debt: Align Python syntax error messages

python/cucumber_tag_expressions/parser.py

@@ -221,8 +221,10 @@ def parse(cls, text):
 
         def ensure_expected_token_type(token_type, index):
             if expected_token_type != token_type:
-                message = "Syntax error. Expected %s after %s" % \
-                          (expected_token_type.name.lower(), last_part)
+                message = (
+                    'Tag expression "%s" could not be parsed because of syntax '
+                    'error: Expected %s.' % (text, expected_token_type.name.lower())
+                )
                 message = cls._make_error_description(message, parts, index)
                 raise TagExpressionError(message)
 

python/tests/unit/test_parser.py

@@ -200,34 +200,34 @@ def test_parse__fails_with_unbalanced_parens(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
-        ("a not ( and )", "Syntax error. Expected operator after a"),
+        ("a not ( and )", "syntax error: Expected operator"),
     ])
     def test_parse__fails_with_missing_operation_args(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
-        ("or or",  "Syntax error. Expected operand after BEGIN"),
+        ("or or",  "syntax error: Expected operand"),
     ])
     def test_parse__fails_with_only_operations(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
-        ("a b", "Syntax error. Expected operator after a"),
+        ("a b", "syntax error: Expected operator"),
     ])
     def test_parse__fails_for_args_without_operation(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
-        ("(())",    "Syntax error. Expected operand after ("),
-        ("(() ())", "Syntax error. Expected operand after ("),
+        ("(())",    "syntax error: Expected operand"),
+        ("(() ())", "syntax error: Expected operand"),
     ])
     def test_parse__fails_for_empty_parens_groups(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, expected", [
-        ("a b or",        "Syntax error. Expected operator after a"),
-        ("a and (b not)", "Syntax error. Expected operator after b"),
-        ("a and (b c) or", "Syntax error. Expected operator after b"),
+        ("a b or",        "syntax error: Expected operator"),
+        ("a and (b not)", "syntax error: Expected operator"),
+        ("a and (b c) or", "syntax error: Expected operator"),
     ])
     def test_parse__fails_with_rpn_notation(self, text, expected):
         # -- NOTE: RPN parsebility due to Shunting-yard algorithm (stack-based).
@@ -252,24 +252,24 @@ def test_parse__fails_with_rpn_notation(self, text, expected):
     # -- BAD CASES: Too few operands
     @pytest.mark.parametrize("text, error_message", [
         ("a and ",  "and: Too few operands"),
-        ("  and b", "Syntax error. Expected operand after BEGIN"),
+        ("  and b", "syntax error: Expected operand"),
     ])
     def test_parse__fails_and_operation_with_too_few_args(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
         ("a or ",  "or: Too few operands"),
-        ("  or b", "Syntax error. Expected operand after BEGIN"),
+        ("  or b", "syntax error: Expected operand"),
         ("a and b or ", "or: Too few operands"),
     ])
     def test_parse__fails_or_operation_with_too_few_args(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)
 
     @pytest.mark.parametrize("text, error_message", [
         ("not ",   "not: Too few operands"),
-        ("not ()",       "Syntax error. Expected operand after ("),
-        ("not () and b", "Syntax error. Expected operand after ("),
-        ("not () or b",  "Syntax error. Expected operand after ("),
+        ("not ()",       "syntax error: Expected operand"),
+        ("not () and b", "syntax error: Expected operand"),
+        ("not () or b",  "syntax error: Expected operand"),
     ])
     def test_parse__fails_not_operation_with_too_few_args(self, text, error_message):
         self.assert_parse_with_error_contains_message(text, error_message)