Added tests for recent bugs

src/rules/rule.coffee

@@ -5,7 +5,7 @@ module.exports =
   # @param dataStructure [Object] The super type data structure
   # @param memberTypeSection [Object] Member Type Section to be copied into
   copyMembers: (dataStructure, memberTypeSection) ->
-    return if not dataStructure
+    return if not dataStructure or not memberTypeSection
 
     for section in dataStructure.sections
       if section['class'] is 'memberType'

test/unit/drafter-test.coffee

@@ -23,3 +23,49 @@ describe 'Drafter Class', ->
       assert.deepEqual result.ast, require '../fixtures/dataStructures.ast.json'
 
       done()
+
+  it 'parses correctly when super type of a member is not found', (done) ->
+    drafter = new Drafter
+
+    blueprint = '''
+    # Polls [/]
+
+    + Attributes
+        + owner (Person)
+    '''
+
+    drafter.make blueprint, (error, result) ->
+      assert.isNull error
+      assert.ok result.ast
+      done()
+
+  it 'parses correctly when super type of a type is not found', (done) ->
+    drafter = new Drafter
+
+    blueprint = '''
+    # Polls [/]
+    ## Get a Poll [GET]
+
+    + Attributes (Person)
+        + id
+    '''
+
+    drafter.make blueprint, (error, result) ->
+      assert.isNull error
+      assert.ok result.ast
+      done()
+
+  it 'parses correctly when named type in a mixin is not found', (done) ->
+    drafter = new Drafter
+
+    blueprint = '''
+    # Polls [/]
+
+    + Attributes
+        + Include Person
+    '''
+
+    drafter.make blueprint, (error, result) ->
+      assert.isNull error
+      assert.ok result.ast
+      done()