Home | History | Annotate | Download | only in mjsunit 
      1 // Copyright 2009 the V8 project authors. All rights reserved.
      2 // Redistribution and use in source and binary forms, with or without
      3 // modification, are permitted provided that the following conditions are
      4 // met:
      5 //
      6 //     * Redistributions of source code must retain the above copyright
      7 //       notice, this list of conditions and the following disclaimer.
      8 //     * Redistributions in binary form must reproduce the above
      9 //       copyright notice, this list of conditions and the following
     10 //       disclaimer in the documentation and/or other materials provided
     11 //       with the distribution.
     12 //     * Neither the name of Google Inc. nor the names of its
     13 //       contributors may be used to endorse or promote products derived
     14 //       from this software without specific prior written permission.
     15 //
     16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27 
     28 // Flags: --allow-natives-syntax --legacy-const
     29 
     30 // Test the handling of initialization of deleted const variables.
     31 // This only makes sense in local scopes since the declaration and
     32 // initialization of consts in the global scope happen at the same
     33 // time.
     34 
     35 function testIntroduceGlobal() {
     36   var source =
     37       // Deleting 'x' removes the local const property.
     38       "delete x;" +
     39       // Initialization redefines global 'x'.
     40       "const x = 3; assertEquals(3, x);" +
     41       // Test constness of the global 'x'.
     42       "x = 4; assertEquals(3, x);";
     43   eval(source);
     44 }
     45 
     46 testIntroduceGlobal();
     47 assertEquals("undefined", typeof x);
     48 
     49 function testAssignExistingGlobal() {
     50   var source =
     51       // Delete 'x' to remove the local const property.
     52       "delete x;" +
     53       // Initialization redefines global 'x'.
     54       "const x = 5; assertEquals(5, x);" +
     55       // Test constness of the global 'x'.
     56       "x = 6; assertEquals(5, x);";
     57   eval(source);
     58 }
     59 
     60 testAssignExistingGlobal();
     61 assertEquals("undefined", typeof x);
     62 
     63 function testAssignmentArgument(x) {
     64   function local() {
     65     var source = "delete x; const x = 7; assertEquals(7, x)";
     66     eval(source);
     67   }
     68   local();
     69   assertEquals("undefined", typeof x);
     70 }
     71 
     72 for (var i = 0; i < 5; i++) {
     73   testAssignmentArgument();
     74 }
     75 %OptimizeFunctionOnNextCall(testAssignmentArgument);
     76 testAssignmentArgument();
     77 assertEquals("undefined", typeof x);
     78 
     79 __defineSetter__('x', function() { throw 42; });
     80 var finished = false;
     81 function testRedefineGlobal() {
     82   // Initialization redefines global 'x'.
     83   var source = "delete x; const x = 8; finished = true;";
     84   eval(source);
     85 }
     86 
     87 testRedefineGlobal();
     88 assertTrue(finished);
     89 
     90 function testInitFastCaseExtension() {
     91   var source = "const x = 9; assertEquals(9, x); x = 10; assertEquals(9, x)";
     92   eval(source);
     93 }
     94 
     95 testInitFastCaseExtension();
     96 
     97 function testInitSlowCaseExtension() {
     98   var source = "";
     99   // Introduce 100 properties on the context extension object to force
    100   // it in slow case.
    101   for (var i = 0; i < 100; i++) source += ("var a" + i + " = " + i + ";");
    102   source += "const x = 10; assertEquals(10, x); x = 11; assertEquals(10, x)";
    103   eval(source);
    104 }
    105 
    106 testInitSlowCaseExtension();
    107 
    108 function testAssignSurroundingContextSlot() {
    109   var x = 12;
    110   function local() {
    111     var source = "delete x; const x = 13; assertEquals(13, x)";
    112     eval(source);
    113   }
    114   local();
    115   assertEquals(12, x);
    116 }
    117 
    118 testAssignSurroundingContextSlot();
    119