defrex / js-depends

Stop JavaScript dependancy accidents today.

Depends

Stop JavaScript dependancy accidents today.

Install

npm -g install depends

Usage

At the top of a given js file, you can put dep.provide and dep.require. The names (strings) passed into these functions can be whatever you want. Module names makes sense.

dep.provide('lib1');

window.lib1 = 'awesome';

. . .

dep.require('lib1');
dep.provide('lib2');

if (window.lib1 != 'awesome') throw('a fit')

. . .

dep.require('lib1');
dep.require('lib2');

if (window.lib1 != 'awesome') throw('a fit')

This style is largely inspired to Google Closure's goog.provide and goog.require, only without the investment of using Closure Library.

Once that is in place, you'll need to run depends over your js directory.

depends ./jsDirectory

This will output the list of js files, sorted to resolve all the dependencies. You can do with that what you will.

In development I generally shell out to depends and wrap the output in <script> tags before stuffing it in my base html template. For production the output can be piped into some other post-processor, like uglify. For example,

depends -i ./jsDirectory | xargs uglifyjs > min.js

Client-side

client/depends.js is a small client side lib. It provides definitions for dep.require and dep.provide at runtime.

dep.provide will ensure that the namespace exists, non-destructively assigning all the values (split by .) in the chain to {}.

dep.require will throw a warning if you're requiring something that isn't loaded. Normally this would never happen.

Alternately, put this noop somewhere before loading your code,

window.dep = {require: function(){}, provide: function(){}};

Node.js lib

depends is also usable as a node.js library.

var depends = require('depends');

depends.manage(directory, function(error, files){
  files.map // object {module: filename}
  files.sorted // array [module, module..] in dep order
  files.output // array [filename, filename..] in dep order
});

Development

Build the client,

./node_modules/.bin/coffee -cbp src/client.coffee > client/depends.js
./node_modules/.bin/uglifyjs client/depends.js > client/depends.min.js

Run the tests,

./node_modules/.bin/mocha --compilers coffee:coffee-script