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Edit File: block-scoping.js
// Copyright 2011 the V8 project authors. All rights reserved. // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived // from this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. // Flags: --allow-natives-syntax --harmony-scoping // Test functionality of block scopes. // TODO(ES6): properly activate extended mode "use strict"; // Hoisting of var declarations. function f1() { { var x = 1; var y; } assertEquals(1, x) assertEquals(undefined, y) } f1(); // Dynamic lookup in and through block contexts. function f2(one) { var x = one + 1; let y = one + 2; const u = one + 4; { let z = one + 3; const v = one + 5; assertEquals(1, eval('one')); assertEquals(2, eval('x')); assertEquals(3, eval('y')); assertEquals(4, eval('z')); assertEquals(5, eval('u')); assertEquals(6, eval('v')); } } f2(1); // Lookup in and through block contexts. function f3(one) { var x = one + 1; let y = one + 2; const u = one + 4; { let z = one + 3; const v = one + 5; assertEquals(1, one); assertEquals(2, x); assertEquals(3, y); assertEquals(4, z); assertEquals(5, u); assertEquals(6, v); } } f3(1); // Dynamic lookup from closure. function f4(one) { var x = one + 1; let y = one + 2; const u = one + 4; { let z = one + 3; const v = one + 5; function f() { assertEquals(1, eval('one')); assertEquals(2, eval('x')); assertEquals(3, eval('y')); assertEquals(4, eval('z')); assertEquals(5, eval('u')); assertEquals(6, eval('v')); }; } } f4(1); // Lookup from closure. function f5(one) { var x = one + 1; let y = one + 2; const u = one + 4; { let z = one + 3; const v = one + 5; function f() { assertEquals(1, one); assertEquals(2, x); assertEquals(3, y); assertEquals(4, z); assertEquals(5, u); assertEquals(6, v); }; } } f5(1); // Return from block. function f6() { let x = 1; const u = 3; { let y = 2; const v = 4; return x + y; } } assertEquals(3, f6(6)); // Variable shadowing and lookup. function f7(a) { let b = 1; var c = 1; var d = 1; const e = 1; { // let variables shadowing argument, let, const and var variables let a = 2; let b = 2; let c = 2; let e = 2; assertEquals(2,a); assertEquals(2,b); assertEquals(2,c); assertEquals(2,e); } { // const variables shadowing argument, let, const and var variables const a = 2; const b = 2; const c = 2; const e = 2; assertEquals(2,a); assertEquals(2,b); assertEquals(2,c); assertEquals(2,e); } try { throw 'stuff1'; } catch (a) { assertEquals('stuff1',a); // catch variable shadowing argument a = 2; assertEquals(2,a); { // let variable shadowing catch variable let a = 3; assertEquals(3,a); try { throw 'stuff2'; } catch (a) { assertEquals('stuff2',a); // catch variable shadowing let variable a = 4; assertEquals(4,a); } assertEquals(3,a); } assertEquals(2,a); } try { throw 'stuff3'; } catch (c) { // catch variable shadowing var variable assertEquals('stuff3',c); { // const variable shadowing catch variable const c = 3; assertEquals(3,c); } assertEquals('stuff3',c); try { throw 'stuff4'; } catch(c) { assertEquals('stuff4',c); // catch variable shadowing catch variable c = 3; assertEquals(3,c); } (function(c) { // argument shadowing catch variable c = 3; assertEquals(3,c); })(); assertEquals('stuff3', c); (function() { // var variable shadowing catch variable var c = 3; })(); assertEquals('stuff3', c); c = 2; } assertEquals(1,c); (function(a,b,c,e) { // arguments shadowing argument, let, const and var variable a = 2; b = 2; c = 2; e = 2; assertEquals(2,a); assertEquals(2,b); assertEquals(2,c); assertEquals(2,e); // var variable shadowing var variable var d = 2; })(1,1); assertEquals(1,a); assertEquals(1,b); assertEquals(1,c); assertEquals(1,d); assertEquals(1,e); } f7(1); // Ensure let and const variables are block local // and var variables function local. function f8() { var let_accessors = []; var var_accessors = []; var const_accessors = []; for (var i = 0; i < 10; i++) { let x = i; var y = i; const z = i; let_accessors[i] = function() { return x; } var_accessors[i] = function() { return y; } const_accessors[i] = function() { return z; } } for (var j = 0; j < 10; j++) { y = j + 10; assertEquals(j, let_accessors[j]()); assertEquals(y, var_accessors[j]()); assertEquals(j, const_accessors[j]()); } } f8();