| // Copyright (C) 2016 The V8 Project authors. All rights reserved. |
| // This code is governed by the BSD license found in the LICENSE file. |
| |
| /*--- |
| esid: sec-number.prototype.toprecision |
| description: > |
| Return a string containing the the number value of this if precision is |
| undefined |
| info: | |
| 20.1.3 Properties of the Number Prototype Object |
| |
| The Number prototype object is the intrinsic object %NumberPrototype%. The |
| Number prototype object is an ordinary object. The Number prototype is itself |
| a Number object; it has a [[NumberData]] internal slot with the value +0. |
| |
| [...] |
| The abstract operation thisNumberValue(value) performs the following steps: |
| |
| 1. If Type(value) is Number, return value. |
| 2. If Type(value) is Object and value has a [[NumberData]] internal slot, then |
| a. Assert: value's [[NumberData]] internal slot is a Number value. |
| b. Return the value of value's [[NumberData]] internal slot. |
| 3. Throw a TypeError exception. |
| |
| Number.prototype.toPrecision ( precision ) |
| |
| 1. Let x be ? thisNumberValue(this value). |
| 2. If precision is undefined, return ! ToString(x). |
| [...] |
| ---*/ |
| |
| var n = new Number(7); |
| |
| assert.sameValue(n.toPrecision(undefined), "7"); |
| assert.sameValue((39).toPrecision(undefined), "39"); |
| |
| assert.sameValue(Number.prototype.toPrecision(), "0"); |
| assert.sameValue((42).toPrecision(), "42"); |