From b905905c483fb976cc1166b39088c0b02b03d6a4 Mon Sep 17 00:00:00 2001
From: Jacques Wagener <jacques@dilectum.co.za>
Date: Wed, 15 Nov 2017 16:03:05 +0200
Subject: [PATCH] Add checks preventing assigning values on defining types.

---
 tests/parser/exceptions/test_structure_exception.py | 10 ++++++++++
 viper/parser/parser.py                              |  4 +++-
 viper/parser/stmt.py                                |  2 ++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/tests/parser/exceptions/test_structure_exception.py b/tests/parser/exceptions/test_structure_exception.py
index 5591d98dc2..764aea7517 100644
--- a/tests/parser/exceptions/test_structure_exception.py
+++ b/tests/parser/exceptions/test_structure_exception.py
@@ -131,6 +131,16 @@ def foo():
     """
 def foo():
     x = y = 3
+    """,
+    """
+def foo() -> num:
+    q:num = 111
+    return q
+    """,
+    """
+q:num = 111
+def foo() -> num:
+    return self.q
     """
 ]
 
diff --git a/viper/parser/parser.py b/viper/parser/parser.py
index 9e8394c5f5..ffcbcde519 100644
--- a/viper/parser/parser.py
+++ b/viper/parser/parser.py
@@ -171,7 +171,9 @@ def add_contract(code):
 
 
 def add_globals_and_events(_defs, _events, _getters, _globals, item):
-    if isinstance(item.annotation, ast.Call) and item.annotation.func.id == "__log__":
+    if item.value is not None:
+        raise StructureException('May not assign value whilst defining type', item)
+    elif isinstance(item.annotation, ast.Call) and item.annotation.func.id == "__log__":
         if _globals or len(_defs):
             raise StructureException("Events must all come before global declarations and function definitions", item)
         _events.append(item)
diff --git a/viper/parser/stmt.py b/viper/parser/stmt.py
index 635bcd54a8..a4715f4570 100644
--- a/viper/parser/stmt.py
+++ b/viper/parser/stmt.py
@@ -69,6 +69,8 @@ def parse_pass(self):
         return LLLnode.from_list('pass', typ=None, pos=getpos(self.stmt))
 
     def ann_assign(self):
+        if self.stmt.value is not None:
+            raise StructureException('May not assign value whilst defining type', self.stmt)
         typ = parse_type(self.stmt.annotation, location='memory')
         varname = self.stmt.target.id
         pos = self.context.new_variable(varname, typ)