Adding support to es6 Set collection #183
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| * Returns true if the given object is a set. | ||
| */ | ||
| export const isSet = (object) => | ||
| object instanceof Set |
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this check is unreliable across realms (like iframes). instanceof shouldn't be used.
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You'd need to cache the getter from Set.prototype.size, and .call it in a try/catch, in order to reliably detect Sets.
| * indicate a non-match. | ||
| */ | ||
| export const setContains = (set, value, compareValues) => | ||
| arrayContains([ ...set ], value, compareValues) |
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it's a Set - why would we want to reify it as a real array, when it's got .has() which is O(1)?
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Set#has is using identity equality (===) so new Set([ {} ]).has({}) is false.
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In that case, Set.prototype.forEach.call(set, x => compareValues(value, x)) would be more efficient (but some engines don't have forEach, so you'd need to use Function and for..of there)
| @@ -1,10 +1,10 @@ | |||
| import expect from '../index' | |||
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| describe('toExclude', () => { | |||
| it('requires the actual value to be an array or string', () => { | |||
| it('requires the actual value to be an array, set, object or string', () => { | |||
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i think "object" is sufficient here, since a Set is an object.
| * Returns true if the given object is a set. | ||
| */ | ||
| export const isSet = (object) => | ||
| Object.prototype.toString.call(object) === '[object Set]' |
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this is fakeable since ES6 has Symbol.toStringTag - Object#toString output is not reliable >= ES6
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So what what would you think be better? object[Symbol.toStringTag] === 'Set' or object[Symbol.iterator] !== undefined?
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There is only one possible solution, which I mentioned earlier
| it('does not throw when an object contains an expected object with an unexpected value', () => { | ||
| expect(() => { | ||
| expect({ a: 1 }).toExclude({ a: 2 }) | ||
| }).toNotThrow() | ||
| }) | ||
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| it('does not throw when an array does not contain the expected value', () => { | ||
| it('does not throw when an string does not contain the expected value', () => { |
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Hi, Any idea what should be done? |
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If there's a bug in |
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(the object-inspect bug is filed here, and it turns out it's a bug in core-js/babel-polyfill) |
| @@ -55,7 +55,7 @@ module.exports = (config) => { | |||
| reporters: [ 'mocha' ], | |||
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| files: [ | |||
| 'node_modules/babel-polyfill/dist/polyfill.js', | |||
| 'node_modules/es6-shim/es6-shim.js', | |||
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fwiw since this is JS, this can probably do path.relative(require.resolve('es6-shim'), process.cwd()) or something similar
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object-inspect has a workaround for core-js's broken Map/Set implementation in v1.3.0, and separately, core-js fixed it in v2.5.0. |
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This package is no longer being updated; v21+ is maintained here |
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