--runonce flag added; same as --initial but process exits after initial run

index.js

@@ -25,6 +25,7 @@ var defaultOpts = {
     verbose: false,
     silent: false,
     initial: false,
+    runonce: false,
     command: null
 };
 
@@ -83,6 +84,11 @@ var argv = require('yargs')
         default: defaultOpts.initial,
         type: 'boolean'
     })
+    .option('runonce', {
+        describe: 'When set, command is initially run once and the process is terminated afterwards',
+        default: defaultOpts.runonce,
+        type: 'boolean'
+    })
     .option('p', {
         alias: 'polling',
         describe: 'Whether to use fs.watchFile(backed by polling) instead of ' +
@@ -140,7 +146,7 @@ function startWatching(opts) {
     var watcher = chokidar.watch(opts.patterns, chokidarOpts);
 
     var throttledRun = _.throttle(run, opts.throttle);
-    var debouncedRun = _.debounce(throttledRun, opts.debounce);
+    var debouncedRun = run; // process all requests during initial stage (runonce or initial)
     watcher.on('all', function(event, path) {
         var description = EVENT_DESCRIPTIONS[event] + ':';
 
@@ -172,6 +178,8 @@ function startWatching(opts) {
         if (!opts.silent) {
             console.error('Watching', '"' + list + '" ..');
         }
+        // debounce after initial stage
+        debouncedRun = _.debounce(throttledRun, opts.debounce);
     });
 }
 
@@ -180,11 +188,12 @@ function createChokidarOpts(opts) {
     opts.ignore = _resolveIgnoreOpt(opts.ignore);
 
     var chokidarOpts = {
+        persistent: !opts.runonce,
         followSymlinks: opts.followSymlinks,
         usePolling: opts.polling,
         interval: opts.pollInterval,
         binaryInterval: opts.pollIntervalBinary,
-        ignoreInitial: !opts.initial
+        ignoreInitial: !opts.runonce && !opts.initial
     };
     if (opts.ignore) chokidarOpts.ignored = opts.ignore;