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