gajus / require-new

Requires a new module object.

DEPRECATED

Deprecated in favour of require-uncached.

For deprecation reason, see sindresorhus/import-fresh#4.

tl;dr; avoiding duplication of effort in the open-source world.

require-new

Modules are cached after the first time they are loaded. This means (among other things) that every call to require('foo') will get exactly the same object returned, if it would resolve to the same file.

– http://nodejs.org/api/modules.html#modules_caching

require-new requires a new module object.

require-new does not affect the state or behavior of require method.

require-new has been designed to be used for module testing.

Usage

Load require-new module and use it to load a module just as you would with require:

var requireNew = require('require-new'),
    myModule = requireNew('my-module');

Example

If you have a module rand.js:

module.exports = Math.random();

Then requiring this module several times will result in the same response:

require('./rand.js'); // 0.697190385311842
require('./rand.js'); // 0.697190385311842

Modules are cached in a require.cache object when they are required.

require-new deletes the key value from the require.cache object associated with the module you are requesting, making the module reload:

requireNew('./rand.js'); // 0.2123227424453944
requireNew('./rand.js'); // 0.5403654584661126

It then restores the state of the require.cache object to ensure that it does not affect the behavior of require:

require('./rand.js'); // 0.48205413995310664
requireNew('./rand.js'); // 0.12475096038542688
requireNew('./rand.js'); // 0.2615479789674282
require('./rand.js'); // 0.48205413995310664

Alternative Design

You can export a function and call that function. This will make the module execute code multiple times.

module.exports = function () {
    return Math.random();
};

require('rand.js')(); // 0.561616780469194
require('rand.js')(); // 0.6468832329846919

See discussion on Stack Overflow to consider the pros and cons.

Download

Download using NPM:

npm install require-new

require-new's Issues

Use ESHint

Remove "jshint" dev dependency from package.json and the gulp task.

sh:

npm install gulp-eslint --save-dev

gulpfile.js:

var eslint = require('gulp-eslint');

gulp.task('lint', function () {
    return gulp
        .src(['./src/*.js', './src/cinemas/*/*.js', './tests/*.js'])
        .pipe(eslint())
        .pipe(eslint.format())
        .pipe(eslint.failOnError());
});

.eslintrc:

{
    "rules": {
        "no-console": 0,
        "no-extra-parens": 2,
        "no-reserved-keys": 2,
        "no-eq-null": 2,
        "no-extend-native": 2,
        "no-process-env": 2,
        "no-self-compare": 2,
        "no-void": 2,
        "no-warning-comments": [1, { "terms": ["todo", "@toto"], "location": "start" }],
        "vars-on-top": 2,
        "wrap-iife": [2, "inside"],
        "global-strict": [2, "always"],
        "new-cap": 0,
        "no-shadow": 0,
        "no-mixed-requires": 0,
        "no-new-require": 2,
        "brace-style": [2, "1tbs"],
        "comma-style": [2, "last"],
        "func-style": [2, "expression"],
        "no-inline-comments": 2,
        "no-lonely-if": 2,
        "no-multiple-empty-lines": 2,
        "no-nested-ternary": 2,
        "one-var": 2,
        "operator-assignment": [2, "always"],
        "padded-blocks": [2, "never"],
        "quote-props": [2, "as-needed"],
        "quotes": [2, "single"],
        "space-after-keywords": [2, "always"],
        "space-before-blocks": [2, "always"],
        "space-in-brackets": [2, "never"],
        "space-in-parens": [2, "never"],
        "space-unary-ops": [2, { "words": true, "nonwords": false }],
        "spaced-line-comment": [2, "always"],
    },
    "env":{
        "mocha": true,
        "node": true
    }
}

resolve path incorrectly in terminal mode

I didn't try it in code, but I tried it in node terminal.

requireNew('./test') lead to the error:

  Error: Cannot find module '././test'
      at Function.Module._resolveFilename (module.js:336:15)
      at Function.require.resolve (module.js:388:19)
      at requireNew (/Users/zhaoyao-code/workspace/ydcy/pj-b/server/node_modules/require-new/src/require-new.js:21:26)
      at repl:1:1
      at REPLServer.defaultEval (repl.js:132:27)
      at bound (domain.js:254:14)
      at REPLServer.runBound [as eval] (domain.js:267:12)
      at REPLServer.<anonymous> (repl.js:279:12)
      at REPLServer.emit (events.js:107:17)
      at REPLServer.Interface._onLine (readline.js:214:10)