node package manager


Power Assert feature instrumentor on the fly


Power Assert feature instrumentor on the fly.

espower-loader is a Node.js module loader that enhances target sources on the fly. So you can instrument Power Assert feature without code generation for now.

espower-loader applies espower to target sources on loading them. espower manipulates assertion expression (JavaScript Code) in the form of ECMAScript AST defined in The ESTree Spec (formerly known as Mozilla SpiderMonkey Parser API), to instrument power-assert feature into the code. espower-loader also adjusts line and column number in stack traces by using source-map-support module.

Pull-requests, issue reports and patches are always welcomed. See power-assert project for more documentation.

FYI: You may be interested in intelli-espower-loader to go one step further. With intelli-espower-loader, you don't need to create loader file (like enable-power-assert.js). Just define test directory in package.json wow!

You can instrument power-assert without code generation (e.g. without using grunt-espower,gulp-espower, and so on).

For mocha, Just add --require option.

$ mocha --require ./path/to/enable-power-assert test/some_test_using_powerassert.js

where enable-power-assert.js somewhere in your project is,

    pattern: '{src,test}/**/*.js'

You can specify options for espower module explicitly.

    // directory where match starts with 
    cwd: process.cwd(),
    // glob pattern using minimatch module 
    pattern: '{src,test}/**/*.js',
    // options for espower module 
    espowerOptions: {
        patterns: [
            '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])'

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 espower-source works in any of the unsupported environments, it is purely coincidental and has no bearing on future compatibility. Use at your own risk.


Licensed under the MIT license.