test_ebnf.py 11.7 KB
Newer Older
1
2
#!/usr/bin/python3

3
"""test_ebnf.py - tests of the ebnf module of DHParser 
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
                             

Author: Eckhart Arnold <arnold@badw.de>

Copyright 2017 Bavarian Academy of Sciences and Humanities

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
"""

Eckhart Arnold's avatar
Eckhart Arnold committed
23
import sys
24
from functools import partial
Eckhart Arnold's avatar
Eckhart Arnold committed
25
from multiprocessing import Pool
Eckhart Arnold's avatar
Eckhart Arnold committed
26

Eckhart Arnold's avatar
Eckhart Arnold committed
27
28
sys.path.extend(['../', './'])

29
from DHParser.toolkit import is_logging, compile_python_object
30
from DHParser.parsers import compile_source, Retrieve, WHITESPACE_PTYPE, nil_scanner
31
from DHParser.ebnf import get_ebnf_grammar, get_ebnf_transformer, EBNFTransformer, get_ebnf_compiler
32
from DHParser.dsl import CompilationError, compileDSL, DHPARSER_IMPORTS, parser_factory
33
34


35
36
37
38
39
40
41
42
43
44
45
class TestDirectives:
    mini_language = """
        expression =  term  { ("+" | "-") term }
        term       =  factor  { ("*" | "/") factor }
        factor     =  constant | "("  expression  ")"
        constant   =  digit { digit } [ //~ ]
        digit      = /0/ | /1/ | /2/ | /3/ | /4/ | /5/ | /6/ | /7/ | /8/ | /9/ 
        """

    def test_whitespace_linefeed(self):
        lang = "@ whitespace = linefeed\n" + self.mini_language
46
        MinilangParser = parser_factory(lang)
47
48
        parser = MinilangParser()
        assert parser
Eckhart Arnold's avatar
Eckhart Arnold committed
49
        syntax_tree = parser("3 + 4 * 12")
50
        # parser.log_parsing_history("WSP")
51
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
52
        syntax_tree = parser("3 + 4 \n * 12")
53
54
        # parser.log_parsing_history("WSPLF")
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
55
        syntax_tree = parser("3 + 4 \n \n * 12")
56
        assert syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
57
        syntax_tree = parser("3 + 4 \n\n * 12")
58
59
60
61
        assert syntax_tree.collect_errors()

    def test_whitespace_vertical(self):
        lang = "@ whitespace = vertical\n" + self.mini_language
62
        parser = parser_factory(lang)()
63
        assert parser
Eckhart Arnold's avatar
Eckhart Arnold committed
64
        syntax_tree = parser("3 + 4 * 12")
65
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
66
        syntax_tree = parser("3 + 4 \n * 12")
67
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
68
        syntax_tree = parser("3 + 4 \n \n * 12")
69
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
70
        syntax_tree = parser("3 + 4 \n\n * 12")
71
72
        assert not syntax_tree.collect_errors()

73
74
    def test_whitespace_horizontal(self):
        lang = "@ whitespace = horizontal\n" + self.mini_language
75
        parser = parser_factory(lang)()
76
        assert parser
Eckhart Arnold's avatar
Eckhart Arnold committed
77
        syntax_tree = parser("3 + 4 * 12")
78
        assert not syntax_tree.collect_errors()
Eckhart Arnold's avatar
Eckhart Arnold committed
79
        syntax_tree = parser("3 + 4 \n * 12")
80
81
        assert syntax_tree.collect_errors()

82

83
class TestEBNFParser:
Eckhart Arnold's avatar
Eckhart Arnold committed
84
    cases = {
85
86
87
88
89
90
91
92
93
94
95
96
97
98
        "list_": {
            "match": {
                1: "hund",
                2: "hund, katze,maus",
                3: "hund , katze"
            },
            "fail": {
                1: "123",
                2: '"literal"',
                3: "/regexp/"
            }
        }
    }

di68kap's avatar
di68kap committed
99

100
    def setup(self):
Eckhart Arnold's avatar
Eckhart Arnold committed
101
        self.EBNF = get_ebnf_grammar()
102

103
104
105
106
107
    def test_RE(self):
        gr = get_ebnf_grammar()
        m = gr.regexp.main.regexp.match(r'/\\/ xxx /')
        assert m.group().find('x') < 0, m.group()

108
109
    def test_literal(self):
        snippet = '"literal" '
Eckhart Arnold's avatar
Eckhart Arnold committed
110
        result = self.EBNF(snippet, 'literal')
111
112
        assert not result.error_flag
        assert str(result) == snippet
113
        assert result.find(lambda node: node.parser.ptype == WHITESPACE_PTYPE)
114

Eckhart Arnold's avatar
Eckhart Arnold committed
115
        result = self.EBNF(' "literal"', 'literal')
116
117
118
        assert result.error_flag  # literals catch following, but not leading whitespace


119
120
class TestSemanticValidation:
    def check(self, minilang, bool_filter=lambda x: x):
Eckhart Arnold's avatar
Eckhart Arnold committed
121
        grammar = get_ebnf_grammar()
Eckhart Arnold's avatar
Eckhart Arnold committed
122
        st = grammar(minilang)
123
        assert not st.collect_errors()
124
        EBNFTransformer(st)
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
        assert bool_filter(st.collect_errors())

    def test_illegal_nesting(self):
        self.check('impossible = { [ "an optional requirement" ] }')

    def test_illegal_nesting_option_required(self):
        self.check('impossible = [ §"an optional requirement" ]')

    def test_illegal_nesting_oneormore_option(self):
        self.check('impossible = { [ "no use"] }+')

    def test_legal_nesting(self):
        self.check('possible = { [ "+" ] "1" }', lambda x: not x)


class TestCompilerErrors:
    def test_error_propagation(self):
142
        ebnf = "@ literalws = wrongvalue  # testing error propagation\n"
Eckhart Arnold's avatar
Eckhart Arnold committed
143
144
        result, messages, st = compile_source(ebnf, None, get_ebnf_grammar(),
            get_ebnf_transformer(), get_ebnf_compiler('ErrorPropagationTest'))
145
146
        assert messages

147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
    def test_undefined_symbols(self):
        """Use of undefined symbols should be reported.
        """
        ebnf = """syntax = { intermediary }
                  intermediary = "This symbol is " [ badly_spelled ] "!"
                  bedly_spilled = "wrong" """
        result, messages, st = compile_source(ebnf, None, get_ebnf_grammar(),
            get_ebnf_transformer(), get_ebnf_compiler('UndefinedSymbols'))
        assert messages

    def test_no_error(self):
        """But reserved symbols should not be repoted as undefined.
        """
        ebnf = """nothing =  WSP__ | COMMENT__\n"""
        result, messages, st = compile_source(ebnf, None, get_ebnf_grammar(),
            get_ebnf_transformer(), get_ebnf_compiler('UndefinedSymbols'))
        assert not bool(messages), messages

165

166
class TestSelfHosting:
Eckhart Arnold's avatar
Eckhart Arnold committed
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
    grammar = r"""
        # EBNF-Grammar in EBNF

        @ comment    =  /#.*(?:\n|$)/                    # comments start with '#' and eat all chars up to and including '\n'
        @ whitespace =  /\s*/                            # whitespace includes linefeed
        @ literalws  =  right                            # trailing whitespace of literals will be ignored tacitly

        syntax     =  [~//] { definition | directive } §EOF
        definition =  symbol §"=" expression
        directive  =  "@" §symbol §"=" ( regexp | literal | list_ )

        expression =  term { "|" term }
        term       =  { factor }+
        factor     =  [flowmarker] [retrieveop] symbol !"="   # negative lookahead to be sure it's not a definition
                    | [flowmarker] literal
                    | [flowmarker] regexp
                    | [flowmarker] group
                    | [flowmarker] regexchain
                    | [flowmarker] oneormore
                    | repetition
                    | option

        flowmarker =  "!"  | "&"  | "§" |                # '!' negative lookahead, '&' positive lookahead, '§' required
                      "-!" | "-&"                        # '-' negative lookbehind, '-&' positive lookbehind
        retrieveop =  "::" | ":"                         # '::' pop, ':' retrieve

        group      =  "(" expression §")"
        regexchain =  ">" expression §"<"                # compiles "expression" into a singular regular expression
        oneormore  =  "{" expression "}+"
        repetition =  "{" expression §"}"
        option     =  "[" expression §"]"

        symbol     =  /(?!\d)\w+/~                       # e.g. expression, factor, parameter_list
        literal    =  /"(?:[^"]|\\")*?"/~                # e.g. "(", '+', 'while'
                    | /'(?:[^']|\\')*?'/~                # whitespace following literals will be ignored tacitly.
        regexp     =  /~?\/(?:[^\/]|(?<=\\)\/)*\/~?/~    # e.g. /\w+/, ~/#.*(?:\n|$)/~
                                                         # '~' is a whitespace-marker, if present leading or trailing
                                                         # whitespace of a regular expression will be ignored tacitly.
        list_      =  /\w+/~ { "," /\w+/~ }              # comma separated list of symbols, e.g. BEGIN_LIST, END_LIST,
                                                         # BEGIN_QUOTE, END_QUOTE ; see CommonMark/markdown.py for an exmaple
        EOF =  !/./        
        """

210
211
    def test_self(self):
        compiler_name = "EBNF"
Eckhart Arnold's avatar
Eckhart Arnold committed
212
213
214
215
        compiler = get_ebnf_compiler(compiler_name, self.grammar)
        parser = get_ebnf_grammar()
        result, errors, syntax_tree = compile_source(self.grammar, None, parser,
                                            get_ebnf_transformer(), compiler)
216
217
218
        assert not errors, str(errors)
        # compile the grammar again using the result of the previous
        # compilation as parser
Eckhart Arnold's avatar
Eckhart Arnold committed
219
        compileDSL(self.grammar, nil_scanner, result, get_ebnf_transformer(), compiler)
220

Eckhart Arnold's avatar
Eckhart Arnold committed
221
222
223
224
225
226
227
228
229
230
231
    def multiprocessing_task(self):
        compiler_name = "EBNF"
        compiler = get_ebnf_compiler(compiler_name, self.grammar)
        parser = get_ebnf_grammar()
        result, errors, syntax_tree = compile_source(self.grammar, None, parser,
                                            get_ebnf_transformer(), compiler)
        return errors

    def test_multiprocessing(self):
        with Pool(processes=2) as pool:
            res = [pool.apply_async(self.multiprocessing_task, ()) for i in range(4)]
232
            errors = [r.get(timeout=10) for r in res]
Eckhart Arnold's avatar
Eckhart Arnold committed
233
234
        for i, e in enumerate(errors):
            assert not e, ("%i: " % i) + str(e)
235
236


237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
class TestBoundaryCases:
    def setup(self):
        self.gr = get_ebnf_grammar()
        self.tr = get_ebnf_transformer()
        self.cp = get_ebnf_compiler()

    def test_empty_grammar(self):
        t = self.gr("")
        self.tr(t)
        r = self.cp(t)
        assert r

    def test_single_statement_grammar(self):
        t = self.gr("i = /i/")
        self.tr(t)
        r = self.cp(t)
        assert r

    def test_two_statement_grammar(self):
        t = self.gr("i = k {k}\nk = /k/")
        self.tr(t)
        r = self.cp(t)
        assert r

261
262
263
264
265
    def test_unconnected_symbols(self):
        ebnf = """root = /.*/
                  unconnected = /.*/
        """
        try:
266
            grammar = parser_factory(ebnf)()
267
268
            assert False, "EBNF compiler should complain about unconnected rules."
        except CompilationError as err:
269
270
271
272
273
274
275
            grammar_src = err.result
            grammar = compile_python_object(DHPARSER_IMPORTS + grammar_src,
                                            'get_(?:\w+_)?grammar$')()
        assert grammar['root'], "Grammar objects should be subscriptable by parser names!"
        try:
            unconnected = grammar['unconnected']
        except KeyError:
Eckhart Arnold's avatar
Eckhart Arnold committed
276
            assert False, "Grammar objects should be able to cope with unconnected parsers!"
277
278
279
280
281
282
        try:
            nonexistant = grammar['nonexistant']
            assert False, "Grammar object shoul raise a KeyError if subscripted by " \
                          "a non-existant parser name!"
        except KeyError:
            pass
283
284
285
286
287
288
        ebnf_testing = "@testing = True\n" + ebnf
        try:
            grammar = parser_factory(ebnf_testing)()
        except CompilationError:
            assert False, "EBNF compiler should not complain about unconnected " \
                          "rules when directive @testing is set."
289
290
291
292
293
294
295
296
297
298


class TestSynonymDetection:
    def test_synonym_detection(self):
        ebnf = """a = b
                  b = /b/
        """
        grammar = parser_factory(ebnf)()
        assert grammar['a'].name == 'a', grammar['a'].name
        assert grammar['b'].name == 'b', grammar['b'].name
299
        assert grammar('b').as_sxpr().count('b') == 2
300

301

302
if __name__ == "__main__":
303
304
    from DHParser.testing import runner
    runner("", globals())