Fix parsing of memory accesses in tests

Apparently the current parser would fail on any memory accesses, both
loads and stores. In case of the former it's enough to try parsing the
memory accesses before variables. For stores, we can use backtracking
so that we don't consume the initial "m" of memory assignemnt thinking
that it's a variable identifier.

testing/Main.hs

@@ -30,6 +30,7 @@ goldensTests = Framework.testGroup "Goldens tests"
         , "test2"
         , "test3"
         , "test4"
+        , "test5"
         , "if-test"
         , "if-test2"
         , "if-test3"

testing/Parse.hs

@@ -47,6 +47,9 @@ reservedOp = P.reservedOp lexer
 whitespace :: CharParser () ()
 whitespace = P.whiteSpace lexer
 
+brackets :: CharParser () a -> CharParser () a
+brackets = P.brackets lexer
+
 -- Expressions:
 expr :: Parser Expr
 expr = buildExpressionParser table factor
@@ -60,8 +63,8 @@ expr = buildExpressionParser table factor
     op o f assoc = Infix (do {reservedOp o; return f} <?> "operator") assoc
     factor =   parens expr
            <|> lit
-           <|> fetchVar
            <|> load
+           <|> fetchVar
            <?> "simple Expression"
 
 bool :: Parser Bool
@@ -75,12 +78,7 @@ lit =  (natural >>= (return . Lit . Int))
    <?> "lit"
 
 loc :: Char -> Parser x -> Parser x
-loc s addr = try (lexeme (do { char' s
-                             ; char' '['
-                             ; a <- addr
-                             ; char' ']'
-                             ; return a
-                             }))
+loc s addr = try (lexeme (char' s >> brackets addr))
           <?> "loc"
 
 var :: Parser String
@@ -104,7 +102,7 @@ labl = lexeme (do { id <- identifier
   <?> "label"
 
 mid :: Parser Insn
-mid =   asst
+mid =   try asst
     <|> store
     <?> "assignment or store"
 

testing/tests/test5

+-- Tests parsing of memory stores and loads.
+procName(mm, aa) {
+L0:
+  m[aa] = m[mm] + m[aa]
+  ret(m[aa])
+}

testing/tests/test5.expected

+-- Tests parsing of memory stores and loads.
+procName(mm, aa) {
+L0:
+  m[aa] = m[mm] + m[aa]
+  ret(m[aa])
+}