Fix the MakeFunction component

components/MakeFunction.coffee

@@ -22,31 +22,42 @@ exports.getComponent = ->
   c.outPorts.add 'error',
     datatype: 'object'
 
+  prepareFunction = (func, callback) ->
+    if typeof func is 'function'
+      callback null, func
+      return
+    try
+      newFunc = Function 'x', func
+    catch e
+      callback e
+      return
+    callback null, newFunc
+
   c.process (input, output) ->
-    if input.has 'function'
-      func = input.getData 'function'
-      unless typeof func is 'function'
+    return if input.attached('in').length and not input.hasData 'in'
+    if input.hasData 'function', 'in'
+      # Both function and input data
+      prepareFunction input.getData('function'), (err, func) ->
+        if err
+          output.done e
+          return
+        data = input.getData 'in'
         try
-          func = Function 'x', func
+          result = func data
         catch e
-          output.sendDone e
+          output.done e
           return
-      unless input.has 'in'
         output.sendDone
           function: func
+          out: result
         return
-
-    unless func
-      output.sendDone new Error 'No function defined'
       return
-
-    data = input.getData 'in'
-    try
-      result = func data
-    catch e
-      output.sendDone e
+    return unless input.hasData 'function'
+    prepareFunction input.getData('function'), (err, func) ->
+      if err
+        output.done e
+        return
+      output.sendDone
+        function: func
       return
-
-    output.sendDone
-      function: func
-      out: result
+    return

spec/MakeFunction.coffee

@@ -21,9 +21,7 @@ describe 'MakeFunction component', ->
     loader.load 'core/MakeFunction', (err, instance) ->
       return done err if err
       c = instance
-      ins = noflo.internalSocket.createSocket()
       func = noflo.internalSocket.createSocket()
-      c.inPorts.in.attach ins
       c.inPorts.function.attach func
       done()
   beforeEach ->
@@ -47,15 +45,7 @@ describe 'MakeFunction component', ->
       chai.expect(c.outPorts.out).to.be.an 'object'
       chai.expect(c.outPorts.error).to.be.an 'object'
 
-  describe 'test function', ->
-    it 'without function', (done) ->
-      err.on 'data', (data) ->
-        chai.expect(data).to.be.an 'error'
-        done()
-
-      ins.send 'Foo bar'
-      ins.disconnect()
-
+  describe 'with only function', ->
     it 'wrong function', (done) ->
       err.on 'data', (data) ->
         chai.expect(data).to.be.ok
@@ -72,6 +62,13 @@ describe 'MakeFunction component', ->
         done data
       func.send 'return x*x;'
 
+  describe 'with function and input data', ->
+    before ->
+      ins = noflo.internalSocket.createSocket()
+      c.inPorts.in.attach ins
+    after ->
+      c.inPorts.in.detach ins
+      ins = null
     it 'square function', (done) ->
       out.on 'data', (data) ->
         chai.expect(data).to.equal 81