bug fix: transform.has_parent now recognizes the oldest parent, too

DHParser/testing.py

@@ -339,6 +339,7 @@ def grammar_unit(test_unit, parser_factory, transformer_factory, report=True, ve
             try:
                 cst = parser(test_code, parser_name)
             except UnknownParserError as upe:
+                cst = RootNode()
                 cst = cst.new_error(Node(ZOMBIE_PARSER, "").init_pos(0), str(upe))
             clean_test_name = str(test_name).replace('*', '')
             # log_ST(cst, "match_%s_%s.cst" % (parser_name, clean_test_name))

DHParser/transform.py

@@ -472,7 +472,7 @@ def has_parent(context: List[Node], tag_name_set: AbstractSet[str]) -> bool:
     Checks whether a node with one of the given tag names appears somewhere
      in the context before the last node in the context.
      """
-    for i in range(2, len(context)):
+    for i in range(2, len(context) + 1):
         if context[-i].tag_name in tag_name_set:
             return True
     return False

test/test_testing.py

@@ -222,6 +222,7 @@ class TestGrammarTest:
         #     print(e)
         assert len(errata) == 3, str(errata)
 
+
     # def test_get_report(self):
     #     parser_fac = grammar_provider(ARITHMETIC_EBNF)
     #     trans_fac = lambda : ARITHMETIC_EBNFTransform

test/test_transform.py

@@ -28,7 +28,7 @@ from DHParser.syntaxtree import Node, parse_sxpr, flatten_sxpr, parse_xml, ZOMBI
     MockParser, TOKEN_PTYPE
 from DHParser.transform import traverse, reduce_single_child, remove_whitespace, \
     traverse_locally, collapse, collapse_if, lstrip, rstrip, remove_content, remove_tokens, \
-    transformation_factory
+    transformation_factory, has_parent
 from DHParser.toolkit import typing
 from typing import AbstractSet, List, Sequence, Tuple
 
@@ -157,6 +157,14 @@ class TestTransformationFactory:
 class TestConditionalTransformations:
     """Tests conditional transformations."""
 
+    def test_has_parent(self):
+        context = [Node(MockParser('A'), 'alpha'),
+                   Node(MockParser('B'), 'beta'),
+                   Node(MockParser('C'), 'gamma')]
+        assert has_parent(context, {'A'})
+        assert has_parent(context, {'B'})
+        assert not has_parent(context, {'C'})
+
     def test_traverse_locally(self):
         cst = parse_sxpr("""
             (Lemma