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    mocked-env
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    1.3.5 • Public • Published

    mocked-env

    Easy way to mock process.env during BDD testing

    NPM

    Build status semantic-release standard renovate-app badge

    Read Mocking process.env blog post.

    Install

    Requires Node version 6 or above.

    npm install --save-dev mocked-env

    Use

    Change values

    const mockedEnv = require('mocked-env')
    // before the test
    let restore = mockedEnv({
      FOO: 'fake foo value',
      BAR: '42',
    })
    // use process.env.FOO and process.env.BAR during testing
    // process.env.FOO = "fake foo value"
    // process.env.BAR = "42"
    // after the test
    restore()
    // any previous values of FOO and BAR restored

    Delete values

    If you want to temporarily delete environment variable, pass undefined value

    let restore = mockedEnv({
      FOO: 'fake foo value',
      PWD: undefined, // will be deleted from process.env
    })

    Clear entire object

    If you want to remove all existing properties and just set some, use option clear: true

    let restore = mockedEnv(
      {
        FOO: 'foo',
        BAR: 'bar',
      },
      { clear: true }
    )
    // process.env = {FOO: 'foo', BAR: 'bar'}

    Again, calling restore() will restore the original full process.env object.

    Restore environment without clearing

    If you want to maintain the current environment and restore it to the original state after restore() is called, pass the 'restore' option.

    let restore = mockedEnv(
      {
        FOO: 'foo',
        BAR: 'bar',
      },
      { restore: true }
    )
    // process.env = {...process.env, FOO: 'foo', BAR: 'bar'}

    These options are mutually exclusive and specifying them both will result in an error.

    Options as first argument

    The options array can be passed as the first argument to the mockedEnv function as long as it contains either a 'restore' or 'clear' key, not both.

    let restore = mockedEnv(
      { clear: true }
    )
    // process.env = {}

    ⚠️ Note: process.env values should always be strings (Stackoverflow), any call to mockedEnv that attempts to use values other than strings (or undefined to signify that a property should be deleted) will raise an error.

    Example

    const mockedEnv = require('mocked-env')
    describe('changes variables', () => {
      let restore // to restore old values
    
      beforeEach(() => {
        restore = mockedEnv({
          PWD: '/foo/bar',
          USER: undefined, // will be deleted from process.env
        })
      })
    
      it('has changed process.env', () => {
        // process.env.PWD = '/foo/bar'
      })
    
      afterEach(() => restore())
    })

    See src/example-spec.js

    You can also nest process.env reset and setting individual values in inner suites, see src/nested-spec.js. Great for tests that need to control process.env and would like to reset the entire thing, but then mock individual properties.

    Debugging

    Run with DEBUG=mocked-env environment variable.

    More information

    This package was inspired by burl/mock-env

    Small print

    Author: Gleb Bahmutov <gleb.bahmutov@gmail.com> © 2018

    License: MIT - do anything with the code, but don't blame me if it does not work.

    Support: if you find any problems with this module, email / tweet / open issue on Github

    MIT License

    Copyright (c) 2018 Gleb Bahmutov <gleb.bahmutov@gmail.com>

    Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

    Install

    npm i mocked-env

    DownloadsWeekly Downloads

    160,020

    Version

    1.3.5

    License

    MIT

    Unpacked Size

    12 kB

    Total Files

    4

    Last publish

    Collaborators

    • bahmutov