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kapok-js

v0.10.1

Published

Javascript Testing utilities for CLI

Readme

kapok-js

Build Status CircleCI

Javascript Testing utilities for CLI

Table of Contents

Installation

yarn add -D kapok-js

Usage

import Kapok from 'kapok-js';

const kapok = new Kapok('echo', ['hello\nworld']);
kapok.assert('hello').assert('world');
Advanced Usage
import Kapok from 'kapok-js';
import { isEqual } from 'lodash';

const code = `
  console.log('🌺');
  console.log('* * *');
  console.log('start');
  console.log(JSON.stringify({ hello: 'world' }, null, 2));
  console.log('end');
`;

/*
🌺
* * *
start
{
  "hello": "world"
}
end
*/

const kapok = new Kapok('node', ['-e', code]); /* just like childProcess.spawn() */
kapok
  .ignoreUntil(/\*/) /* ignore lines until the line matches "*" */
  .assert('start')
  .joinUntil('}') /* join multi lines until the line is equal to '}', and then join the lines into a string */
  .assert((message) => isEqual({ hello: 'world' }, JSON.parse(message)))
  .assert('end')
  .done(() => {
    console.log('done');
  })
;

API

Kapok.config

  • config.shouldShowLog <Boolean>: Show log message or not. Defaults to true
  • config.shouldThrowError <Boolean>: Throw a new Error or not when assert fails. Defaults to false

A global config to all Kapok instances. Can be override.


Kapok.start(command[, args][, options])

  • command <String>: The command to run
  • args <Array>: List of string arguments
  • options <Object>: Just like spawn options
  • Returns <Kapok>

Spawns a new process using the given command, just like child_process.spawn(), but returns a Kapok instance.

Kapok inherits EventEmitter


Kapok.size

  • Returns <Number>

Get existing kapok instances size


Kapok.killAll()

  • Return <Promise>

Kill all existing kapok instances


Kapok#constructor(command[, args][, options])

The same with Kapok.start()


Kapok#assert(condition[, options])

  • condition <String|RegExp|Function>: Testing message, throw an error if returns false. The message is the each line data of process outputs
    • If is a String, it will return message === condition
    • If is a RegExp, it will return condition.test(message)
    • If is a Function, it will return condition(message, lines)
      • message <String>: Data message of each line
      • lines <Array>: An array of data. A data includes message and ansiMessage. ansiMessage is like message, but includes some ANSI code.
  • options <String|Object>
    • errorMessage <String>: If condition returns false, it will throw a new error with the message. If the options is a String, it will become a short hand of options.errorMessage
    • action <Function>: An addition function to do something while assert function fires. Support returning a promise for async action
    • shouldShowLog <Boolean>: Show log message or not. Defaults to Kapok.config.shouldShowLog
    • shouldThrowError <Boolean>: Throw a new Error or not when assert fails. Defaults to Kapok.config.shouldThrowError
  • Returns <Kapok>

Iterate each line of the process outputs, and assert the data message of each line.

Example
const kapok = new Kapok('echo', ['a\nb\nc']);
kapok
  .assert('a') /* using `String` */
  .assert(/b/) /* using `RegExp` */
  .assert((message) => message === 'c') /* using `Function` */
  .done()
;

Kapok#joinUntil(condition[, options])

  • condition <Number|String|RegExp|Function>: Decide when to stop grouping lines
    • If is a Number, it will return true if the delta line number is equal with condition number
    • If is a String, it will return message === condition
    • If is a RegExp, it will return condition.test(message)
    • If is a Function, it will return condition(message, lines)
  • options <Object>
    • join <String|Function|false>: Join the grouped messages into a string
      • If is a String, it will join messages by messages.join(joinString)
      • If is a Function, it will join messages by join(lines)
      • If is false, it won't join messages
      • By default, it is an empty string
    • action <Function>: An addition function to do something while condition matched. Support returning a promise for async action
    • shouldShowLog <Boolean>: Show log message or not. Defaults to Kapok.config.shouldShowLog
  • Returns <Kapok>

A helper function to join multi lines into a string and pass to the next assert(). Joining function will stop when condition() matched.

Example
const input = { a: 'hello', b: 'world' };
const code = `
  var data = eval(${JSON.stringify(input)});
  console.log(JSON.stringify(data, null, 2));
`;
const kapok = new Kapok('node', ['-e', code]);
kapok
  .joinUntil('}')
  .assert((message) => {
    const json = JSON.parse(message);
    return isEqual(json, input);
  })
  .done()
;

Kapok#until(condition[, options])

  • condition <Number|String|RegExp|Function>: Decide when to start to assert next line
    • If is a Number, it will return true if the delta line number is equal with condition number
    • If is a String, it will return message === condition
    • If is a RegExp, it will return condition.test(message)
    • If is a Function, it will return condition(message, lines)
  • options <Object>
    • action <Function>: An addition function to do something while condition matched. Support returning a promise for async action
    • shouldShowLog <Boolean>: Show log message or not. Defaults to Kapok.config.shouldShowLog
  • Returns <Kapok>

Message will not pass to the next assert() until condition() matched.

Example
const kapok = new Kapok('echo', ['# a\n# b\nc']);
kapok.until(/^[^#]/).assert('c').done(); /* lines before 'c' would be ignored */

Kapok#assertUntil(condition[, options])

  • condition <Number|String|RegExp|Function>: Decide when to start to assert
    • If is a Number, it will return true if the delta line number is equal with condition number
    • If is a String, it will return message === condition
    • If is a RegExp, it will return condition.test(message)
    • If is a Function, it will return condition(message, lines)
  • options <Object>
    • action <Function>: An addition function to do something while condition matched. Support returning a promise for async action
    • shouldShowLog <Boolean>: Show log message or not. Defaults to Kapok.config.shouldShowLog
  • Returns <Kapok>

Message will not pass to the next assert() until condition() matched.

Example
const kapok = new Kapok('echo', ['# a\n# b\nc']);
kapok.assertUntil('c').done(); /* lines before 'c' would be ignored */

Kapok#ignoreUntil(condition[, options])

  • condition <Number|String|RegExp|Function>: Decide when to stop ignoring
    • If is a Number, it will return true if the delta line number is equal with condition number
    • If is a String, it will return message === condition
    • If is a RegExp, it will return condition.test(message)
    • If is a Function, it will return condition(message, lines)
  • options <Object>
    • action <Function>: An addition function to do something while condition matched. Support returning a promise for async action
    • shouldShowLog <Boolean>: Show log message or not. Defaults to Kapok.config.shouldShowLog
  • Returns <Kapok>

A little like .until(), but .ignoreUntil() will event ignore the last line of the matched condition().

Example
const kapok = new Kapok('echo', ['# a\n# b\nc']);
kapok.ignoreUntil(/^#/).assert('c'); /* lines before 'c' would be ignored */

Kapok#done([callback])

  • callback <Function>: Provide a callback function. If there's no error, the first argument is undefined, otherwise, the first argument is an array of errors
  • Returns <Promise>

Stop asserting. Could provide a callback function or return a promise for async function.

Example

Using jest

const kapok = new Kapok('echo', ['hello']);

test('echo', async () => kapok.assert('hello').done());

Kapok#doneAndKill([callback])

  • callback <Function>: Provide a callback function. If there's no error, the first argument is undefined, otherwise, the first argument is an array of errors
  • Returns <Promise>

Like done(), but also kill the process after stop asserting.


Kapok#kill([signal, callback])

  • callback <Function>: Provide a callback function.
  • Returns <Promise>

Killing kapok process. Could provide a callback function or return a promise for async function.


Event: 'data'

  • data <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The data event will emitted when the stdout or stderr output data.

Event: 'out:data'

  • data <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The out:data event will emitted when the stdout output data.

Event: 'err:data'

  • data <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The err:data event will emitted when the stderr output data.

Event: 'line'

  • line <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The line event will emitted when the stdout or stderr output each lines.

Event: 'out:line'

  • line <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The out:line event will emitted when the stdout output each lines.

Event: 'err:line'

  • line <Object>
    • message <String>: Data message
    • ansiMessage <String>: Data message includes ANSI code

The err:line event will emitted when the stderr output each lines.

Event: 'error'

The same with child_process error event

Event: 'exit'

The same with child_process exit event

Event: 'signal:exit'

  • code <String>: Exit code
  • signal <String>: Signal

The signal:exit event will emitted when receive SIG* exit event.

License

MIT