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			47 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| // Copyright (C) 2020 Alexey Shvayka. All rights reserved.
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| // This code is governed by the BSD license found in the LICENSE file.
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| 
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| /*---
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| esid: sec-array.from
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| description: >
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|   Non-writable properties are overwritten by CreateDataProperty.
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|   (result object's "0" is non-writable, items is not iterable)
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| info: |
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|   Array.from ( items [ , mapfn [ , thisArg ] ] )
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| 
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|   [...]
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|   4. Let usingIterator be ? GetMethod(items, @@iterator).
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|   5. If usingIterator is not undefined, then
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|     [...]
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|   6. NOTE: items is not an Iterable so assume it is an array-like object.
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|   [...]
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|   12. Repeat, while k < len
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|     [...]
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|     e. Perform ? CreateDataPropertyOrThrow(A, Pk, mappedValue).
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|   [...]
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| includes: [propertyHelper.js]
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| ---*/
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| 
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| var items = {
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|   "0": 2,
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|   length: 1,
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| };
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| 
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| var A = function(_length) {
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|   Object.defineProperty(this, "0", {
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|     value: 1,
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|     writable: false,
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|     enumerable: false,
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|     configurable: true,
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|   });
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| };
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| 
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| var res = Array.from.call(A, items);
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| 
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| verifyProperty(res, "0", {
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|   value: 2,
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|   writable: true,
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|   enumerable: true,
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|   configurable: true,
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| });
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