const-eval-init.js revision 7f4d5bd8c03935e2c0cd412e561b8fc5a6a880ae 
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27
28// Test the handling of initialization of deleted const variables.
29// This only makes sense in local scopes since the declaration and
30// initialization of consts in the global scope happen at the same
31// time.
32
33function testIntroduceGlobal() {
34  var source =
35      // Deleting 'x' removes the local const property.
36      "delete x;" +
37      // Initialization turns into assignment to global 'x'.
38      "const x = 3; assertEquals(3, x);" +
39      // No constness of the global 'x'.
40      "x = 4; assertEquals(4, x);";
41  eval(source);
42}
43
44testIntroduceGlobal();
45assertEquals(4, x);
46
47function testAssignExistingGlobal() {
48  var source =
49      // Delete 'x' to remove the local const property.
50      "delete x;" +
51      // Initialization turns into assignment to global 'x'.
52      "const x = 5; assertEquals(5, x);" +
53      // No constness of the global 'x'.
54      "x = 6; assertEquals(6, x);";
55  eval(source);
56}
57
58testAssignExistingGlobal();
59assertEquals(6, x);
60
61function testAssignmentArgument(x) {
62  function local() {
63    var source = "delete x; const x = 7; assertEquals(7, x)";
64    eval(source);
65  }
66  local();
67  assertEquals(7, x);
68}
69
70testAssignmentArgument();
71assertEquals(6, x);
72
73__defineSetter__('x', function() { throw 42; });
74function testAssignGlobalThrows() {
75  // Initialization turns into assignment to global 'x' which
76  // throws an exception.
77  var source = "delete x; const x = 8";
78  eval(source);
79}
80
81assertThrows("testAssignGlobalThrows()");
82
83function testInitFastCaseExtension() {
84  var source = "const x = 9; assertEquals(9, x); x = 10; assertEquals(9, x)";
85  eval(source);
86}
87
88testInitFastCaseExtension();
89
90function testInitSlowCaseExtension() {
91  var source = "";
92  // Introduce 100 properties on the context extension object to force
93  // it in slow case.
94  for (var i = 0; i < 100; i++) source += ("var a" + i + " = " + i + ";");
95  source += "const x = 10; assertEquals(10, x); x = 11; assertEquals(10, x)";
96  eval(source);
97}
98
99testInitSlowCaseExtension();
100
101function testAssignSurroundingContextSlot() {
102  var x = 12;
103  function local() {
104    var source = "delete x; const x = 13; assertEquals(13, x)";
105    eval(source);
106  }
107  local();
108  assertEquals(13, x);
109}
110
111testAssignSurroundingContextSlot();
112