From 3b4c61b9c1d550f72f342f6dbbfabbfc1b16525e Mon Sep 17 00:00:00 2001
From: nate kidwell <nate@ludicast.com>
Date: Mon, 19 Nov 2012 00:11:19 -0500
Subject: [PATCH] added branchOn combinator

---
 lib/method-combinators.coffee       | 11 +++++++++++
 lib/method-combinators.js           | 16 +++++++++++++++-
 spec/method-combinators.spec.coffee | 17 +++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/lib/method-combinators.coffee b/lib/method-combinators.coffee
index 8f712db..12ecf94 100644
--- a/lib/method-combinators.coffee
+++ b/lib/method-combinators.coffee
@@ -37,6 +37,17 @@ this.provided =
 
 # ## Extras
 
+# Allows branching between functions depending on the result of a test function
+
+this.branchOn = 
+  (predicate)->
+    ({failure, success})->
+      ->
+        if predicate.apply(this, arguments)
+          success?.apply(this, arguments)
+        else
+          failure?.apply(this, arguments)
+
 # If the method thows an error, retry it again a certain number of times.
 # e.g. `retry(3) -> # doSomething as many as four times`
 this.retry =
diff --git a/lib/method-combinators.js b/lib/method-combinators.js
index 74b0d8f..119be2b 100644
--- a/lib/method-combinators.js
+++ b/lib/method-combinators.js
@@ -1,4 +1,4 @@
-// Generated by CoffeeScript 1.3.1
+// Generated by CoffeeScript 1.4.0
 (function() {
   var __slice = [].slice;
 
@@ -47,6 +47,20 @@
     };
   };
 
+  this.branchOn = function(predicate) {
+    return function(_arg) {
+      var failure, success;
+      failure = _arg.failure, success = _arg.success;
+      return function() {
+        if (predicate.apply(this, arguments)) {
+          return success != null ? success.apply(this, arguments) : void 0;
+        } else {
+          return failure != null ? failure.apply(this, arguments) : void 0;
+        }
+      };
+    };
+  };
+
   this.retry = function(times) {
     return function(base) {
       return function() {
diff --git a/spec/method-combinators.spec.coffee b/spec/method-combinators.spec.coffee
index 17d0221..e418f22 100644
--- a/spec/method-combinators.spec.coffee
+++ b/spec/method-combinators.spec.coffee
@@ -168,6 +168,23 @@ describe "Method Combinators", ->
 
       expect(eg.foo).toBe('foo')
 
+  describe "branchOn", ->
+
+    it "runs success/fail function on resulting test", ->
+
+      decorator = C.branchOn (value)->
+        value
+
+      class BranchOnClazz
+        getValue:
+          decorator
+            success: -> "success"
+            failure: -> "failure"
+
+      eg = new BranchOnClazz()
+      expect(eg.getValue(true)).toBe('success')
+      expect(eg.getValue(false)).toBe('failure')
+
   describe "retry", ->
 
     describe 'times < 0', ->