd", 2));
 assertFalse("abc".startsWith("a", 42));
 assertFalse("abc".startsWith("a", Infinity));
 assertTrue("abc".startsWith("a", NaN));
 assertFalse("abc".startsWith("b", NaN));
 assertTrue("abc".startsWith("ab", -43));
 assertTrue("abc".startsWith("ab", -Infinity));
 assertFalse("abc".startsWith("bc", -42));
 assertFalse("abc".startsWith("bc", -Infinity));
+
+// Test cases taken from https://github.com/mathiasbynens/String.prototype.startsWith/blob/master/tests/tests.js
+Object.prototype[1] = 2; // try to break `arguments[1]`
+
+assertEquals(String.prototype.startsWith.length, 1);
+assertEquals(String.prototype.propertyIsEnumerable("startsWith"), false);
+
+assertEquals("undefined".startsWith(), true);
+assertEquals("undefined".startsWith(undefined), true);
+assertEquals("undefined".startsWith(null), false);
+assertEquals("null".startsWith(), false);
+assertEquals("null".startsWith(undefined), false);
+assertEquals("null".startsWith(null), true);
+
+assertEquals("abc".startsWith(), false);
+assertEquals("abc".startsWith(""), true);
+assertEquals("abc".startsWith("\0"), false);
+assertEquals("abc".startsWith("a"), true);
+assertEquals("abc".startsWith("b"), false);
+assertEquals("abc".startsWith("ab"), true);
+assertEquals("abc".startsWith("bc"), false);
+assertEquals("abc".startsWith("abc"), true);
+assertEquals("abc".startsWith("bcd"), false);
+assertEquals("abc".startsWith("abcd"), false);
+assertEquals("abc".startsWith("bcde"), false);
+
+assertEquals("abc".startsWith("", NaN), true);
+assertEquals("abc".startsWith("\0", NaN), false);
+assertEquals("abc".startsWith("a", NaN), true);
+assertEquals("abc".startsWith("b", NaN), false);
+assertEquals("abc".startsWith("ab", NaN), true);
+assertEquals("abc".startsWith("bc", NaN), false);
+assertEquals("abc".startsWith("abc", NaN), true);
+assertEquals("abc".startsWith("bcd", NaN), false);
+assertEquals("abc".startsWith("abcd", NaN), false);
+assertEquals("abc".startsWith("bcde", NaN), false);
+
+assertEquals("abc".startsWith("", false), true);
+assertEquals("abc".startsWith("\0", false), false);
+assertEquals("abc".startsWith("a", false), true);
+assertEquals("abc".startsWith("b", false), false);
+assertEquals("abc".startsWith("ab", false), true);
+assertEquals("abc".startsWith("bc", false), false);
+assertEquals("abc".startsWith("abc", false), true);
+assertEquals("abc".startsWith("bcd", false), false);
+assertEquals("abc".startsWith("abcd", false), false);
+assertEquals("abc".startsWith("bcde", false), false);
+
+assertEquals("abc".startsWith("", undefined), true);
+assertEquals("abc".startsWith("\0", undefined), false);
+assertEquals("abc".startsWith("a", undefined), true);
+assertEquals("abc".startsWith("b", undefined), false);
+assertEquals("abc".startsWith("ab", undefined), true);
+assertEquals("abc".startsWith("bc", undefined), false);
+assertEquals("abc".startsWith("abc", undefined), true);
+assertEquals("abc".startsWith("bcd", undefined), false);
+assertEquals("abc".startsWith("abcd", undefined), false);
+assertEquals("abc".startsWith("bcde", undefined), false);
+
+assertEquals("abc".startsWith("", null), true);
+assertEquals("abc".startsWith("\0", null), false);
+assertEquals("abc".startsWith("a", null), true);
+assertEquals("abc".startsWith("b", null), false);
+assertEquals("abc".startsWith("ab", null), true);
+assertEquals("abc".startsWith("bc", null), false);
+assertEquals("abc".startsWith("abc", null), true);
+assertEquals("abc".startsWith("bcd", null), false);
+assertEquals("abc".startsWith("abcd", null), false);
+assertEquals("abc".startsWith("bcde", null), false);
+
+assertEquals("abc".startsWith("", -Infinity), true);
+assertEquals("abc".startsWith("\0", -Infinity), false);
+assertEquals("abc".startsWith("a", -Infinity), true);
+assertEquals("abc".startsWith("b", -Infinity), false);
+assertEquals("abc".startsWith("ab", -Infinity), true);
+assertEquals("abc".startsWith("bc", -Infinity), false);
+assertEquals("abc".startsWith("abc", -Infinity), true);
+assertEquals("abc".startsWith("bcd", -Infinity), false);
+assertEquals("abc".startsWith("abcd", -Infinity), false);
+assertEquals("abc".startsWith("bcde", -Infinity), false);
+
+assertEquals("abc".startsWith("", -1), true);
+assertEquals("abc".startsWith("\0", -1), false);
+assertEquals("abc".startsWith("a", -1), true);
+assertEquals("abc".startsWith("b", -1), false);
+assertEquals("abc".startsWith("ab", -1), true);
+assertEquals("abc".startsWith("bc", -1), false);
+assertEquals("abc".startsWith("abc", -1), true);
+assertEquals("abc".startsWith("bcd", -1), false);
+assertEquals("abc".startsWith("abcd", -1), false);
+assertEquals("abc".startsWith("bcde", -1), false);
+
+assertEquals("abc".startsWith("", -0), true);
+assertEquals("abc".startsWith("\0", -0), false);
+assertEquals("abc".startsWith("a", -0), true);
+assertEquals("abc".startsWith("b", -0), false);
+assertEquals("abc".startsWith("ab", -0), true);
+assertEquals("abc".startsWith("bc", -0), false);
+assertEquals("abc".startsWith("abc", -0), true);
+assertEquals("abc".startsWith("bcd", -0), false);
+assertEquals("abc".startsWith("abcd", -0), false);
+assertEquals("abc".startsWith("bcde", -0), false);
+
+assertEquals("abc".startsWith("", +0), true);
+assertEquals("abc".startsWith("\0", +0), false);
+assertEquals("abc".startsWith("a", +0), true);
+assertEquals("abc".startsWith("b", +0), false);
+assertEquals("abc".startsWith("ab", +0), true);
+assertEquals("abc".startsWith("bc", +0), false);
+assertEquals("abc".startsWith("abc", +0), true);
+assertEquals("abc".startsWith("bcd", +0), false);
+assertEquals("abc".startsWith("abcd", +0), false);
+assertEquals("abc".startsWith("bcde", +0), false);
+
+assertEquals("abc".startsWith("", 1), true);
+assertEquals("abc".startsWith("\0", 1), false);
+assertEquals("abc".startsWith("a", 1), false);
+assertEquals("abc".startsWith("b", 1), true);
+assertEquals("abc".startsWith("ab", 1), false);
+assertEquals("abc".startsWith("bc", 1), true);
+assertEquals("abc".startsWith("abc", 1), false);
+assertEquals("abc".startsWith("bcd", 1), false);
+assertEquals("abc".startsWith("abcd", 1), false);
+assertEquals("abc".startsWith("bcde", 1), false);
+
+assertEquals("abc".startsWith("", +Infinity), true);
+assertEquals("abc".startsWith("\0", +Infinity), false);
+assertEquals("abc".startsWith("a", +Infinity), false);
+assertEquals("abc".startsWith("b", +Infinity), false);
+assertEquals("abc".startsWith("ab", +Infinity), false);
+assertEquals("abc".startsWith("bc", +Infinity), false);
+assertEquals("abc".startsWith("abc", +Infinity), false);
+assertEquals("abc".startsWith("bcd", +Infinity), false);
+assertEquals("abc".startsWith("abcd", +Infinity), false);
+assertEquals("abc".startsWith("bcde", +Infinity), false);
+
+assertEquals("abc".startsWith("", true), true);
+assertEquals("abc".startsWith("\0", true), false);
+assertEquals("abc".startsWith("a", true), false);
+assertEquals("abc".startsWith("b", true), true);
+assertEquals("abc".startsWith("ab", true), false);
+assertEquals("abc".startsWith("bc", true), true);
+assertEquals("abc".startsWith("abc", true), false);
+assertEquals("abc".startsWith("bcd", true), false);
+assertEquals("abc".startsWith("abcd", true), false);
+assertEquals("abc".startsWith("bcde", true), false);
+
+assertEquals("abc".startsWith("", "x"), true);
+assertEquals("abc".startsWith("\0", "x"), false);
+assertEquals("abc".startsWith("a", "x"), true);
+assertEquals("abc".startsWith("b", "x"), false);
+assertEquals("abc".startsWith("ab", "x"), true);
+assertEquals("abc".startsWith("bc", "x"), false);
+assertEquals("abc".startsWith("abc", "x"), true);
+assertEquals("abc".startsWith("bcd", "x"), false);
+assertEquals("abc".startsWith("abcd", "x"), false);
+assertEquals("abc".startsWith("bcde", "x"), false);
+
+assertEquals("[a-z]+(bar)?".startsWith("[a-z]+"), true);
+assertThrows(function() { "[a-z]+(bar)?".startsWith(/[a-z]+/); }, TypeError);
+assertEquals("[a-z]+(bar)?".startsWith("(bar)?", 6), true);
+assertThrows(function() { "[a-z]+(bar)?".startsWith(/(bar)?/); }, TypeError);
+assertThrows(function() { "[a-z]+/(bar)?/".startsWith(/(bar)?/); }, TypeError);
+
+// http://mathiasbynens.be/notes/javascript-unicode#poo-test
+var string = "I\xF1t\xEBrn\xE2ti\xF4n\xE0liz\xE6ti\xF8n\u2603\uD83D\uDCA9";
+assertEquals(string.startsWith(""), true);
+assertEquals(string.startsWith("\xF1t\xEBr"), false);
+assertEquals(string.startsWith("\xF1t\xEBr", 1), true);
+assertEquals(string.startsWith("\xE0liz\xE6"), false);
+assertEquals(string.startsWith("\xE0liz\xE6", 11), true);
+assertEquals(string.startsWith("\xF8n\u2603\uD83D\uDCA9"), false);
+assertEquals(string.startsWith("\xF8n\u2603\uD83D\uDCA9", 18), true);
+assertEquals(string.startsWith("\u2603"), false);
+assertEquals(string.startsWith("\u2603", 20), true);
+assertEquals(string.startsWith("\uD83D\uDCA9"), false);
+assertEquals(string.startsWith("\uD83D\uDCA9", 21), true);
+
+assertThrows(function() { String.prototype.startsWith.call(undefined); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.call(undefined, "b"); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.call(undefined, "b", 4); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.call(null); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.call(null, "b"); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.call(null, "b", 4); }, TypeError);
+assertEquals(String.prototype.startsWith.call(42, "2"), false);
+assertEquals(String.prototype.startsWith.call(42, "4"), true);
+assertEquals(String.prototype.startsWith.call(42, "b", 4), false);
+assertEquals(String.prototype.startsWith.call(42, "2", 1), true);
+assertEquals(String.prototype.startsWith.call(42, "2", 4), false);
+assertEquals(String.prototype.startsWith.call({ "toString": function() { return "abc"; } }, "b", 0), false);
+assertEquals(String.prototype.startsWith.call({ "toString": function() { return "abc"; } }, "b", 1), true);
+assertEquals(String.prototype.startsWith.call({ "toString": function() { return "abc"; } }, "b", 2), false);
+assertThrows(function() { String.prototype.startsWith.call({ "toString": function() { throw RangeError(); } }, /./); }, RangeError);
+assertThrows(function() { String.prototype.startsWith.call({ "toString": function() { return "abc"; } }, /./); }, TypeError);
+
+assertThrows(function() { String.prototype.startsWith.apply(undefined); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.apply(undefined, ["b"]); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.apply(undefined, ["b", 4]); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.apply(null); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.apply(null, ["b"]); }, TypeError);
+assertThrows(function() { String.prototype.startsWith.apply(null, ["b", 4]); }, TypeError);
+assertEquals(String.prototype.startsWith.apply(42, ["2"]), false);
+assertEquals(String.prototype.startsWith.apply(42, ["4"]), true);
+assertEquals(String.prototype.startsWith.apply(42, ["b", 4]), false);
+assertEquals(String.prototype.startsWith.apply(42, ["2", 1]), true);
+assertEquals(String.prototype.startsWith.apply(42, ["2", 4]), false);
+assertEquals(String.prototype.startsWith.apply({ "toString": function() { return "abc"; } }, ["b", 0]), false);
+assertEquals(String.prototype.startsWith.apply({ "toString": function() { return "abc"; } }, ["b", 1]), true);
+assertEquals(String.prototype.startsWith.apply({ "toString": function() { return "abc"; } }, ["b", 2]), false);
+assertThrows(function() { String.prototype.startsWith.apply({ "toString": function() { throw RangeError(); } }, [/./]); }, RangeError);
+assertThrows(function() { String.prototype.startsWith.apply({ "toString": function() { return "abc"; } }, [/./]); }, TypeError);