Merge pull request #452 from edi9999/throttle

changed --delay option: it now works like a throttle instead of with setTimeout

lib/monitor/watch.js

@@ -8,8 +8,8 @@ var fs = require('fs'),
     config = require('../config'),
     childProcess = require('child_process'),
     exec = childProcess.exec,
-    restartTimer = null,
     watched = [],
+    throttleRestartBus,
     watchers = [];
 
 var changeFunction = function () {
@@ -195,6 +195,51 @@ function ignoredFileTypesForFind(dir) {
   return ' \\( ' + paths.join(' -or ') + ' \\) -or ';
 }
 
+// Inspired by http://underscorejs.org/docs/underscore.html
+function throttle(func, wait, options) {
+  var context, args, result;
+  var timeout = null;
+  var previous = 0;
+  if (!options) options = {};
+  var later = function() {
+    previous = options.leading === false ? 0 : new Date().getTime();
+    timeout = null;
+    result = func.apply(context, args);
+    if (!timeout) context = args = null;
+  };
+  return function() {
+    var now = new Date().getTime();
+    if (!previous && options.leading === false) previous = new Date().getTime();
+    var remaining = wait - (now - previous);
+    context = this;
+    args = arguments;
+    if (remaining <= 0 || remaining > wait) {
+      clearTimeout(timeout);
+      timeout = null;
+      previous = now;
+      result = func.apply(context, args);
+      if (!timeout) context = args = null;
+    } else if (!timeout && options.trailing !== false) {
+      timeout = setTimeout(later, remaining);
+    }
+    return result;
+  };
+}
+
+function restartBus(matched) {
+  utils.log.status('restarting due to changes...');
+  matched.result.map(function (file) {
+    utils.log.detail(path.relative(process.cwd(), file));
+  });
+
+  if (config.options.verbose) {
+    utils.log._log('');
+  }
+
+  bus.emit('restart', matched.result);
+}
+
+
 function filterAndRestart(files) {
   if (files.length) {
     if (utils.isWindows) {
@@ -217,23 +262,15 @@ function filterAndRestart(files) {
     config.lastStarted = Date.now();
 
     if (matched.result.length) {
-      if (restartTimer !== null) {
-        clearTimeout(restartTimer);
-      }
-      restartTimer = setTimeout(function () {
-        utils.log.status('restarting due to changes...');
-        matched.result.map(function (file) {
-          utils.log.detail(path.relative(process.cwd(), file));
-        });
-
-        if (config.options.verbose) {
-          utils.log._log('');
+      if (config.options.delay > 0) {
+        if (throttleRestartBus === undefined) {
+          throttleRestartBus = throttle(restartBus, config.options.delay, {trailing:false});
         }
-
-        bus.emit('restart', matched.result);
-
-      }, config.options.delay);
-      return;
+        return throttleRestartBus(matched);
+      }
+      else {
+        return restartBus(matched);
+      }
     }
   }
 

test/fork/watch-restart.test.js

@@ -5,7 +5,7 @@ var assert = require('assert'),
     utils = require('../utils'),
     colour = require('../../lib/utils/colour'),
     appjs = utils.appjs,
-    appcoffee = utils.appcoffee,
+    // appcoffee = utils.appcoffee,
     run = utils.run,
     cleanup = utils.cleanup,
     path = require('path'),
@@ -86,6 +86,41 @@ describe('nodemon fork child restart', function () {
     });
   });
 
+  it('should happen only once if delay option is set', function (done) {
+    var restartCount = 0;
+    fs.writeFileSync(tmpjs, 'true;');
+
+    var p = run('--ext js --delay 1' + appjs, {
+      error: function (data) {
+        p.send('quit');
+        cleanup(p, done, new Error(data));
+      }
+    });
+
+    p.on('message', function (event) {
+      if (event.type === 'start') {
+        setTimeout(function () {
+          touch.sync(tmpjs);
+        }, 200);
+        setTimeout(function () {
+          touch.sync(tmpjs);
+        }, 400);
+      } else if (event.type === 'restart') {
+        restartCount++;
+        setTimeout(function () {
+          if (restartCount===1) {
+            assert(true, 'nodemon restarted once');
+            cleanup(p, done);
+          }
+          else {
+            p.send('quit');
+            cleanup(p, done, new Error('nodemon started more than once'));
+          }
+        }, 1500);
+      }
+    });
+  });
+
   it('should happen when monitoring multiple extensions', function (done) {
     fs.writeFileSync(tmpjs, 'true;');
     fs.writeFileSync(tmpmd, '# true');