// Copyright 2015 Mike Pennisi. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- es6id: 8.1.1.2.1 description: > True-coercing `Symbol.unscopables` properties block access to object environment record info: | [...] 6. If the withEnvironment flag of envRec is false, return true. 7. Let unscopables be Get(bindings, @@unscopables). 8. ReturnIfAbrupt(unscopables). 9. If Type(unscopables) is Object, then a. Let blocked be ToBoolean(Get(unscopables, N)). b. ReturnIfAbrupt(blocked). c. If blocked is true, return false. ES6: 13.11.7 (The `with` Statement) Runtime Semantics: Evaluation [...] 6. Set the withEnvironment flag of newEnv’s EnvironmentRecord to true. [...] flags: [noStrict] features: [Symbol.unscopables] ---*/ var x = 0; var env = { x: 1 }; env[Symbol.unscopables] = { x: true }; with (env) { assert.sameValue(x, 0, 'literal `true` value'); } env[Symbol.unscopables].x = 'string'; with (env) { assert.sameValue(x, 0, 'non-empty string values'); } env[Symbol.unscopables].x = 86; with (env) { assert.sameValue(x, 0, 'non-zero number values'); } env[Symbol.unscopables].x = {}; with (env) { assert.sameValue(x, 0, 'object values'); } env[Symbol.unscopables].x = Symbol.unscopables; with (env) { assert.sameValue(x, 0, 'Symbol values'); }