Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2011 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 | "use strict"; |
| 29 | |
| 30 | // Test temporal dead zone semantics of let bound variables in |
| 31 | // function and block scopes. |
| 32 | |
| 33 | function TestFunctionLocal(s) { |
| 34 | try { |
| 35 | eval("(function(){" + s + "; })")(); |
| 36 | } catch (e) { |
| 37 | assertInstanceof(e, ReferenceError); |
| 38 | return; |
| 39 | } |
| 40 | assertUnreachable(); |
| 41 | } |
| 42 | |
| 43 | function TestBlockLocal(s,e) { |
| 44 | try { |
| 45 | eval("(function(){ {" + s + ";} })")(); |
| 46 | } catch (e) { |
| 47 | assertInstanceof(e, ReferenceError); |
| 48 | return; |
| 49 | } |
| 50 | assertUnreachable(); |
| 51 | } |
| 52 | |
| 53 | |
| 54 | function TestAll(s) { |
| 55 | TestBlockLocal(s); |
| 56 | TestFunctionLocal(s); |
| 57 | } |
| 58 | |
| 59 | // Use before initialization in declaration statement. |
| 60 | TestAll('let x = x + 1'); |
| 61 | TestAll('let x = x += 1'); |
| 62 | TestAll('let x = x++'); |
| 63 | TestAll('let x = ++x'); |
| 64 | TestAll('const x = x + 1'); |
| 65 | |
| 66 | // Use before initialization in prior statement. |
| 67 | TestAll('x + 1; let x;'); |
| 68 | TestAll('x = 1; let x;'); |
| 69 | TestAll('x += 1; let x;'); |
| 70 | TestAll('++x; let x;'); |
| 71 | TestAll('x++; let x;'); |
| 72 | TestAll('let y = x; const x = 1;'); |
| 73 | TestAll('let y = x; class x {}'); |
| 74 | |
| 75 | TestAll('f(); let x; function f() { return x + 1; }'); |
| 76 | TestAll('f(); let x; function f() { x = 1; }'); |
| 77 | TestAll('f(); let x; function f() { x += 1; }'); |
| 78 | TestAll('f(); let x; function f() { ++x; }'); |
| 79 | TestAll('f(); let x; function f() { x++; }'); |
| 80 | TestAll('f(); const x = 1; function f() { return x; }'); |
| 81 | TestAll('f(); class x { }; function f() { return x; }'); |
| 82 | |
| 83 | TestAll('f()(); let x; function f() { return function() { return x + 1; } }'); |
| 84 | TestAll('f()(); let x; function f() { return function() { x = 1; } }'); |
| 85 | TestAll('f()(); let x; function f() { return function() { x += 1; } }'); |
| 86 | TestAll('f()(); let x; function f() { return function() { ++x; } }'); |
| 87 | TestAll('f()(); let x; function f() { return function() { x++; } }'); |
| 88 | TestAll('f()(); const x = 1; function f() { return function() { return x; } }'); |
| 89 | TestAll('f()(); class x { }; function f() { return function() { return x; } }'); |
| 90 | |
| 91 | for (var kw of ['let x = 2', 'const x = 2', 'class x { }']) { |
| 92 | // Use before initialization with a dynamic lookup. |
| 93 | TestAll(`eval("x"); ${kw};`); |
| 94 | TestAll(`eval("x + 1;"); ${kw};`); |
| 95 | TestAll(`eval("x = 1;"); ${kw};`); |
| 96 | TestAll(`eval("x += 1;"); ${kw};`); |
| 97 | TestAll(`eval("++x;"); ${kw};`); |
| 98 | TestAll(`eval("x++;"); ${kw};`); |
| 99 | |
| 100 | // Use before initialization with check for eval-shadowed bindings. |
| 101 | TestAll(`function f() { eval("var y = 2;"); x + 1; }; f(); ${kw};`); |
| 102 | TestAll(`function f() { eval("var y = 2;"); x = 1; }; f(); ${kw};`); |
| 103 | TestAll(`function f() { eval("var y = 2;"); x += 1; }; f(); ${kw};`); |
| 104 | TestAll(`function f() { eval("var y = 2;"); ++x; }; f(); ${kw};`); |
| 105 | TestAll(`function f() { eval("var y = 2;"); x++; }; f(); ${kw};`); |
| 106 | } |
| 107 | |
| 108 | // Test that variables introduced by function declarations are created and |
| 109 | // initialized upon entering a function / block scope. |
| 110 | function f() { |
| 111 | { |
| 112 | assertEquals(2, g1()); |
| 113 | assertEquals(2, eval("g1()")); |
| 114 | |
| 115 | // block scoped function declaration |
| 116 | function g1() { |
| 117 | return 2; |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | assertEquals(3, g2()); |
| 122 | assertEquals(3, eval("g2()")); |
| 123 | // function scoped function declaration |
| 124 | function g2() { |
| 125 | return 3; |
| 126 | } |
| 127 | } |
| 128 | f(); |
| 129 | |
| 130 | // Test that a function declaration introduces a block scoped variable. |
| 131 | TestAll('{ function k() { return 0; } }; k(); '); |
| 132 | |
| 133 | // Test that a function declaration sees the scope it resides in. |
| 134 | function f2() { |
| 135 | let m, n, o, p; |
| 136 | { |
| 137 | m = g; |
| 138 | function g() { |
| 139 | return a; |
| 140 | } |
| 141 | let a = 1; |
| 142 | } |
| 143 | assertEquals(1, m()); |
| 144 | |
| 145 | try { |
| 146 | throw 2; |
| 147 | } catch(b) { |
| 148 | n = h; |
| 149 | function h() { |
| 150 | return b + c; |
| 151 | } |
| 152 | let c = 3; |
| 153 | } |
| 154 | assertEquals(5, n()); |
| 155 | |
| 156 | { |
| 157 | o = i; |
| 158 | function i() { |
| 159 | return d; |
| 160 | } |
| 161 | let d = 4; |
| 162 | } |
| 163 | assertEquals(4, o()); |
| 164 | |
| 165 | try { |
| 166 | throw 5; |
| 167 | } catch(e) { |
| 168 | p = j; |
| 169 | function j() { |
| 170 | return e + f; |
| 171 | } |
| 172 | let f = 6; |
| 173 | } |
| 174 | assertEquals(11, p()); |
| 175 | } |
| 176 | f2(); |
| 177 | |
| 178 | // Test that resolution of let bound variables works with scopes that call eval. |
| 179 | function outer() { |
| 180 | function middle() { |
| 181 | function inner() { |
| 182 | return x; |
| 183 | } |
| 184 | eval("1 + 1"); |
| 185 | return x + inner(); |
| 186 | } |
| 187 | |
| 188 | let x = 1; |
| 189 | return middle(); |
| 190 | } |
| 191 | |
| 192 | assertEquals(2, outer()); |