GetMethod.js
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'use strict';
var GetIntrinsic = require('../GetIntrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var GetV = require('./GetV');
var IsCallable = require('./IsCallable');
var IsPropertyKey = require('./IsPropertyKey');
/**
* 7.3.9 - https://ecma-international.org/ecma-262/6.0/#sec-getmethod
* 1. Assert: IsPropertyKey(P) is true.
* 2. Let func be GetV(O, P).
* 3. ReturnIfAbrupt(func).
* 4. If func is either undefined or null, return undefined.
* 5. If IsCallable(func) is false, throw a TypeError exception.
* 6. Return func.
*/
module.exports = function GetMethod(O, P) {
// 7.3.9.1
if (!IsPropertyKey(P)) {
throw new $TypeError('Assertion failed: IsPropertyKey(P) is not true');
}
// 7.3.9.2
var func = GetV(O, P);
// 7.3.9.4
if (func == null) {
return void 0;
}
// 7.3.9.5
if (!IsCallable(func)) {
throw new $TypeError(P + 'is not a function');
}
// 7.3.9.6
return func;
};