Add __ne__ built-in function

In Python 3 __ne__ by default delegates to __eq__ and inverts the
result, but in Python 2 they urge you to define __ne__ when you
define __eq__ for it to work properly [1].There are no implied
relationships among the comparison operators. The truth of x==y
does not imply that x!=y is false. Accordingly, when defining __eq__(),
one should also define __ne__() so that the operators will behave as
expected.
[1]https://docs.python.org/2/reference/datamodel.html#object.__ne_

Change-Id: I52633a8a4b19c5e0c0d7d786f21770496e128c7a

monasca_analytics/banana/grammar/ast.py

@@ -189,6 +189,9 @@ class StringLit(ASTNode):
         return (isinstance(other, StringLit) or isinstance(other, Ident))\
             and self.inner_val() == other.inner_val()
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __str__(self):
         return "StringLit< {} >".format(self.val)
 
@@ -218,6 +221,9 @@ class Ident(ASTNode):
         return (isinstance(other, StringLit) or isinstance(other, Ident))\
             and self.val == other.inner_val()
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __str__(self):
         return "Ident< {} >".format(self.val)
 
@@ -274,6 +280,9 @@ class DotPath(ASTNode):
     def __eq__(self, other):
         return self.__key() == other.__key()
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.__key())
 

monasca_analytics/banana/typeck/type_util.py

@@ -79,6 +79,9 @@ class Any(IsType):
         # Any type is equal to nothing not even itself.
         return False
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __getitem__(self, _):
         return Any()
 
@@ -103,6 +106,9 @@ class String(IsType):
     def __eq__(self, other):
         return isinstance(other, String)
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(str(self))
 
@@ -124,6 +130,9 @@ class Number(String):
     def __eq__(self, other):
         return isinstance(other, Number)
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(str(self))
 
@@ -146,6 +155,9 @@ class Enum(String):
     def __eq__(self, other):
         return isinstance(other, Enum) and self.variants == other.variants
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.variants)
 
@@ -291,6 +303,9 @@ class Object(String):
     def __eq__(self, other):
         return self.props == other
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.props)
 
@@ -418,6 +433,9 @@ class Component(IsType):
     def __eq__(self, other):
         return isinstance(other, Component)
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(str(self))
 
@@ -442,6 +460,9 @@ class Source(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)
 
@@ -457,6 +478,9 @@ class Ingestor(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)
 
@@ -472,6 +496,9 @@ class Sink(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)
 
@@ -487,6 +514,9 @@ class Voter(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)
 
@@ -502,6 +532,9 @@ class Ldp(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)
 
@@ -517,6 +550,9 @@ class Sml(Component):
     def __eq__(self, other):
         return self.class_name == other.class_name
 
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
     def __hash__(self):
         return hash(self.class_name)