refactor tests to use fake timers

lib/locallock.js

@@ -1,55 +1,62 @@
 var _ = require('lodash');
 var $ = require('preconditions').singleton();
-var locks = {};
 
 function Lock() {
+  this.tasks = {};
+};
 
+Lock.prototype._release = function(token, task) {
+  if (!task.running) return;
+  task.running = false;
+  this.tasks[token] = _.without(this.tasks[token], task);
+  this._runOne(token);
 };
 
 Lock.prototype._runOne = function(token) {
   var self = this;
 
-  var item = _.first(locks[token]);
-  if (!item || item.started) return;
+  if (_.any(self.tasks[token], {
+    running: true
+  })) return;
+
+  var task = _.first(self.tasks[token]);
+  if (!task) return;
 
-  item.started = true;
-  if (item.maxRunningTime > 0) {
+  task.running = true;
+
+  if (task.timeout > 0) {
     setTimeout(function() {
-      var it = _.first(locks[token]);
-      if (it != item) return;
-      locks[token].shift();
-      self._runOne(token);
-    }, item.maxRunningTime);
+      self._release(token, task);
+    }, task.timeout);
   }
 
-  item.fn(null, function() {
-    locks[token].shift();
-    self._runOne(token);
+  task.fn(null, function() {
+    self._release(token, task);
   });
 };
 
-Lock.prototype.locked = function(token, wait, max, task) {
+Lock.prototype.locked = function(token, wait, max, userTask) {
   var self = this;
 
-  if (_.isUndefined(locks[token])) {
-    locks[token] = [];
+  if (_.isUndefined(self.tasks[token])) {
+    self.tasks[token] = [];
   }
 
-  var item = {
-    maxRunningTime: max,
-    started: false,
-    fn: task,
+  var task = {
+    timeout: max,
+    running: false,
+    fn: userTask,
   };
-  locks[token].push(item);
+  self.tasks[token].push(task);
 
   if (wait > 0) {
     setTimeout(function() {
-      var it = _.find(locks[token], item);
-      if (!it || it.started) return;
-      locks[token] = _.without(locks[token], it);
-      it.fn(new Error('Could not acquire lock ' + token));
+      if (task.running || !_.contains(self.tasks[token], task)) return;
+      self.tasks[token] = _.without(self.tasks[token], task);
+      task.fn(new Error('Could not acquire lock ' + token));
     }, wait);
   }
+
   self._runOne(token);
 };
 

test/locallock.js

@@ -10,9 +10,13 @@ var Lock = require('../lib/locallock');
 describe('Local locks', function() {
   var lock;
   beforeEach(function() {
+    this.clock = sinon.useFakeTimers();
     lock = new Lock();
   });
-  it('should lock tasks using the same token', function(done) {
+  afterEach(function() {
+    this.clock.restore();
+  });
+  it('should lock tasks using the same token', function() {
     var a = false,
       b = false;
     lock.locked('123', 0, 0, function(err, release) {
@@ -27,17 +31,13 @@ describe('Local locks', function() {
         release();
       });
     });
-    setTimeout(function() {
-      a.should.equal(true);
-      b.should.equal(false);
-    }, 1);
-    setTimeout(function() {
-      a.should.equal(true);
-      b.should.equal(true);
-      done();
-    }, 8);
+    a.should.equal(true);
+    b.should.equal(false);
+    this.clock.tick(10);
+    a.should.equal(true);
+    b.should.equal(true);
   });
-  it('should not lock tasks using different tokens', function(done) {
+  it('should not lock tasks using different tokens', function() {
     var i = 0;
     lock.locked('123', 0, 0, function(err, release) {
       should.not.exist(err);
@@ -51,12 +51,9 @@ describe('Local locks', function() {
         release();
       });
     });
-    setTimeout(function() {
-      i.should.equal(2);
-      done();
-    }, 1);
+    i.should.equal(2);
   });
-  it('should return error if unable to acquire lock', function(done) {
+  it('should return error if unable to acquire lock', function() {
     lock.locked('123', 0, 0, function(err, release) {
       should.not.exist(err);
       setTimeout(function() {
@@ -65,24 +62,50 @@ describe('Local locks', function() {
       lock.locked('123', 1, 0, function(err, release) {
         should.exist(err);
         err.toString().should.contain('Could not acquire lock 123');
-        done();
       });
     });
+    this.clock.tick(2);
   });
-  it('should release lock if acquired for a long time', function(done) {
+  it('should release lock if acquired for a long time', function() {
     var i = 0;
     lock.locked('123', 0, 3, function(err, release) {
       should.not.exist(err);
       i++;
-      lock.locked('123', 15, 0, function(err, release) {
+      lock.locked('123', 20, 0, function(err, release) {
         should.not.exist(err);
         i++;
+        release();
+      });
+    });
+    i.should.equal(1);
+    this.clock.tick(1);
+    i.should.equal(1);
+    this.clock.tick(10);
+    i.should.equal(2);
+  });
+  it('should only release one pending task on lock timeout', function() {
+    var i = 0;
+    lock.locked('123', 0, 3, function(err, release) {
+      should.not.exist(err);
+      i++;
+      lock.locked('123', 5, 0, function(err, release) {
+        should.not.exist(err);
+        i++;
+        setTimeout(function() {
+          release();
+        }, 5);
+      });
+      lock.locked('123', 20, 0, function(err, release) {
+        should.not.exist(err);
+        i++;
+        release();
       });
     });
-    setTimeout(function() {
-      i.should.equal(2);
-      done();
-    }, 10);
+    i.should.equal(1);
+    this.clock.tick(4);
+    i.should.equal(2)
+    this.clock.tick(7);
+    i.should.equal(3)
   });
 
 });