Separate Promise implementation from polyfilling

docs/change-log.md

@@ -47,6 +47,13 @@
 
 ---
 
+### v1.1.7
+
+- Promise polyfill implementation separated from polyfilling logic.
+- `PromisePolyfill` is now available on the exported/global `m`.
+
+---
+
 ### v1.1.6
 
 - core: render() function can no longer prevent from changing `document.activeElement` in lifecycle hooks ([#1988](https://github.com/MithrilJS/mithril.js/pull/1988), [@purplecode](https://github.com/purplecode))

docs/promise.md

@@ -26,6 +26,8 @@ A [ES6 Promise](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/G
 
 A Promise is a mechanism for working with asynchronous computations.
 
+Mithril provides a polyfill when the environment does not support Promises. The polyfill can also be referenced specifically via `m.PromisePolyfill`.
+
 ---
 
 ### Signature

index.js

@@ -17,5 +17,6 @@ m.parseQueryString = require("./querystring/parse")
 m.buildQueryString = require("./querystring/build")
 m.version = "bleeding-edge"
 m.vnode = require("./render/vnode")
+m.PromisePolyfill = require("./promise/polyfill")
 
 module.exports = m

promise/polyfill.js

@@ -0,0 +1,98 @@
+"use strict"
+/** @constructor */
+var PromisePolyfill = function(executor) {
+	if (!(this instanceof PromisePolyfill)) throw new Error("Promise must be called with `new`")
+	if (typeof executor !== "function") throw new TypeError("executor must be a function")
+
+	var self = this, resolvers = [], rejectors = [], resolveCurrent = handler(resolvers, true), rejectCurrent = handler(rejectors, false)
+	var instance = self._instance = {resolvers: resolvers, rejectors: rejectors}
+	var callAsync = typeof setImmediate === "function" ? setImmediate : setTimeout
+	function handler(list, shouldAbsorb) {
+		return function execute(value) {
+			var then
+			try {
+				if (shouldAbsorb && value != null && (typeof value === "object" || typeof value === "function") && typeof (then = value.then) === "function") {
+					if (value === self) throw new TypeError("Promise can't be resolved w/ itself")
+					executeOnce(then.bind(value))
+				}
+				else {
+					callAsync(function() {
+						if (!shouldAbsorb && list.length === 0) console.error("Possible unhandled promise rejection:", value)
+						for (var i = 0; i < list.length; i++) list[i](value)
+						resolvers.length = 0, rejectors.length = 0
+						instance.state = shouldAbsorb
+						instance.retry = function() {execute(value)}
+					})
+				}
+			}
+			catch (e) {
+				rejectCurrent(e)
+			}
+		}
+	}
+	function executeOnce(then) {
+		var runs = 0
+		function run(fn) {
+			return function(value) {
+				if (runs++ > 0) return
+				fn(value)
+			}
+		}
+		var onerror = run(rejectCurrent)
+		try {then(run(resolveCurrent), onerror)} catch (e) {onerror(e)}
+	}
+
+	executeOnce(executor)
+}
+PromisePolyfill.prototype.then = function(onFulfilled, onRejection) {
+	var self = this, instance = self._instance
+	function handle(callback, list, next, state) {
+		list.push(function(value) {
+			if (typeof callback !== "function") next(value)
+			else try {resolveNext(callback(value))} catch (e) {if (rejectNext) rejectNext(e)}
+		})
+		if (typeof instance.retry === "function" && state === instance.state) instance.retry()
+	}
+	var resolveNext, rejectNext
+	var promise = new PromisePolyfill(function(resolve, reject) {resolveNext = resolve, rejectNext = reject})
+	handle(onFulfilled, instance.resolvers, resolveNext, true), handle(onRejection, instance.rejectors, rejectNext, false)
+	return promise
+}
+PromisePolyfill.prototype.catch = function(onRejection) {
+	return this.then(null, onRejection)
+}
+PromisePolyfill.resolve = function(value) {
+	if (value instanceof PromisePolyfill) return value
+	return new PromisePolyfill(function(resolve) {resolve(value)})
+}
+PromisePolyfill.reject = function(value) {
+	return new PromisePolyfill(function(resolve, reject) {reject(value)})
+}
+PromisePolyfill.all = function(list) {
+	return new PromisePolyfill(function(resolve, reject) {
+		var total = list.length, count = 0, values = []
+		if (list.length === 0) resolve([])
+		else for (var i = 0; i < list.length; i++) {
+			(function(i) {
+				function consume(value) {
+					count++
+					values[i] = value
+					if (count === total) resolve(values)
+				}
+				if (list[i] != null && (typeof list[i] === "object" || typeof list[i] === "function") && typeof list[i].then === "function") {
+					list[i].then(consume, reject)
+				}
+				else consume(list[i])
+			})(i)
+		}
+	})
+}
+PromisePolyfill.race = function(list) {
+	return new PromisePolyfill(function(resolve, reject) {
+		for (var i = 0; i < list.length; i++) {
+			list[i].then(resolve, reject)
+		}
+	})
+}
+
+module.exports = PromisePolyfill

promise/promise.js

@@ -1,99 +1,6 @@
 "use strict"
-/** @constructor */
-var PromisePolyfill = function(executor) {
-	if (!(this instanceof PromisePolyfill)) throw new Error("Promise must be called with `new`")
-	if (typeof executor !== "function") throw new TypeError("executor must be a function")
 
-	var self = this, resolvers = [], rejectors = [], resolveCurrent = handler(resolvers, true), rejectCurrent = handler(rejectors, false)
+var PromisePolyfill = require("./polyfill")
-	var instance = self._instance = {resolvers: resolvers, rejectors: rejectors}
-	var callAsync = typeof setImmediate === "function" ? setImmediate : setTimeout
-	function handler(list, shouldAbsorb) {
-		return function execute(value) {
-			var then
-			try {
-				if (shouldAbsorb && value != null && (typeof value === "object" || typeof value === "function") && typeof (then = value.then) === "function") {
-					if (value === self) throw new TypeError("Promise can't be resolved w/ itself")
-					executeOnce(then.bind(value))
-				}
-				else {
-					callAsync(function() {
-						if (!shouldAbsorb && list.length === 0) console.error("Possible unhandled promise rejection:", value)
-						for (var i = 0; i < list.length; i++) list[i](value)
-						resolvers.length = 0, rejectors.length = 0
-						instance.state = shouldAbsorb
-						instance.retry = function() {execute(value)}
-					})
-				}
-			}
-			catch (e) {
-				rejectCurrent(e)
-			}
-		}
-	}
-	function executeOnce(then) {
-		var runs = 0
-		function run(fn) {
-			return function(value) {
-				if (runs++ > 0) return
-				fn(value)
-			}
-		}
-		var onerror = run(rejectCurrent)
-		try {then(run(resolveCurrent), onerror)} catch (e) {onerror(e)}
-	}
-
-	executeOnce(executor)
-}
-PromisePolyfill.prototype.then = function(onFulfilled, onRejection) {
-	var self = this, instance = self._instance
-	function handle(callback, list, next, state) {
-		list.push(function(value) {
-			if (typeof callback !== "function") next(value)
-			else try {resolveNext(callback(value))} catch (e) {if (rejectNext) rejectNext(e)}
-		})
-		if (typeof instance.retry === "function" && state === instance.state) instance.retry()
-	}
-	var resolveNext, rejectNext
-	var promise = new PromisePolyfill(function(resolve, reject) {resolveNext = resolve, rejectNext = reject})
-	handle(onFulfilled, instance.resolvers, resolveNext, true), handle(onRejection, instance.rejectors, rejectNext, false)
-	return promise
-}
-PromisePolyfill.prototype.catch = function(onRejection) {
-	return this.then(null, onRejection)
-}
-PromisePolyfill.resolve = function(value) {
-	if (value instanceof PromisePolyfill) return value
-	return new PromisePolyfill(function(resolve) {resolve(value)})
-}
-PromisePolyfill.reject = function(value) {
-	return new PromisePolyfill(function(resolve, reject) {reject(value)})
-}
-PromisePolyfill.all = function(list) {
-	return new PromisePolyfill(function(resolve, reject) {
-		var total = list.length, count = 0, values = []
-		if (list.length === 0) resolve([])
-		else for (var i = 0; i < list.length; i++) {
-			(function(i) {
-				function consume(value) {
-					count++
-					values[i] = value
-					if (count === total) resolve(values)
-				}
-				if (list[i] != null && (typeof list[i] === "object" || typeof list[i] === "function") && typeof list[i].then === "function") {
-					list[i].then(consume, reject)
-				}
-				else consume(list[i])
-			})(i)
-		}
-	})
-}
-PromisePolyfill.race = function(list) {
-	return new PromisePolyfill(function(resolve, reject) {
-		for (var i = 0; i < list.length; i++) {
-			list[i].then(resolve, reject)
-		}
-	})
-}
 
 if (typeof window !== "undefined") {
 	if (typeof window.Promise === "undefined") window.Promise = PromisePolyfill

promise/tests/test-promise.js

@@ -2,7 +2,7 @@
 
 var o = require("../../ospec/ospec")
 var callAsync = require("../../test-utils/callAsync")
-var Promise = require("../../promise/promise")
+var Promise = require("../../promise/polyfill")
 
 o.spec("promise", function() {
 	o.spec("constructor", function() {