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 // Flags: --harmony-scoping 29 30 // TODO(ES6): properly activate extended mode 31 "use strict"; 32 33 // Test temporal dead zone semantics of let bound variables in 34 // function and block scopes. 35 36 function TestFunctionLocal(s) { 37 try { 38 eval("(function(){" + s + "; })")(); 39 } catch (e) { 40 assertInstanceof(e, ReferenceError); 41 return; 42 } 43 assertUnreachable(); 44 } 45 46 function TestBlockLocal(s,e) { 47 try { 48 eval("(function(){ {" + s + ";} })")(); 49 } catch (e) { 50 assertInstanceof(e, ReferenceError); 51 return; 52 } 53 assertUnreachable(); 54 } 55 56 57 function TestAll(s) { 58 TestBlockLocal(s); 59 TestFunctionLocal(s); 60 } 61 62 // Use before initialization in declaration statement. 63 TestAll('let x = x + 1'); 64 TestAll('let x = x += 1'); 65 TestAll('let x = x++'); 66 TestAll('let x = ++x'); 67 TestAll('const x = x + 1'); 68 69 // Use before initialization in prior statement. 70 TestAll('x + 1; let x;'); 71 TestAll('x = 1; let x;'); 72 TestAll('x += 1; let x;'); 73 TestAll('++x; let x;'); 74 TestAll('x++; let x;'); 75 TestAll('let y = x; const x = 1;'); 76 77 TestAll('f(); let x; function f() { return x + 1; }'); 78 TestAll('f(); let x; function f() { x = 1; }'); 79 TestAll('f(); let x; function f() { x += 1; }'); 80 TestAll('f(); let x; function f() { ++x; }'); 81 TestAll('f(); let x; function f() { x++; }'); 82 TestAll('f(); const x = 1; function f() { return x; }'); 83 84 TestAll('f()(); let x; function f() { return function() { return x + 1; } }'); 85 TestAll('f()(); let x; function f() { return function() { x = 1; } }'); 86 TestAll('f()(); let x; function f() { return function() { x += 1; } }'); 87 TestAll('f()(); let x; function f() { return function() { ++x; } }'); 88 TestAll('f()(); let x; function f() { return function() { x++; } }'); 89 TestAll('f()(); const x = 1; function f() { return function() { return x; } }'); 90 91 // Use before initialization with a dynamic lookup. 92 TestAll('eval("x + 1;"); let x;'); 93 TestAll('eval("x = 1;"); let x;'); 94 TestAll('eval("x += 1;"); let x;'); 95 TestAll('eval("++x;"); let x;'); 96 TestAll('eval("x++;"); let x;'); 97 TestAll('eval("x"); const x = 1;'); 98 99 // Use before initialization with check for eval-shadowed bindings. 100 TestAll('function f() { eval("var y = 2;"); x + 1; }; f(); let x;'); 101 TestAll('function f() { eval("var y = 2;"); x = 1; }; f(); let x;'); 102 TestAll('function f() { eval("var y = 2;"); x += 1; }; f(); let x;'); 103 TestAll('function f() { eval("var y = 2;"); ++x; }; f(); let x;'); 104 TestAll('function f() { eval("var y = 2;"); x++; }; f(); let x;'); 105 106 // Test that variables introduced by function declarations are created and 107 // initialized upon entering a function / block scope. 108 function f() { 109 { 110 assertEquals(2, g1()); 111 assertEquals(2, eval("g1()")); 112 113 // block scoped function declaration 114 function g1() { 115 return 2; 116 } 117 } 118 119 assertEquals(3, g2()); 120 assertEquals(3, eval("g2()")); 121 // function scoped function declaration 122 function g2() { 123 return 3; 124 } 125 } 126 f(); 127 128 // Test that a function declaration introduces a block scoped variable. 129 TestAll('{ function k() { return 0; } }; k(); '); 130 131 // Test that a function declaration sees the scope it resides in. 132 function f2() { 133 let m, n, o, p; 134 { 135 m = g; 136 function g() { 137 return a; 138 } 139 let a = 1; 140 } 141 assertEquals(1, m()); 142 143 try { 144 throw 2; 145 } catch(b) { 146 n = h; 147 function h() { 148 return b + c; 149 } 150 let c = 3; 151 } 152 assertEquals(5, n()); 153 154 { 155 o = i; 156 function i() { 157 return d; 158 } 159 let d = 4; 160 } 161 assertEquals(4, o()); 162 163 try { 164 throw 5; 165 } catch(e) { 166 p = j; 167 function j() { 168 return e + f; 169 } 170 let f = 6; 171 } 172 assertEquals(11, p()); 173 } 174 f2(); 175 176 // Test that resolution of let bound variables works with scopes that call eval. 177 function outer() { 178 function middle() { 179 function inner() { 180 return x; 181 } 182 eval("1 + 1"); 183 return x + inner(); 184 } 185 186 let x = 1; 187 return middle(); 188 } 189 190 assertEquals(2, outer()); 191
