diff options
Diffstat (limited to 'pyparsing/testing.py')
| -rw-r--r-- | pyparsing/testing.py | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/pyparsing/testing.py b/pyparsing/testing.py new file mode 100644 index 0000000..b079c6d --- /dev/null +++ b/pyparsing/testing.py @@ -0,0 +1,190 @@ +# testing.py + +from contextlib import contextmanager +import unittest + +from pyparsing.core import ( + ParserElement, + ParseException, + Keyword, + __diag__, + __compat__, +) + + +class pyparsing_test: + """ + namespace class for classes useful in writing unit tests + """ + + class reset_pyparsing_context: + """ + Context manager to be used when writing unit tests that modify pyparsing config values: + - packrat parsing + - default whitespace characters. + - default keyword characters + - literal string auto-conversion class + - __diag__ settings + + Example: + with reset_pyparsing_context(): + # test that literals used to construct a grammar are automatically suppressed + ParserElement.inlineLiteralsUsing(Suppress) + + term = Word(alphas) | Word(nums) + group = Group('(' + term[...] + ')') + + # assert that the '()' characters are not included in the parsed tokens + self.assertParseAndCheckLisst(group, "(abc 123 def)", ['abc', '123', 'def']) + + # after exiting context manager, literals are converted to Literal expressions again + """ + + def __init__(self): + self._save_context = {} + + def save(self): + self._save_context["default_whitespace"] = ParserElement.DEFAULT_WHITE_CHARS + self._save_context["default_keyword_chars"] = Keyword.DEFAULT_KEYWORD_CHARS + self._save_context[ + "literal_string_class" + ] = ParserElement._literalStringClass + self._save_context["packrat_enabled"] = ParserElement._packratEnabled + self._save_context["packrat_parse"] = ParserElement._parse + self._save_context["__diag__"] = { + name: getattr(__diag__, name) for name in __diag__._all_names + } + self._save_context["__compat__"] = { + "collect_all_And_tokens": __compat__.collect_all_And_tokens + } + return self + + def restore(self): + # reset pyparsing global state + if ( + ParserElement.DEFAULT_WHITE_CHARS + != self._save_context["default_whitespace"] + ): + ParserElement.setDefaultWhitespaceChars( + self._save_context["default_whitespace"] + ) + Keyword.DEFAULT_KEYWORD_CHARS = self._save_context["default_keyword_chars"] + ParserElement.inlineLiteralsUsing( + self._save_context["literal_string_class"] + ) + for name, value in self._save_context["__diag__"].items(): + (__diag__.enable if value else __diag__.disable)(name) + ParserElement._packratEnabled = self._save_context["packrat_enabled"] + ParserElement._parse = self._save_context["packrat_parse"] + __compat__.collect_all_And_tokens = self._save_context["__compat__"] + + def __enter__(self): + return self.save() + + def __exit__(self, *args): + return self.restore() + + class TestParseResultsAsserts(unittest.TestCase): + def assertParseResultsEquals( + self, result, expected_list=None, expected_dict=None, msg=None + ): + """ + Unit test assertion to compare a ParseResults object with an optional expected_list, + and compare any defined results names with an optional expected_dict. + """ + if expected_list is not None: + self.assertEqual(expected_list, result.asList(), msg=msg) + if expected_dict is not None: + self.assertEqual(expected_dict, result.asDict(), msg=msg) + + def assertParseAndCheckList( + self, expr, test_string, expected_list, msg=None, verbose=True + ): + """ + Convenience wrapper assert to test a parser element and input string, and assert that + the resulting ParseResults.asList() is equal to the expected_list. + """ + result = expr.parseString(test_string, parseAll=True) + if verbose: + print(result.dump()) + self.assertParseResultsEquals(result, expected_list=expected_list, msg=msg) + + def assertParseAndCheckDict( + self, expr, test_string, expected_dict, msg=None, verbose=True + ): + """ + Convenience wrapper assert to test a parser element and input string, and assert that + the resulting ParseResults.asDict() is equal to the expected_dict. + """ + result = expr.parseString(test_string, parseAll=True) + if verbose: + print(result.dump()) + self.assertParseResultsEquals(result, expected_dict=expected_dict, msg=msg) + + def assertRunTestResults( + self, run_tests_report, expected_parse_results=None, msg=None + ): + """ + Unit test assertion to evaluate output of ParserElement.runTests(). If a list of + list-dict tuples is given as the expected_parse_results argument, then these are zipped + with the report tuples returned by runTests and evaluated using assertParseResultsEquals. + Finally, asserts that the overall runTests() success value is True. + + :param run_tests_report: tuple(bool, [tuple(str, ParseResults or Exception)]) returned from runTests + :param expected_parse_results (optional): [tuple(str, list, dict, Exception)] + """ + run_test_success, run_test_results = run_tests_report + + if expected_parse_results is not None: + merged = [ + (*rpt, expected) + for rpt, expected in zip(run_test_results, expected_parse_results) + ] + for test_string, result, expected in merged: + # expected should be a tuple containing a list and/or a dict or an exception, + # and optional failure message string + # an empty tuple will skip any result validation + fail_msg = next( + (exp for exp in expected if isinstance(exp, str)), None + ) + expected_exception = next( + ( + exp + for exp in expected + if isinstance(exp, type) and issubclass(exp, Exception) + ), + None, + ) + if expected_exception is not None: + with self.assertRaises( + expected_exception=expected_exception, msg=fail_msg or msg + ): + if isinstance(result, Exception): + raise result + else: + expected_list = next( + (exp for exp in expected if isinstance(exp, list)), None + ) + expected_dict = next( + (exp for exp in expected if isinstance(exp, dict)), None + ) + if (expected_list, expected_dict) != (None, None): + self.assertParseResultsEquals( + result, + expected_list=expected_list, + expected_dict=expected_dict, + msg=fail_msg or msg, + ) + else: + # warning here maybe? + print("no validation for {!r}".format(test_string)) + + # do this last, in case some specific test results can be reported instead + self.assertTrue( + run_test_success, msg=msg if msg is not None else "failed runTests" + ) + + @contextmanager + def assertRaisesParseException(self, exc_type=ParseException, msg=None): + with self.assertRaises(exc_type, msg=msg): + yield |