add node_modules

node_modules/pend/index.js

@@ -0,0 +1,55 @@
+module.exports = Pend;
+
+function Pend() {
+  this.pending = 0;
+  this.max = Infinity;
+  this.listeners = [];
+  this.waiting = [];
+  this.error = null;
+}
+
+Pend.prototype.go = function(fn) {
+  if (this.pending < this.max) {
+    pendGo(this, fn);
+  } else {
+    this.waiting.push(fn);
+  }
+};
+
+Pend.prototype.wait = function(cb) {
+  if (this.pending === 0) {
+    cb(this.error);
+  } else {
+    this.listeners.push(cb);
+  }
+};
+
+Pend.prototype.hold = function() {
+  return pendHold(this);
+};
+
+function pendHold(self) {
+  self.pending += 1;
+  var called = false;
+  return onCb;
+  function onCb(err) {
+    if (called) throw new Error("callback called twice");
+    called = true;
+    self.error = self.error || err;
+    self.pending -= 1;
+    if (self.waiting.length > 0 && self.pending < self.max) {
+      pendGo(self, self.waiting.shift());
+    } else if (self.pending === 0) {
+      var listeners = self.listeners;
+      self.listeners = [];
+      listeners.forEach(cbListener);
+    }
+  }
+  function cbListener(listener) {
+    listener(self.error);
+  }
+}
+
+function pendGo(self, fn) {
+  fn(pendHold(self));
+}

node_modules/pend/test.js

@@ -0,0 +1,137 @@
+var assert = require('assert');
+var Pend = require('./');
+
+var tests = [
+  {
+    name: "basic",
+    fn: testBasic,
+  },
+  {
+    name: "max",
+    fn: testWithMax,
+  },
+  {
+    name: "callback twice",
+    fn: testCallbackTwice,
+  },
+  {
+    name: "calling wait twice",
+    fn: testCallingWaitTwice,
+  },
+  {
+    name: "hold()",
+    fn: testHoldFn,
+  },
+];
+var testCount = tests.length;
+
+doOneTest();
+
+function doOneTest() {
+  var test = tests.shift();
+  if (!test) {
+    console.log(testCount + " tests passed.");
+    return;
+  }
+  process.stdout.write(test.name + "...");
+  test.fn(function() {
+    process.stdout.write("OK\n");
+    doOneTest();
+  });
+}
+
+function testBasic(cb) {
+  var pend = new Pend();
+  var results = [];
+  pend.go(function(cb) {
+    results.push(1);
+    setTimeout(function() {
+      results.push(3);
+      cb();
+    }, 500);
+  });
+  pend.go(function(cb) {
+    results.push(2);
+    setTimeout(function() {
+      results.push(4);
+      cb();
+    }, 1000);
+  });
+  pend.wait(function(err) {
+    assert.deepEqual(results, [1,2,3,4]);
+    cb();
+  });
+  assert.deepEqual(results, [1, 2]);
+}
+
+function testWithMax(cb) {
+  var pend = new Pend();
+  var results = [];
+  pend.max = 2;
+  pend.go(function(cb) {
+    results.push('a');
+    setTimeout(function() {
+      results.push(1);
+      cb();
+    }, 500);
+  });
+  pend.go(function(cb) {
+    results.push('b');
+    setTimeout(function() {
+      results.push(1);
+      cb();
+    }, 500);
+  });
+  pend.go(function(cb) {
+    results.push('c');
+    setTimeout(function() {
+      results.push(2);
+      cb();
+    }, 100);
+  });
+  pend.wait(function(err) {
+    assert.deepEqual(results, ['a', 'b', 1, 'c', 1, 2]);
+    cb();
+  });
+  assert.deepEqual(results, ['a', 'b']);
+}
+
+function testCallbackTwice(cb) {
+  var pend = new Pend();
+  pend.go(function(cb) {
+    setTimeout(cb, 100);
+  });
+  pend.go(function(cb) {
+    cb();
+    assert.throws(cb, /callback called twice/);
+  });
+  pend.wait(cb);
+}
+
+function testCallingWaitTwice(cb) {
+  var pend = new Pend();
+  pend.go(function(cb) {
+    setTimeout(cb, 100);
+  });
+  pend.wait(function() {
+    pend.go(function(cb) {
+      setTimeout(cb, 50);
+    });
+    pend.go(function(cb) {
+      setTimeout(cb, 10);
+    });
+    pend.go(function(cb) {
+      setTimeout(cb, 20);
+    });
+    pend.wait(cb);
+  });
+}
+
+function testHoldFn(cb) {
+  var pend = new Pend();
+  setTimeout(pend.hold(), 100);
+  pend.go(function(cb) {
+    cb();
+  });
+  pend.wait(cb);
+}