tap-parser

What is tap-parser?

The tap-parser npm package is a TAP (Test Anything Protocol) parser for Node.js. It allows you to parse TAP output, which is a standard format for test results, and provides a way to handle the parsed data programmatically.

What are tap-parser's main functionalities?

Parsing TAP output

This feature allows you to parse TAP output and handle assertions and results. The code sample demonstrates how to create a parser instance, listen for 'assert' and 'complete' events, and parse a simple TAP string.

const Parser = require('tap-parser');
const parser = new Parser();

parser.on('assert', assert => {
  console.log('assertion:', assert);
});

parser.on('complete', results => {
  console.log('results:', results);
});

parser.end('TAP version 13
ok 1 - this is fine
not ok 2 - this is not fine
1..2
');

Handling TAP comments

This feature allows you to handle comments in TAP output. The code sample demonstrates how to listen for 'comment' events and parse a TAP string that includes a comment.

const Parser = require('tap-parser');
const parser = new Parser();

parser.on('comment', comment => {
  console.log('comment:', comment);
});

parser.end('TAP version 13
# this is a comment
ok 1 - this is fine
');

Handling TAP plan

This feature allows you to handle the TAP plan, which specifies the number of tests expected. The code sample demonstrates how to listen for 'plan' events and parse a TAP string that includes a plan.

const Parser = require('tap-parser');
const parser = new Parser();

parser.on('plan', plan => {
  console.log('plan:', plan);
});

parser.end('TAP version 13
1..2
ok 1 - this is fine
ok 2 - this is also fine
');

Other packages similar to tap-parser

tap

The 'tap' package is a comprehensive TAP producer and consumer for Node.js. It includes a test runner, assertion library, and TAP parser. Compared to tap-parser, 'tap' offers a more complete testing framework but is heavier and more feature-rich.

tap-out

The 'tap-out' package is another TAP parser that focuses on providing a simple interface for parsing TAP output. It is similar to tap-parser but offers a different API and may be preferred for its simplicity and ease of use.

tap-consumer

The 'tap-consumer' package is designed to consume TAP output and provide a structured representation of the test results. It is similar to tap-parser but focuses more on consuming and structuring the data rather than just parsing it.

README

tap-parser

parse the test anything protocol

example

var parser = require('tap-parser');
var p = parser(function (results) {
    console.dir(results);
});

process.stdin.pipe(p);

given some TAP-formatted input:

$ node test.js
TAP version 13
# beep
ok 1 should be equal
ok 2 should be equivalent
# boop
ok 3 should be equal
ok 4 (unnamed assert)

1..4
# tests 4
# pass  4

# ok

parse the output:

$ node test.js | node parse.js
{ ok: true, count: 4, pass: 4, plan: { start: 1, end: 4 } }

usage

This package also has a tap-parser command.

Usage:
  tap-parser [-j [<indent>] | --json[=indent]]

Parses TAP data from stdin, and outputs an object representing
the data found in the TAP stream to stdout.

If there are any failures in the TAP stream, then exits with a
non-zero status code.

Data is output by default using node's `util.format()` method, but
JSON can be specified using the `-j` or `--json` flag with a number
of spaces to use as the indent (default=2).

methods

var parser = require('tap-parser')

var p = parser(options, cb)

Return a writable stream p that emits parse events.

If cb is given it will listen for the 'complete' event.

If options is given, it may contain the following flags:

• preserveWhitespace boolean which is false by default and will cause the parser to emit line events even for lines containing only whitespace. (Whitespace lines in yaml blocks are always emitted, because whitespace is semantically relevant for yaml.)

• strict boolean which is false by default and causes the parser to treat non-TAP input as a failure. Strictness is heritable to child subtests. You can also turn strictness on or off by using the pragma +strict line in the TAP data to turn strictness on, or pragma -strict to turn strictness off.

The parent, level and buffered options are reserved for internal use.

events

p.on('complete', function (results) {})

The results object contains a summary of the number of tests skipped, failed, passed, etc., as well as a boolean ok member which is true if and only if the planned test were all found, and either "ok" or marked as "TODO".

p.on('assert', function (assert) {})

Every /^(not )?ok\b/ line will emit an 'assert' event.

Every assert object has these keys:

• assert.ok - true if the assertion succeeded, false if failed
• assert.id - the assertion number
• assert.name - optional short description of the assertion

and may also have

• assert.todo - optional description of why the assertion failure is not a problem. (Boolean true if no explaination provided)
• assert.skip - optional description of why this assertion was skipped (boolean true if no explanation provided)
• assert.diag - a diagnostic object with additional information about the test point.

p.on('comment', function (comment) {})

Every /^# (.+)/ line will emit the string contents of comment.

p.on('plan', function (plan) {})

Every /^\d+\.\.\d+/ line emits a 'plan' event for the test numbers plan.start through plan.end, inclusive.

If the test is completely skipped the result will look like

{ ok: true,
  count: 0,
  pass: 0,
  plan:
   { start: 1,
     end: 0,
     skipAll: true,
     skipReason: 'This code has no seat belt' } }

p.on('version', function (version) {})

A /^TAP version (\d+)/ line emits a 'version' event with a version number or string.

p.on('bailout', function (reason) {})

A bail out! line will cause the parser to completely stop doing anything. Child parser bailouts will bail out their parents as well.

p.on('child', function (childParser) {})

If a child test set is embedded in the stream like this:

TAP Version 13
1..2
# nesting
    1..2
    ok 1 - true is ok
    ok 2 - doag is also okay
ok 1 - nesting
ok 2 - second

then the child stream will be parsed and events will be raised on the childParser object.

Since TAP streams with child tests should follow child test sets with a pass or fail assert based on the child test's results, failing to handle child tests should always result in the same end result. However, additional information from those child tests will obviously be lost.

p.on('extra', function (extra) {})

All other lines will trigger an 'extra' event with the line text.

install

With npm do:

npm install tap-parser

You can use browserify to require('tap-parser') in the browser.

license

MIT