Node Test Helpers

@mhio/test

Collection of Node.js Test Helpers.

TestEnv sets up up a read/write environment that can be easily accessed, populated and then cleaned up after a test run.

Install

    npm install @mhio/test --save-dev
    yarn add @mhio/test --dev

Usage

TestEnv expects test to contain you test files by default. Fixtures are expected to be in test/fixture. Output goes into test/output.

These paths can be overridden when you setup your TestEnv.

See examples for more

let test_env, out

before('Copy `files` from fixtures', function(){
  // Create a test environment from a file in your `test/` directory.
  test_env = TestEnv.setupTestDir(__dirname)

  // Create an output area called `newdir` in `test/output/newdir`.
  out = test_env.output('newdir')

  // Copy `test/fixture/files` to `test/output/subdir`
  return out.copyFrom('files', 'subdir')
})

after('Cleanup', function(){
  return out.clean()
})

it('should now have fixtures in the output directory', function(){
  let dir = out.path('subdir')
  expect( dir ).to.be.a.directory().with.contents(['firstfile'])
})

it('should write a file to output', function(){
  let file = out.path('subdir', 'testfile')
  return fs.writeFileAsync(file, 'data\n').then( ()=> {
    expect( path.join(__dirname,'output','newdir','subdir','testfile') ).to.be.a.file()
  })
})

Setting DEBUG_CLEAN=true in your environment prevents cleanup so you can inspect files after the tests have run.

DEBUG_CLEAN=true mocha -b

API

TestEnvPath

`.path( ...dirs )`

Create a path from the base path of this Path instance

`copy( source, destination )`

Promise to copy a file from a source to destination

TestEnvPathOutput

`copyTo( source, destination )`

Promise to copy data to this Output or path from a Fixture or path

Source and destination can be:

undefined/null - Parents fixture path.
String - Parents fixture path + str
Array - Parents fixture path join with Array
TestEnvPath - TEP's base bath

`clean()`

Promise to clean up file system contents of this Path instance

TestEnvPathFixture

`copyFrom( source, destination )`

Promise to copy data from this Fixture or path to an Output or path

Source and destination can be:

undefined/null - Parents fixture path.
String - Parents fixture path + str
Array - Parents fixture path join with Array
TestEnvPath - TEP's base bath

TestEnv

`TestEnv.setup( app_path )`

Requires the path to your app directory that contains test. The fixture and output directories will be in test. See TestEnv.setupTestDir( __dirname ) for quicker setup from your inside your tests.

Options

base_path
The project/apps base path. Take a guess if the user doesn't provide one. The guess removes the node_modules/@mhio/test/lib dirs.
test_dir
This directory will be appended to base_path that contains your tests. Defaults to: test
fixture_dir
This directory will be appended to test_dir and contains your fixtures. Defaults to: fixture
output_dir
This directory will be appended to test_dir for test output. Defaults to: output
tmp_output_dir_prefix The prefix used for a temp dirs in output. Defaults to tmp-

`TestEnv.setupTestDir( test_dir )`

Same as above but accepts the test directory instead of the app path. Allows TestEnv.setupTestDir( __dirname ) from test files.

`basePath(...args)`

Return a directory path from TestEnv base_path. Joins all arguments with path.join

`fixturePath(...args)`

Return a directory path from the fixture/ path Joins all arguments with path.join

TestEnv.fixturePath('a', 'b')
// = '/project/test/fixture/a/b'

`outputPath(...args)`

Return a directory from the output/ path Joins all arguments with path.join

TestEnv.outputPath('one', 'two')
// = '/project/test/output/one/two'

`tmpOutputPath(suffix, ...extras)`

Return a random tmp dir path in the output path

TestEnv.tmpOutputPath('blah', 'one', 'two')
// = '/project/test/output/tmp-blah/one/two'

`randomHex(n)`

Create a random hex string n chars long

TestEnv.randomHex(5)
// = 'c8fd2'