Merge pull request #35 from Obvious/nick-compiler

Change the type signature on Q.resolve, and add Promise.prototype.delay

README.md

@@ -232,6 +232,15 @@ getUrlContent(url1)
 })
 ```
 
+If two arguments are passed, the first will be used as the return value, and the
+second will be the delay in milliseconds.
+
+```javascript
+Q.delay(obj, 20).then(function (result) {
+  console.log(result) // logs `obj` after 20ms
+})
+```
+
 ### `.fcall()` for delaying a function invocation until the next tick:
 ```javascript
 // Assume someFn() is a synchronous 2 argument function you want to delay.

kew.js

@@ -64,7 +64,7 @@ Promise.prototype.getContext = function () {
 /**
  * Resolve this promise with a specified value
  *
- * @param {*} data
+ * @param {*=} data
  */
 Promise.prototype.resolve = function (data) {
   if (this._error || this._hasData) throw new Error("Unable to resolve or reject the same promise twice")
@@ -613,18 +613,41 @@ function defer() {
 /**
  * Return a promise which will wait a specified number of ms to resolve
  *
- * @param {number} delayMs
- * @param {*} returnVal
- * @return {!Promise} returns returnVal
+ * @param {*} delayMsOrVal A delay (in ms) if this takes one argument, or ther
+ *     return value if it takes two.
+ * @param {number=} opt_delayMs
+ * @return {!Promise}
  */
-function delay(delayMs, returnVal) {
+function delay(delayMsOrVal, opt_delayMs) {
+  var returnVal = undefined
+  var delayMs = delayMsOrVal
+  if (typeof opt_delayMs != 'undefined') {
+    delayMs = opt_delayMs
+    returnVal = delayMsOrVal
+  }
+
+  if (typeof delayMs != 'number') {
+    throw new Error('Bad delay value ' + delayMs)
+  }
+
   var defer = new Promise()
   setTimeout(function onDelay() {
     defer.resolve(returnVal)
   }, delayMs)
   return defer
 }
 
+/**
+ * Returns a promise that has the same result as `this`, but fulfilled
+ * after at least ms milliseconds
+ * @param {number} ms
+ */
+Promise.prototype.delay = function (ms) {
+  return this.then(function (val) {
+    return delay(val, ms)
+  })
+}
+
 /**
  * Return a promise which will evaluate the function fn in a future turn with
  * the provided args

package.json

@@ -1,7 +1,7 @@
 {
   "name": "kew",
   "description": "a lightweight promise library for node",
-  "version": "0.3.4",
+  "version": "0.4.0",
   "homepage": "https://github.com/Obvious/kew",
   "authors": [
     "Jeremy Stanley <[email protected]> (https://github.com/azulus)",
@@ -22,7 +22,7 @@
   "devDependencies": {
     "q": "0.9.7",
     "nodeunit": "0.8.1",
-    "closure-npc": "0.0.12"
+    "closure-npc": "0.1.3"
   },
   "scripts": {
     "test": "nodeunit test && closure-npc ./test/closure_test.js --jscomp_error=checkTypes"

test/chain.js

@@ -394,7 +394,7 @@ exports.testTimeout = function(test) {
 }
 
 exports.testNotTimeout = function(test) {
-  var promise = Q.delay(40, 'expected data').timeout(45, 'Timeout message')
+  var promise = Q.delay('expected data', 40).timeout(45, 'Timeout message')
   promise.then(function (data) {
     test.equals('expected data', data, 'The data should be the data from the original promise')
   })
@@ -414,3 +414,15 @@ exports.testNotTimeoutButReject = function(test) {
   })
   .fin(test.done)
 }
+
+exports.testDelay = function (test) {
+  var timePassed = false
+  setTimeout(function () {
+    timePassed = true
+  }, 10)
+  Q.resolve('expected').delay(20).then(function (result) {
+    test.equal('expected', result)
+    test.ok(timePassed)
+    test.done()
+  })
+}

test/static.js

@@ -163,7 +163,9 @@ exports.testDelay = function (test) {
   var startTime = Date.now()
 
   Q.resolve(val)
-    .then(Q.delay.bind(Q, 1000))
+    .then(function (v) {
+      return Q.delay(v, 1000)
+    })
     .then(function (returnVal) {
       test.equal(returnVal, val, "Val should be passed through")
       test.equal(Date.now() - startTime >= 1000, true, "Should have waited a second")