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Lax streaming tap parser


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Tub is a streaming tap parser that serves two purposes.

  • It's a writable stream that collects and determines the end result of the tests output. It collects assert results, failed asserts, and creates a summary string, and an ok bool to be able to determine easily from a callback what happened.

  • When piped to, the result is a readable stream, in that it provides a shorter, comment free output that can be piped to stdout for information as the tests are running.

It's based on streams2, and inherits from stream.Transform to accomplish this, so you will need node >= 0.10.


The tap parser itself is a little more relaxed than most tap parsers, in that numbers does not need to exist in the tap output, as long as the amount of tests add up to what's in the plan. It also deals with the Bail out! statement.

It will also ignore lines it cannot parse as valid TAP by default. To throw on such error pass a {strict:true} option.

Library Usage

Custom Logger

Create your own customized results logger for command line use:

// tubber.js 
var tub = require('tub');
var splitter = require('splitter');
var fullOutput = Boolean(process.argv[2]);
var onFinish = function (res) {
  process.exit(res.ok ? 0 : 1)
  .pipe(fullOutput ? process.stdout : devNull());

then hook into some raw tap output (perhaps from the tap module) and hand it over to your script!

$ tap test/*.js --tap | node tubber.js

which would give you the raw output like the following

{ plan: { start: 1, end: 5 },
   [ { ok: true, number: 1, name: 'upvotes good', info: [] },
     { ok: true, number: 2, name: 'downvotes bad', info: [] },
     { ok: true,
       number: 3,
       name: 'higher confidence means lowers bounds',
       info: [] },
     { ok: false,
       number: 4,
       name: 'this will fail deliberately',
       info: [Object] },
     { ok: true, number: 5, name: 'upvotes good', info: [] } ],
  version: 13,
   [ { ok: false,
       number: 4,
       name: 'this will fail deliberately',
       info: [Object] } ],
  ok: false,
  summary: '1 / 5 assertions failed' }

Failed asserts gets copied to the failed list. When using output from tap, every failed test will have an info list which can be joined to produce the normal stack trace that normally accompanies them:

// add this line to `onFinish` 

which will give the following extra output:

    file:   /home/clux/repos/decay/test/all.js
    line:   22
    column: 5
      - getCaller (/home/clux/local/node/lib/node_modules/tap/lib/tap-assert.js:418:17)
      - Function.assert (/home/clux/local/node/lib/node_modules/tap/lib/tap-assert.js:21:16)
      - Test._testAssert [as ok] (/home/clux/local/node/lib/node_modules/tap/lib/tap-test.js:86:16)
      - Test.<anonymous> (/home/clux/repos/decay/test/all.js:22:5)
      - Test.EventEmitter.emit (events.js:117:20)
      - Test.emit (/home/clux/local/node/lib/node_modules/tap/lib/tap-test.js:103:8)
      - GlobalHarness.Harness.process (/home/clux/local/node/lib/node_modules/tap/lib/tap-harness.js:86:13)
      - process._tickCallback (node.js:415:13)
      - Function.Module.runMain (module.js:499:11)
      - startup (node.js:119:16)

But info can be set on any assert. It's just indented output belonging to the previous assertion.

Parsing Logs

  .pipe(fullOutput ? process.stdout : devNull());

Global Usage

Bunbled bin file will read TAP from stdin:

$ npm install -g tub
$ tap test/*.js | tub
✗ 1 / 61 assertions failed
7 name of failed test
    file:   /home/clux/repos/failedTestRepo/test.js
    stack:  stack trace lines would follow here

To see every assert, you can add the -a flag to tub:

$ tap test/*.js | tub -a
✓ 1 1-dim identity
✓ 2 noop
✓ 3 constant
✓ 4 !false
✓ 5 range/elem filter
✓ 6 range/elem filter
✗ 7 woot
    file:   /home/clux/repos/failedTestRepo/test.js
    stack:  stack trace lines would follow here
✓ 8 primes 5,3 are coprime
✓ 9 21 and 14 have 7 as gcd
more tests
✗ 1 / 61 assertions failed
✗ 7 woot
    file:   /home/clux/repos/failedTestRepo/test.js
    stack:  stack trace lines would follow here


MIT-Licensed. See LICENSE file for details.