test/mjsunit/array-slice.js - v8/v8.git - Git at Google

 // Copyright 2010 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
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 // Flags: --allow-natives-syntax

 // Check that slicing array of holes keeps it as array of holes

 (function() {
   var array = new Array(10);
   for (var i = 0; i < 7; i++) {
     var sliced = array.slice();
     assertEquals(array.length, sliced.length);
     assertFalse(0 in sliced);
   }
 })();


 // Check various variants of empty array's slicing.
 (function() {
   for (var i = 0; i < 7; i++) {
     assertEquals([], [].slice(0, 0));
     assertEquals([], [].slice(1, 0));
     assertEquals([], [].slice(0, 1));
     assertEquals([], [].slice(-1, 0));
   }
 })();


 // Check various forms of arguments omission.
 (function() {
   var array = new Array(7);

   for (var i = 0; i < 7; i++) {
     assertEquals(array, array.slice());
     assertEquals(array, array.slice(0));
     assertEquals(array, array.slice(undefined));
     assertEquals(array, array.slice("foobar"));
     assertEquals(array, array.slice(undefined, undefined));
   }
 })();


 // Check variants of negatives and positive indices.
 (function() {
   var array = new Array(7);

   for (var i = 0; i < 7; i++) {
     assertEquals(7, array.slice(-100).length);
     assertEquals(3, array.slice(-3).length);
     assertEquals(3, array.slice(4).length);
     assertEquals(1, array.slice(6).length);
     assertEquals(0, array.slice(7).length);
     assertEquals(0, array.slice(8).length);
     assertEquals(0, array.slice(100).length);

     assertEquals(0, array.slice(0, -100).length);
     assertEquals(4, array.slice(0, -3).length);
     assertEquals(4, array.slice(0, 4).length);
     assertEquals(6, array.slice(0, 6).length);
     assertEquals(7, array.slice(0, 7).length);
     assertEquals(7, array.slice(0, 8).length);
     assertEquals(7, array.slice(0, 100).length);

     // Some exotic cases.

     obj = { toString: function() { throw 'Exception'; } };

     // More than 2 arguments:
     assertEquals(7, array.slice(0, 7, obj, null, undefined).length);

     // Custom conversion:
     assertEquals(1, array.slice({valueOf: function() { return 1; }},
                                 {toString: function() { return 2; }}).length);

     // Throwing an exception in conversion:
     try {
       assertEquals(7, array.slice(0, obj).length);
       throw 'Should have thrown';
     } catch (e) {
       assertEquals('Exception', e);
     }
   }
 })();


 // Nasty: modify the array in ToInteger.
 (function() {
   var array = [];
   var expected = []
   bad_guy = { valueOf: function() { array.push(array.length); return -1; } };

   for (var i = 0; i < 13; i++) {
     var sliced = array.slice(bad_guy);
     expected.push(i);
     assertEquals(expected, array);
     // According to the spec (15.4.4.10), length is calculated before
     // performing ToInteger on arguments.
     if (i == 0) {
       assertEquals([], sliced);  // Length was 0, nothing to get.
     } else {
       // Actually out of array [0..i] we get [i - 1] as length is i.
       assertEquals([i - 1], sliced);
     }
   }
 })();


 // Now check the case with array of holes and some elements on prototype.
 // Note: that is important that this test runs before the next one
 // as the next one tampers Array.prototype.
 (function() {
   var len = 9;
   var array = new Array(len);

   var at3 = "@3";
   var at7 = "@7";

   for (var i = 0; i < 7; i++) {
     var array_proto = [];
     array_proto[3] = at3;
     array_proto[7] = at7;
     array.__proto__ = array_proto;

     assertEquals(len, array.length);
     for (var i = 0; i < array.length; i++) {
       assertEquals(array[i], array_proto[i]);
     }

     var sliced = array.slice();

     assertEquals(len, sliced.length);

     assertTrue(delete array_proto[3]);
     assertTrue(delete array_proto[7]);

     // Note that slice copies values from prototype into the array.
     assertEquals(array[3], undefined);
     assertFalse(array.hasOwnProperty(3));
     assertEquals(sliced[3], at3);
     assertTrue(sliced.hasOwnProperty(3));

     assertEquals(array[7], undefined);
     assertFalse(array.hasOwnProperty(7));
     assertEquals(sliced[7], at7);
     assertTrue(sliced.hasOwnProperty(7));

     // ... but keeps the rest as holes:
     array_proto[5] = "@5";
     assertEquals(array[5], array_proto[5]);
     assertFalse(array.hasOwnProperty(5));
   }
 })();


 // Now check the case with array of holes and some elements on prototype.
 (function() {
   var len = 9;
   var array = new Array(len);

   var at3 = "@3";
   var at7 = "@7";

   for (var i = 0; i < 7; i++) {
     Array.prototype[3] = at3;
     Array.prototype[7] = at7;

     assertEquals(len, array.length);
     for (var i = 0; i < array.length; i++) {
       assertEquals(array[i], Array.prototype[i]);
     }

     var sliced = array.slice();

     assertEquals(len, sliced.length);

     assertTrue(delete Array.prototype[3]);
     assertTrue(delete Array.prototype[7]);

     // Note that slice copies values from prototype into the array.
     assertEquals(array[3], undefined);
     assertFalse(array.hasOwnProperty(3));
     assertEquals(sliced[3], at3);
     assertTrue(sliced.hasOwnProperty(3));

     assertEquals(array[7], undefined);
     assertFalse(array.hasOwnProperty(7));
     assertEquals(sliced[7], at7);
     assertTrue(sliced.hasOwnProperty(7));

     // ... but keeps the rest as holes:
     Array.prototype[5] = "@5";
     assertEquals(array[5], Array.prototype[5]);
     assertFalse(array.hasOwnProperty(5));
     assertEquals(sliced[5], Array.prototype[5]);
     assertFalse(sliced.hasOwnProperty(5));

     assertTrue(delete Array.prototype[5]);
   }
 })();

 // Check slicing on arguments object.
 (function() {
   function func(expected, a0, a1, a2) {
     let result =  Array.prototype.slice.call(arguments, 1);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
     assertEquals(expected, result);
   }

   func([]);
   func(['a'], 'a');
   func(['a', 1], 'a', 1);
   func(['a', 1, 2, 3, 4, 5], 'a', 1, 2, 3, 4, 5);
   func(['a', 1, undefined], 'a', 1, undefined);
   func(['a', 1, undefined, void(0)], 'a', 1, undefined, void(0));
 })();

 // Check slicing on arguments object when missing arguments get assigined.
 (function() {
   function func(x, y) {
     assertEquals(1, arguments.length);
     assertEquals(undefined, y);
     y = 239;
     assertEquals(1, arguments.length);  // arguments length is the same.
     let result = Array.prototype.slice.call(arguments, 0);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
     assertEquals([x], result);
   }

   func('a');
 })();

 // Check slicing on arguments object when length property has been set.
 (function() {
   function func(x, y) {
     assertEquals(1, arguments.length);
     arguments.length = 7;
     let result = Array.prototype.slice.call(arguments, 0);
     assertEquals([x,,,,,,,], result);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
   }

   func('a');
 })();

 // Check slicing on arguments object when length property has been set to
 // some strange value.
 (function() {
   function func(x, y) {
     assertEquals(1, arguments.length);
     arguments.length = 'foobar';
     let result = Array.prototype.slice.call(arguments, 0);
     assertEquals([], result);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
   }

   func('a');
 })();

 // Check slicing on arguments object when extra argument has been added
 // via indexed assignment.
 (function() {
   function func(x, y) {
     assertEquals(1, arguments.length);
     arguments[3] = 239;
     let result = Array.prototype.slice.call(arguments, 0);
     assertEquals([x], result);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
   }

   func('a');
 })();

 // Check slicing on arguments object when argument has been deleted by index.
 (function() {
   function func(x, y, z) {
     assertEquals(3, arguments.length);
     delete arguments[1];
     let result = Array.prototype.slice.call(arguments, 0);
     assertEquals([x,,z], result);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
   }

   func('a', 'b', 'c');
 })();

 // Check slicing of holey objects with elements in the prototype
 (function() {
   function f() {
     delete arguments[1];
     arguments.__proto__[1] = 5;
     var result = Array.prototype.slice.call(arguments);
     delete arguments.__proto__[1];
     assertEquals([1,5,3], result);
     %HeapObjectVerify(result);
     %HeapObjectVerify(arguments);
   }
   f(1,2,3);
 })();
	// Copyright 2010 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
	// with the distribution.
	// * Neither the name of Google Inc. nor the names of its
	// contributors may be used to endorse or promote products derived
	// from this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	// Flags: --allow-natives-syntax

	// Check that slicing array of holes keeps it as array of holes

	(function() {
	var array = new Array(10);
	for (var i = 0; i < 7; i++) {
	var sliced = array.slice();
	assertEquals(array.length, sliced.length);
	assertFalse(0 in sliced);
	}
	})();


	// Check various variants of empty array's slicing.
	(function() {
	for (var i = 0; i < 7; i++) {
	assertEquals([], [].slice(0, 0));
	assertEquals([], [].slice(1, 0));
	assertEquals([], [].slice(0, 1));
	assertEquals([], [].slice(-1, 0));
	}
	})();


	// Check various forms of arguments omission.
	(function() {
	var array = new Array(7);

	for (var i = 0; i < 7; i++) {
	assertEquals(array, array.slice());
	assertEquals(array, array.slice(0));
	assertEquals(array, array.slice(undefined));
	assertEquals(array, array.slice("foobar"));
	assertEquals(array, array.slice(undefined, undefined));
	}
	})();


	// Check variants of negatives and positive indices.
	(function() {
	var array = new Array(7);

	for (var i = 0; i < 7; i++) {
	assertEquals(7, array.slice(-100).length);
	assertEquals(3, array.slice(-3).length);
	assertEquals(3, array.slice(4).length);
	assertEquals(1, array.slice(6).length);
	assertEquals(0, array.slice(7).length);
	assertEquals(0, array.slice(8).length);
	assertEquals(0, array.slice(100).length);

	assertEquals(0, array.slice(0, -100).length);
	assertEquals(4, array.slice(0, -3).length);
	assertEquals(4, array.slice(0, 4).length);
	assertEquals(6, array.slice(0, 6).length);
	assertEquals(7, array.slice(0, 7).length);
	assertEquals(7, array.slice(0, 8).length);
	assertEquals(7, array.slice(0, 100).length);

	// Some exotic cases.

	obj = { toString: function() { throw 'Exception'; } };

	// More than 2 arguments:
	assertEquals(7, array.slice(0, 7, obj, null, undefined).length);

	// Custom conversion:
	assertEquals(1, array.slice({valueOf: function() { return 1; }},
	{toString: function() { return 2; }}).length);

	// Throwing an exception in conversion:
	try {
	assertEquals(7, array.slice(0, obj).length);
	throw 'Should have thrown';
	} catch (e) {
	assertEquals('Exception', e);
	}
	}
	})();


	// Nasty: modify the array in ToInteger.
	(function() {
	var array = [];
	var expected = []
	bad_guy = { valueOf: function() { array.push(array.length); return -1; } };

	for (var i = 0; i < 13; i++) {
	var sliced = array.slice(bad_guy);
	expected.push(i);
	assertEquals(expected, array);
	// According to the spec (15.4.4.10), length is calculated before
	// performing ToInteger on arguments.
	if (i == 0) {
	assertEquals([], sliced); // Length was 0, nothing to get.
	} else {
	// Actually out of array [0..i] we get [i - 1] as length is i.
	assertEquals([i - 1], sliced);
	}
	}
	})();


	// Now check the case with array of holes and some elements on prototype.
	// Note: that is important that this test runs before the next one
	// as the next one tampers Array.prototype.
	(function() {
	var len = 9;
	var array = new Array(len);

	var at3 = "@3";
	var at7 = "@7";

	for (var i = 0; i < 7; i++) {
	var array_proto = [];
	array_proto[3] = at3;
	array_proto[7] = at7;
	array.__proto__ = array_proto;

	assertEquals(len, array.length);
	for (var i = 0; i < array.length; i++) {
	assertEquals(array[i], array_proto[i]);
	}

	var sliced = array.slice();

	assertEquals(len, sliced.length);

	assertTrue(delete array_proto[3]);
	assertTrue(delete array_proto[7]);

	// Note that slice copies values from prototype into the array.
	assertEquals(array[3], undefined);
	assertFalse(array.hasOwnProperty(3));
	assertEquals(sliced[3], at3);
	assertTrue(sliced.hasOwnProperty(3));

	assertEquals(array[7], undefined);
	assertFalse(array.hasOwnProperty(7));
	assertEquals(sliced[7], at7);
	assertTrue(sliced.hasOwnProperty(7));

	// ... but keeps the rest as holes:
	array_proto[5] = "@5";
	assertEquals(array[5], array_proto[5]);
	assertFalse(array.hasOwnProperty(5));
	}
	})();


	// Now check the case with array of holes and some elements on prototype.
	(function() {
	var len = 9;
	var array = new Array(len);

	var at3 = "@3";
	var at7 = "@7";

	for (var i = 0; i < 7; i++) {
	Array.prototype[3] = at3;
	Array.prototype[7] = at7;

	assertEquals(len, array.length);
	for (var i = 0; i < array.length; i++) {
	assertEquals(array[i], Array.prototype[i]);
	}

	var sliced = array.slice();

	assertEquals(len, sliced.length);

	assertTrue(delete Array.prototype[3]);
	assertTrue(delete Array.prototype[7]);

	// Note that slice copies values from prototype into the array.
	assertEquals(array[3], undefined);
	assertFalse(array.hasOwnProperty(3));
	assertEquals(sliced[3], at3);
	assertTrue(sliced.hasOwnProperty(3));

	assertEquals(array[7], undefined);
	assertFalse(array.hasOwnProperty(7));
	assertEquals(sliced[7], at7);
	assertTrue(sliced.hasOwnProperty(7));

	// ... but keeps the rest as holes:
	Array.prototype[5] = "@5";
	assertEquals(array[5], Array.prototype[5]);
	assertFalse(array.hasOwnProperty(5));
	assertEquals(sliced[5], Array.prototype[5]);
	assertFalse(sliced.hasOwnProperty(5));

	assertTrue(delete Array.prototype[5]);
	}
	})();

	// Check slicing on arguments object.
	(function() {
	function func(expected, a0, a1, a2) {
	let result = Array.prototype.slice.call(arguments, 1);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	assertEquals(expected, result);
	}

	func([]);
	func(['a'], 'a');
	func(['a', 1], 'a', 1);
	func(['a', 1, 2, 3, 4, 5], 'a', 1, 2, 3, 4, 5);
	func(['a', 1, undefined], 'a', 1, undefined);
	func(['a', 1, undefined, void(0)], 'a', 1, undefined, void(0));
	})();

	// Check slicing on arguments object when missing arguments get assigined.
	(function() {
	function func(x, y) {
	assertEquals(1, arguments.length);
	assertEquals(undefined, y);
	y = 239;
	assertEquals(1, arguments.length); // arguments length is the same.
	let result = Array.prototype.slice.call(arguments, 0);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	assertEquals([x], result);
	}

	func('a');
	})();

	// Check slicing on arguments object when length property has been set.
	(function() {
	function func(x, y) {
	assertEquals(1, arguments.length);
	arguments.length = 7;
	let result = Array.prototype.slice.call(arguments, 0);
	assertEquals([x,,,,,,,], result);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	}

	func('a');
	})();

	// Check slicing on arguments object when length property has been set to
	// some strange value.
	(function() {
	function func(x, y) {
	assertEquals(1, arguments.length);
	arguments.length = 'foobar';
	let result = Array.prototype.slice.call(arguments, 0);
	assertEquals([], result);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	}

	func('a');
	})();

	// Check slicing on arguments object when extra argument has been added
	// via indexed assignment.
	(function() {
	function func(x, y) {
	assertEquals(1, arguments.length);
	arguments[3] = 239;
	let result = Array.prototype.slice.call(arguments, 0);
	assertEquals([x], result);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	}

	func('a');
	})();

	// Check slicing on arguments object when argument has been deleted by index.
	(function() {
	function func(x, y, z) {
	assertEquals(3, arguments.length);
	delete arguments[1];
	let result = Array.prototype.slice.call(arguments, 0);
	assertEquals([x,,z], result);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	}

	func('a', 'b', 'c');
	})();

	// Check slicing of holey objects with elements in the prototype
	(function() {
	function f() {
	delete arguments[1];
	arguments.__proto__[1] = 5;
	var result = Array.prototype.slice.call(arguments);
	delete arguments.__proto__[1];
	assertEquals([1,5,3], result);
	%HeapObjectVerify(result);
	%HeapObjectVerify(arguments);
	}
	f(1,2,3);
	})();