unassertify

unassertify

Browserify transform for unassert: Encourages programming with assertions by providing tools to compile them away.

RELATED MODULES

• unassert: Encourages programming with assertions by providing tools to compile them away.
• babel-plugin-unassert: Babel plugin for unassert
• webpack-unassert-loader: Webpack loader for unassert
• gulp-unassert: Gulp plugin for unassert
• unassert-cli: CLI for unassert

INSTALL

$ npm install --save-dev unassertify

HOW TO USE

via CLI

$ $(npm bin)/browserify -t unassertify /path/to/src/target.js > /path/to/build/target.js

via API

var source = require('vinyl-source-stream');
var browserify = require('browserify');
var glob = require('glob'),

gulp.task('production_build', function() {
    var files = glob.sync('./src/*.js');
    var b = browserify({entries: files});
    b.transform('unassertify');
    return b.bundle()
        .pipe(source('bundle.js'))
        .pipe(gulp.dest('./dist'));
});

EXAMPLE

For given math.js below,

'use strict';

var assert = require('assert');

function add (a, b) {
    console.assert(typeof a === 'number');
    assert(!isNaN(a));
    assert.equal(typeof b, 'number');
    assert.ok(!isNaN(b));
    return a + b;
}

Run browserify with -t unassertify to transform file.

$ $(npm bin)/browserify -t unassertify /path/to/demo/math.js > /path/to/build/math.js

You will see assert calls disappear.

'use strict';
function add(a, b) {
    return a + b;
}

SUPPORTED PATTERNS

Assertion expressions are removed when they match patterns below. In other words, unassertify removes assertion calls that are compatible with Node.js standard assert API (and console.assert).

• assert(value, [message])
• assert.ok(value, [message])
• assert.equal(actual, expected, [message])
• assert.notEqual(actual, expected, [message])
• assert.strictEqual(actual, expected, [message])
• assert.notStrictEqual(actual, expected, [message])
• assert.deepEqual(actual, expected, [message])
• assert.notDeepEqual(actual, expected, [message])
• assert.deepStrictEqual(actual, expected, [message])
• assert.notDeepStrictEqual(actual, expected, [message])
• assert.fail(actual, expected, message, operator)
• assert.throws(block, [error], [message])
• assert.doesNotThrow(block, [message])
• assert.ifError(value)
• console.assert(value, [message])

unassertify also removes assert variable declarations,

• var assert = require("assert")
• var assert = require("power-assert")

and assignments.

• assert = require("assert")
• assert = require("power-assert")

AUTHOR

• Takuto Wada

CONTRIBUTORS

• Renée Kooi

OUR SUPPORT POLICY

We support Node under maintenance. In other words, we stop supporting old Node version when their maintenance ends.

This means that any other environment is not supported.

NOTE: If unassertify works in any of the unsupported environments, it is purely coincidental and has no bearing on future compatibility. Use at your own risk.

LICENSE

Licensed under the MIT license.

Changelog

2.1.1 (2018-04-19)

Performance Improvements

• Skip parsing if file doesn't contain assertions by @goto-bus-stop