add --dedupe

.gitignore

@@ -1,2 +1,3 @@
 .DS_Store
-node_modules
+node_modules
+npm-debug.log

README.md

@@ -78,12 +78,23 @@ options you can set to tweak its behaviour:
 * `timestamp` – The timestamp format to use for logging restarts. _Default:_ `"HH:MM:ss"`
 * `vm` – Whether to watch files loaded via Node's [VM](http://nodejs.org/docs/latest/api/vm.html) module. _Default:_ `true`
 * `fork` – Whether to hook into [child_process.fork](http://nodejs.org/docs/latest/api/child_process.html#child_process_child_process_fork_modulepath_args_options) (required for [clustered](http://nodejs.org/docs/latest/api/cluster.html) programs). _Default:_ `true`
-* `deps` - How many levels of dependencies should be watched. _Default:_ `1`
+* `deps` – How many levels of dependencies should be watched. _Default:_ `1`
+* `dedupe` – Whether modules should by [dynamically deduped](https://www.npmjs.org/package/dynamic-dedupe). _Default:_ `false`
 
 Upon startup node-dev looks for a `.node-dev.json` file in the user's HOME
 directory. It will also look for a `.node-dev.json` file in the current
 directory which (if present) overwrites the per-user settings.
 
+### Dedupe linked modules
+
+Sometimes you need to make sure that multiple modules get
+_exactly the same instance_ of a common (peer-) dependency. This can usually be
+achieved by running `npm dedupe` – however this doesn't work when you try to
+`npm link` a dependency (which is quite common during development). Therefore
+node-dev provides a `--dedupe` switch that will inject the
+[dynamic-dedupe](https://www.npmjs.org/package/dynamic-dedupe) module into your
+app.
+
 ### Transpilers
 
 You can also use node-dev to run transpiled languages. You can either use a

lib/cfg.js

@@ -16,6 +16,7 @@ module.exports = {
   deps       : c.deps,
   timestamp  : c.timestamp || (c.timestamp !== false && 'HH:MM:ss'),
   clear      : !!c.clear,
+  dedupe     : !!c.dedupe,
   extensions : c.extensions || {
     coffee: "coffee-script/register",
     ls: "LiveScript"

lib/cli.js

@@ -21,7 +21,8 @@ exports.parseOpts = function(args, defaults) {
   else if (option(args, '--no-deps')) deps = 0
 
   return {
-    deps: deps
+    deps: deps,
+    dedupe: option(args, '--dedupe', defaults.dedupe)
   }
 }
 

lib/dedupe.js

@@ -0,0 +1 @@
+require('dynamic-dedupe').activate()

lib/hook.js

@@ -24,11 +24,14 @@ module.exports = function(wrapper, callback) {
     var handlers = require.extensions
     for (var ext in handlers) {
 
-      // Get or create the hook for the extension
-      var hook = hooks[ext] || (hooks[ext] = createHook(ext))
+      // Get or create the hook for the extension ...
+      var hook = hooks[ext]
+
+      // first encounter, create a new hook
+      if (!hook) hook = hooks[ext] = createHook(ext)
 
       if (handlers[ext] !== hook) {
-        origs[ext] = handlers[ext]
+        if (!origs[ext]) origs[ext] = handlers[ext]
         handlers[ext] = hook
       }
     }
@@ -52,7 +55,7 @@ module.exports = function(wrapper, callback) {
       origs[ext](module, filename)
 
       // Make sure the module did not hijack the handler
-      updateHooks()
+      //updateHooks()
     }
   }
 

lib/index.js

@@ -15,6 +15,9 @@ module.exports = function(args) {
   // Parse command line options
   var opts = cli.parseOpts(args, cfg)
 
+  // Run ./dedupe.js as prelaod script
+  if (opts.dedupe) process.env.NODE_DEV_PRELOAD = __dirname + '/dedupe'
+
   // Inject wrap.js into the args array
   cli.injectScript(args, __dirname + '/wrap.js')
 

lib/wrap.js

@@ -11,6 +11,10 @@ process.argv.splice(1, 1)
 // Set NODE_ENV to 'development' unless already set
 if (!process.env.NODE_ENV) process.env.NODE_ENV = 'development'
 
+if (process.env.NODE_DEV_PRELOAD) {
+  require(process.env.NODE_DEV_PRELOAD)
+}
+
 // Listen SIGTERM and exit unless there is another listener
 process.on('SIGTERM', function() {
   if (process.listeners('SIGTERM').length == 1) process.exit(0)

package.json

@@ -27,9 +27,10 @@
     "test": "mocha"
   },
   "dependencies": {
-    "growl": "~1.7.0",
     "dateformat": "~1.0.4-1.2.3",
-    "filewatcher": "~1.1.1"
+    "dynamic-dedupe": "^0.2.0",
+    "filewatcher": "~1.1.1",
+    "growl": "~1.7.0"
   },
   "devDependencies": {
     "mocha": "~1.4.1",