summaryrefslogtreecommitdiff
path: root/pyparsing/testing.py
blob: 43f23abdcc00e335051b852189541eb52eb9c188 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
# testing.py

from contextlib import contextmanager

from .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
         - bounded recursion 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.assertParseAndCheckList(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["verbose_stacktrace"] = ParserElement.verbose_stacktrace

            self._save_context["packrat_enabled"] = ParserElement._packratEnabled
            if ParserElement._packratEnabled:
                self._save_context[
                    "packrat_cache_size"
                ] = ParserElement.packrat_cache.size
            else:
                self._save_context["packrat_cache_size"] = None
            self._save_context["packrat_parse"] = ParserElement._parse
            self._save_context["recursion_enabled"] = ParserElement._left_recursion_enabled

            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"]
                )

            ParserElement.verbose_stacktrace = self._save_context["verbose_stacktrace"]

            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 = False
            if self._save_context["packrat_enabled"]:
                ParserElement.enablePackrat(self._save_context["packrat_cache_size"])
            else:
                ParserElement._parse = self._save_context["packrat_parse"]
            ParserElement._left_recursion_enabled = self._save_context["recursion_enabled"]

            __compat__.collect_all_And_tokens = self._save_context["__compat__"]

            return self

        def copy(self):
            ret = type(self)()
            ret._save_context.update(self._save_context)
            return ret

        def __enter__(self):
            return self.save()

        def __exit__(self, *args):
            self.restore()

    class TestParseResultsAsserts:
        """
        A mixin class to add parse results assertion methods to normal unittest.TestCase classes.
        """

        def assertParseResultsEquals(
            self, result, expected_list=None, expected_dict=None, msg=None
        ):
            """
            Unit test assertion to compare a :class:`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