Add test for string concatenation

interface/HUTN/test/constructor_compilation_action_language/code/string_concat.al

@@ -0,0 +1,7 @@
+Element string_join = ?primitives/string_join
+Element integer_addition = ?primitives/integer_addition
+
+Void function main():
+	Integer a
+	a = 1 + 2 + 3
+	return!

interface/HUTN/test/constructor_compilation_action_language/expected/string_concat

@@ -0,0 +1 @@
+[42, "global", "string_join", "deref", "primitives/string_join", true, "global", "integer_addition", "deref", "primitives/integer_addition", true, "funcdef", "main", 0, "declare", "0", "none", true, "assign", "resolve", "0", "call", "access", "resolve", "integer_addition", 2, "call", "access", "resolve", "integer_addition", 2, "const", 1, "const", 2, false, "const", 3, false, true, "return", false, false]

interface/HUTN/test/constructor_compilation_action_language/test_compile.py

@@ -9,10 +9,10 @@ def compile_file(obj, filename):
     try:
         expected = json.loads(open(util.get_expected_path(filename)).read())
     except:
-        #f = open(util.get_expected_path(filename), 'w')
-        #f.write(json.dumps(result))
-        #f.close()
-        pass
+        f = open(util.get_expected_path(filename), 'w')
+        f.write(json.dumps(result))
+        f.close()
+        expected = None
     assert result == expected
 
 class TestCompile(unittest.TestCase):
@@ -69,3 +69,6 @@ class TestCompile(unittest.TestCase):
 
     def test_strange_return(self):
         compile_file(self, "strange_return.al")
+
+    def test_string_concat(self):
+        compile_file(self, "string_concat.al")