add: Stat polling support while fs.watch doesn't work.

Add a new cli option: -g --polling [SPAN]

    If state polling mode is enabled, use it.
    Else use the native api.

    This is useful while watching remote directory.
    Such as the `fs.watch` won't catch the SMB server's file change event.

lib/coffee-script/command.js

@@ -38,7 +38,7 @@
 
   BANNER = 'Usage: coffee [options] path/to/script.coffee -- [args]\n\nIf called without options, `coffee` will run your script.';
 
-  SWITCHES = [['-b', '--bare', 'compile without a top-level function wrapper'], ['-c', '--compile', 'compile to JavaScript and save as .js files'], ['-e', '--eval', 'pass a string from the command line as input'], ['-h', '--help', 'display this help message'], ['-i', '--interactive', 'run an interactive CoffeeScript REPL'], ['-j', '--join [FILE]', 'concatenate the source CoffeeScript before compiling'], ['-m', '--map', 'generate source map and save as .map files'], ['-n', '--nodes', 'print out the parse tree that the parser produces'], ['--nodejs [ARGS]', 'pass options directly to the "node" binary'], ['--no-header', 'suppress the "Generated by" header'], ['-o', '--output [DIR]', 'set the output directory for compiled JavaScript'], ['-p', '--print', 'print out the compiled JavaScript'], ['-s', '--stdio', 'listen for and compile scripts over stdio'], ['-l', '--literate', 'treat stdio as literate style coffee-script'], ['-t', '--tokens', 'print out the tokens that the lexer/rewriter produce'], ['-v', '--version', 'display the version number'], ['-w', '--watch', 'watch scripts for changes and rerun commands']];
+  SWITCHES = [['-b', '--bare', 'compile without a top-level function wrapper'], ['-c', '--compile', 'compile to JavaScript and save as .js files'], ['-e', '--eval', 'pass a string from the command line as input'], ['-h', '--help', 'display this help message'], ['-i', '--interactive', 'run an interactive CoffeeScript REPL'], ['-j', '--join [FILE]', 'concatenate the source CoffeeScript before compiling'], ['-m', '--map', 'generate source map and save as .map files'], ['-n', '--nodes', 'print out the parse tree that the parser produces'], ['--nodejs [ARGS]', 'pass options directly to the "node" binary'], ['--no-header', 'suppress the "Generated by" header'], ['-o', '--output [DIR]', 'set the output directory for compiled JavaScript'], ['-p', '--print', 'print out the compiled JavaScript'], ['-s', '--stdio', 'listen for and compile scripts over stdio'], ['-l', '--literate', 'treat stdio as literate style coffee-script'], ['-t', '--tokens', 'print out the tokens that the lexer/rewriter produce'], ['-v', '--version', 'display the version number'], ['-w', '--watch', 'watch scripts for changes and rerun commands'], ['-g', '--polling [SPAN]', 'use the state polling watch mode']];
 
   opts = {};
 
@@ -283,24 +283,37 @@
       });
     };
     try {
-      watcher = fs.watch(source, compile);
+      if (opts.polling) {
+        fs.watchFile(source, {
+          interval: parseInt(opts.polling)
+        }, compile);
+      } else {
+        watcher = fs.watch(source, compile);
+      }
     } catch (_error) {
       e = _error;
       watchErr(e);
     }
     return rewatch = function() {
-      if (watcher != null) {
-        watcher.close();
+      if (opts.polling) {
+        fs.unwatchFile(source);
+        return fs.watchFile(source, {
+          interval: parseInt(opts.polling)
+        }, compile);
+      } else {
+        if (watcher != null) {
+          watcher.close();
+        }
+        return watcher = fs.watch(source, compile);
       }
-      return watcher = fs.watch(source, compile);
     };
   };
 
   watchDir = function(source, base) {
-    var e, readdirTimeout, watcher;
+    var compile, e, readdirTimeout, watcher;
     readdirTimeout = null;
     try {
-      return watcher = fs.watch(source, function() {
+      compile = function() {
         clearTimeout(readdirTimeout);
         return readdirTimeout = wait(25, function() {
           return fs.readdir(source, function(err, files) {
@@ -309,7 +322,11 @@
               if (err.code !== 'ENOENT') {
                 throw err;
               }
-              watcher.close();
+              if (opts.polling) {
+                fs.unwatchFile(source);
+              } else {
+                watcher.close();
+              }
               return unwatchDir(source, base);
             }
             _results = [];
@@ -331,7 +348,14 @@
             return _results;
           });
         });
-      });
+      };
+      if (opts.polling) {
+        return fs.watchFile(source, {
+          interval: parseInt(opts.polling)
+        }, compile);
+      } else {
+        return watcher = fs.watch(source, compile);
+      }
     } catch (_error) {
       e = _error;
       if (e.code !== 'ENOENT') {

src/command.coffee

@@ -51,6 +51,7 @@ SWITCHES = [
   ['-t', '--tokens',          'print out the tokens that the lexer/rewriter produce']
   ['-v', '--version',         'display the version number']
   ['-w', '--watch',           'watch scripts for changes and rerun commands']
+  ['-g', '--polling [SPAN]',  'use the state polling watch mode']
 ]
 
 # Top-level objects shared by all the functions.
@@ -207,26 +208,43 @@ watch = (source, base) ->
           rewatch()
 
   try
-    watcher = fs.watch source, compile
+    # If state polling mode is enabled, use it.
+    # Else use the native api.
+    #
+    # This is useful while watching remote directory.
+    # Such as the `fs.watch` won't catch the SMB server's file change event.
+    if opts.polling
+      fs.watchFile source, { interval: parseInt(opts.polling) }, compile
+    else
+      watcher = fs.watch source, compile
   catch e
     watchErr e
 
   rewatch = ->
-    watcher?.close()
-    watcher = fs.watch source, compile
+    if opts.polling
+      fs.unwatchFile source
+      fs.watchFile source, { interval: parseInt(opts.polling) }, compile
+    else
+      watcher?.close()
+      watcher = fs.watch source, compile
 
 
 # Watch a directory of files for new additions.
 watchDir = (source, base) ->
   readdirTimeout = null
   try
-    watcher = fs.watch source, ->
+    compile = ->
       clearTimeout readdirTimeout
       readdirTimeout = wait 25, ->
         fs.readdir source, (err, files) ->
           if err
             throw err unless err.code is 'ENOENT'
-            watcher.close()
+
+            if opts.polling
+              fs.unwatchFile source
+            else
+              watcher.close()
+
             return unwatchDir source, base
           for file in files when not hidden(file) and not notSources[file]
             file = path.join source, file
@@ -234,6 +252,12 @@ watchDir = (source, base) ->
             sources.push file
             sourceCode.push null
             compilePath file, no, base
+
+    if opts.polling
+      fs.watchFile source, { interval: parseInt(opts.polling) }, compile
+    else
+      watcher = fs.watch source, compile
+
   catch e
     throw e unless e.code is 'ENOENT'