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-sloppy --no-legacy-const --harmony-sloppy-let --harmony-sloppy-function 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 // and no function hoisting if there is a conflict. 132 TestFunctionLocal('{ function k() { return 0; } }; k(); let k;'); 133 134 // Test that a function declaration sees the scope it resides in. 135 function f2() { 136 let m, n, o, p; 137 { 138 m = g; 139 function g() { 140 return a; 141 } 142 let a = 1; 143 } 144 assertEquals(1, m()); 145 146 try { 147 throw 2; 148 } catch(b) { 149 n = h; 150 function h() { 151 return b + c; 152 } 153 let c = 3; 154 } 155 assertEquals(5, n()); 156 157 { 158 o = i; 159 function i() { 160 return d; 161 } 162 let d = 4; 163 } 164 assertEquals(4, o()); 165 166 try { 167 throw 5; 168 } catch(e) { 169 p = j; 170 function j() { 171 return e + f; 172 } 173 let f = 6; 174 } 175 assertEquals(11, p()); 176 } 177 f2(); 178 179 // Test that resolution of let bound variables works with scopes that call eval. 180 function outer() { 181 function middle() { 182 function inner() { 183 return x; 184 } 185 eval("1 + 1"); 186 return x + inner(); 187 } 188 189 let x = 1; 190 return middle(); 191 } 192 193 assertEquals(2, outer()); 194
