Source

cpython_sandbox / Lib / test / test_importlib / test_abc.py

  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
227
228
229
230
231
232
233
234
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
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
import importlib
from importlib import abc
from importlib import machinery

import imp
import inspect
import io
import marshal
import os
import sys
import unittest
from unittest import mock

from . import util

##### Inheritance ##############################################################
class InheritanceTests:

    """Test that the specified class is a subclass/superclass of the expected
    classes."""

    subclasses = []
    superclasses = []

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        assert self.subclasses or self.superclasses, self.__class__
        self.__test = getattr(abc, self.__class__.__name__)

    def test_subclasses(self):
        # Test that the expected subclasses inherit.
        for subclass in self.subclasses:
            self.assertTrue(issubclass(subclass, self.__test),
                "{0} is not a subclass of {1}".format(subclass, self.__test))

    def test_superclasses(self):
        # Test that the class inherits from the expected superclasses.
        for superclass in self.superclasses:
            self.assertTrue(issubclass(self.__test, superclass),
               "{0} is not a superclass of {1}".format(superclass, self.__test))


class MetaPathFinder(InheritanceTests, unittest.TestCase):

    superclasses = [abc.Finder]
    subclasses = [machinery.BuiltinImporter, machinery.FrozenImporter,
                    machinery.PathFinder, machinery.WindowsRegistryFinder]


class PathEntryFinder(InheritanceTests, unittest.TestCase):

    superclasses = [abc.Finder]
    subclasses = [machinery.FileFinder]


class ResourceLoader(InheritanceTests, unittest.TestCase):

    superclasses = [abc.Loader]


class InspectLoader(InheritanceTests, unittest.TestCase):

    superclasses = [abc.Loader]
    subclasses = [machinery.BuiltinImporter,
                    machinery.FrozenImporter, machinery.ExtensionFileLoader]


class ExecutionLoader(InheritanceTests, unittest.TestCase):

    superclasses = [abc.InspectLoader]


class FileLoader(InheritanceTests, unittest.TestCase):

    superclasses = [abc.ResourceLoader, abc.ExecutionLoader]
    subclasses = [machinery.SourceFileLoader, machinery.SourcelessFileLoader]


class SourceLoader(InheritanceTests, unittest.TestCase):

    superclasses = [abc.ResourceLoader, abc.ExecutionLoader]
    subclasses = [machinery.SourceFileLoader]


##### Default return values ####################################################
class MetaPathFinderSubclass(abc.MetaPathFinder):

    def find_module(self, fullname, path):
        return super().find_module(fullname, path)


class MetaPathFinderDefaultsTests(unittest.TestCase):

    ins = MetaPathFinderSubclass()

    def test_find_module(self):
        # Default should return None.
        self.assertIsNone(self.ins.find_module('something', None))

    def test_invalidate_caches(self):
        # Calling the method is a no-op.
        self.ins.invalidate_caches()


class PathEntryFinderSubclass(abc.PathEntryFinder):

    def find_loader(self, fullname):
        return super().find_loader(fullname)


class PathEntryFinderDefaultsTests(unittest.TestCase):

    ins = PathEntryFinderSubclass()

    def test_find_loader(self):
        self.assertEqual((None, []), self.ins.find_loader('something'))

    def find_module(self):
        self.assertEqual(None, self.ins.find_module('something'))

    def test_invalidate_caches(self):
        # Should be a no-op.
        self.ins.invalidate_caches()


class LoaderSubclass(abc.Loader):

    def load_module(self, fullname):
        return super().load_module(fullname)


class LoaderDefaultsTests(unittest.TestCase):

    ins = LoaderSubclass()

    def test_load_module(self):
        with self.assertRaises(ImportError):
            self.ins.load_module('something')

    def test_module_repr(self):
        mod = imp.new_module('blah')
        with self.assertRaises(NotImplementedError):
            self.ins.module_repr(mod)
        original_repr = repr(mod)
        mod.__loader__ = self.ins
        # Should still return a proper repr.
        self.assertTrue(repr(mod))


class ResourceLoaderSubclass(LoaderSubclass, abc.ResourceLoader):

    def get_data(self, path):
        return super().get_data(path)


class ResourceLoaderDefaultsTests(unittest.TestCase):

    ins = ResourceLoaderSubclass()

    def test_get_data(self):
        with self.assertRaises(IOError):
            self.ins.get_data('/some/path')


class InspectLoaderSubclass(LoaderSubclass, abc.InspectLoader):

    def is_package(self, fullname):
        return super().is_package(fullname)

    def get_source(self, fullname):
        return super().get_source(fullname)


class InspectLoaderDefaultsTests(unittest.TestCase):

    ins = InspectLoaderSubclass()

    def test_is_package(self):
        with self.assertRaises(ImportError):
            self.ins.is_package('blah')

    def test_get_source(self):
        with self.assertRaises(ImportError):
            self.ins.get_source('blah')


class ExecutionLoaderSubclass(InspectLoaderSubclass, abc.ExecutionLoader):

    def get_filename(self, fullname):
        return super().get_filename(fullname)


class ExecutionLoaderDefaultsTests(unittest.TestCase):

    ins = ExecutionLoaderSubclass()

    def test_get_filename(self):
        with self.assertRaises(ImportError):
            self.ins.get_filename('blah')


##### InspectLoader concrete methods ###########################################
class InspectLoaderSourceToCodeTests(unittest.TestCase):

    def source_to_module(self, data, path=None):
        """Help with source_to_code() tests."""
        module = imp.new_module('blah')
        loader = InspectLoaderSubclass()
        if path is None:
            code = loader.source_to_code(data)
        else:
            code = loader.source_to_code(data, path)
        exec(code, module.__dict__)
        return module

    def test_source_to_code_source(self):
        # Since compile() can handle strings, so should source_to_code().
        source = 'attr = 42'
        module = self.source_to_module(source)
        self.assertTrue(hasattr(module, 'attr'))
        self.assertEqual(module.attr, 42)

    def test_source_to_code_bytes(self):
        # Since compile() can handle bytes, so should source_to_code().
        source = b'attr = 42'
        module = self.source_to_module(source)
        self.assertTrue(hasattr(module, 'attr'))
        self.assertEqual(module.attr, 42)

    def test_source_to_code_path(self):
        # Specifying a path should set it for the code object.
        path = 'path/to/somewhere'
        loader = InspectLoaderSubclass()
        code = loader.source_to_code('', path)
        self.assertEqual(code.co_filename, path)

    def test_source_to_code_no_path(self):
        # Not setting a path should still work and be set to <string> since that
        # is a pre-existing practice as a default to compile().
        loader = InspectLoaderSubclass()
        code = loader.source_to_code('')
        self.assertEqual(code.co_filename, '<string>')


class InspectLoaderGetCodeTests(unittest.TestCase):

    def test_get_code(self):
        # Test success.
        module = imp.new_module('blah')
        with mock.patch.object(InspectLoaderSubclass, 'get_source') as mocked:
            mocked.return_value = 'attr = 42'
            loader = InspectLoaderSubclass()
            code = loader.get_code('blah')
        exec(code, module.__dict__)
        self.assertEqual(module.attr, 42)

    def test_get_code_source_is_None(self):
        # If get_source() is None then this should be None.
        with mock.patch.object(InspectLoaderSubclass, 'get_source') as mocked:
            mocked.return_value = None
            loader = InspectLoaderSubclass()
            code = loader.get_code('blah')
        self.assertIsNone(code)

    def test_get_code_source_not_found(self):
        # If there is no source then there is no code object.
        loader = InspectLoaderSubclass()
        with self.assertRaises(ImportError):
            loader.get_code('blah')


##### ExecutionLoader concrete methods #########################################
class ExecutionLoaderGetCodeTests(unittest.TestCase):

    def mock_methods(self, *, get_source=False, get_filename=False):
        source_mock_context, filename_mock_context = None, None
        if get_source:
            source_mock_context = mock.patch.object(ExecutionLoaderSubclass,
                                                    'get_source')
        if get_filename:
            filename_mock_context = mock.patch.object(ExecutionLoaderSubclass,
                                                      'get_filename')
        return source_mock_context, filename_mock_context

    def test_get_code(self):
        path = 'blah.py'
        source_mock_context, filename_mock_context = self.mock_methods(
                get_source=True, get_filename=True)
        with source_mock_context as source_mock, filename_mock_context as name_mock:
            source_mock.return_value = 'attr = 42'
            name_mock.return_value = path
            loader = ExecutionLoaderSubclass()
            code = loader.get_code('blah')
        self.assertEqual(code.co_filename, path)
        module = imp.new_module('blah')
        exec(code, module.__dict__)
        self.assertEqual(module.attr, 42)

    def test_get_code_source_is_None(self):
        # If get_source() is None then this should be None.
        source_mock_context, _ = self.mock_methods(get_source=True)
        with source_mock_context as mocked:
            mocked.return_value = None
            loader = ExecutionLoaderSubclass()
            code = loader.get_code('blah')
        self.assertIsNone(code)

    def test_get_code_source_not_found(self):
        # If there is no source then there is no code object.
        loader = ExecutionLoaderSubclass()
        with self.assertRaises(ImportError):
            loader.get_code('blah')

    def test_get_code_no_path(self):
        # If get_filename() raises ImportError then simply skip setting the path
        # on the code object.
        source_mock_context, filename_mock_context = self.mock_methods(
                get_source=True, get_filename=True)
        with source_mock_context as source_mock, filename_mock_context as name_mock:
            source_mock.return_value = 'attr = 42'
            name_mock.side_effect = ImportError
            loader = ExecutionLoaderSubclass()
            code = loader.get_code('blah')
        self.assertEqual(code.co_filename, '<string>')
        module = imp.new_module('blah')
        exec(code, module.__dict__)
        self.assertEqual(module.attr, 42)



##### SourceLoader concrete methods ############################################
class SourceOnlyLoaderMock(abc.SourceLoader):

    # Globals that should be defined for all modules.
    source = (b"_ = '::'.join([__name__, __file__, __cached__, __package__, "
              b"repr(__loader__)])")

    def __init__(self, path):
        self.path = path

    def get_data(self, path):
        if path != self.path:
            raise IOError
        return self.source

    def get_filename(self, fullname):
        return self.path

    def module_repr(self, module):
        return '<module>'


class SourceLoaderMock(SourceOnlyLoaderMock):

    source_mtime = 1

    def __init__(self, path, magic=imp.get_magic()):
        super().__init__(path)
        self.bytecode_path = imp.cache_from_source(self.path)
        self.source_size = len(self.source)
        data = bytearray(magic)
        data.extend(importlib._w_long(self.source_mtime))
        data.extend(importlib._w_long(self.source_size))
        code_object = compile(self.source, self.path, 'exec',
                                dont_inherit=True)
        data.extend(marshal.dumps(code_object))
        self.bytecode = bytes(data)
        self.written = {}

    def get_data(self, path):
        if path == self.path:
            return super().get_data(path)
        elif path == self.bytecode_path:
            return self.bytecode
        else:
            raise OSError

    def path_stats(self, path):
        if path != self.path:
            raise IOError
        return {'mtime': self.source_mtime, 'size': self.source_size}

    def set_data(self, path, data):
        self.written[path] = bytes(data)
        return path == self.bytecode_path


class SourceLoaderTestHarness(unittest.TestCase):

    def setUp(self, *, is_package=True, **kwargs):
        self.package = 'pkg'
        if is_package:
            self.path = os.path.join(self.package, '__init__.py')
            self.name = self.package
        else:
            module_name = 'mod'
            self.path = os.path.join(self.package, '.'.join(['mod', 'py']))
            self.name = '.'.join([self.package, module_name])
        self.cached = imp.cache_from_source(self.path)
        self.loader = self.loader_mock(self.path, **kwargs)

    def verify_module(self, module):
        self.assertEqual(module.__name__, self.name)
        self.assertEqual(module.__file__, self.path)
        self.assertEqual(module.__cached__, self.cached)
        self.assertEqual(module.__package__, self.package)
        self.assertEqual(module.__loader__, self.loader)
        values = module._.split('::')
        self.assertEqual(values[0], self.name)
        self.assertEqual(values[1], self.path)
        self.assertEqual(values[2], self.cached)
        self.assertEqual(values[3], self.package)
        self.assertEqual(values[4], repr(self.loader))

    def verify_code(self, code_object):
        module = imp.new_module(self.name)
        module.__file__ = self.path
        module.__cached__ = self.cached
        module.__package__ = self.package
        module.__loader__ = self.loader
        module.__path__ = []
        exec(code_object, module.__dict__)
        self.verify_module(module)


class SourceOnlyLoaderTests(SourceLoaderTestHarness):

    """Test importlib.abc.SourceLoader for source-only loading.

    Reload testing is subsumed by the tests for
    importlib.util.module_for_loader.

    """

    loader_mock = SourceOnlyLoaderMock

    def test_get_source(self):
        # Verify the source code is returned as a string.
        # If an OSError is raised by get_data then raise ImportError.
        expected_source = self.loader.source.decode('utf-8')
        self.assertEqual(self.loader.get_source(self.name), expected_source)
        def raise_OSError(path):
            raise OSError
        self.loader.get_data = raise_OSError
        with self.assertRaises(ImportError) as cm:
            self.loader.get_source(self.name)
        self.assertEqual(cm.exception.name, self.name)

    def test_is_package(self):
        # Properly detect when loading a package.
        self.setUp(is_package=False)
        self.assertFalse(self.loader.is_package(self.name))
        self.setUp(is_package=True)
        self.assertTrue(self.loader.is_package(self.name))
        self.assertFalse(self.loader.is_package(self.name + '.__init__'))

    def test_get_code(self):
        # Verify the code object is created.
        code_object = self.loader.get_code(self.name)
        self.verify_code(code_object)

    def test_source_to_code(self):
        # Verify the compiled code object.
        code = self.loader.source_to_code(self.loader.source, self.path)
        self.verify_code(code)

    def test_load_module(self):
        # Loading a module should set __name__, __loader__, __package__,
        # __path__ (for packages), __file__, and __cached__.
        # The module should also be put into sys.modules.
        with util.uncache(self.name):
            module = self.loader.load_module(self.name)
            self.verify_module(module)
            self.assertEqual(module.__path__, [os.path.dirname(self.path)])
            self.assertIn(self.name, sys.modules)

    def test_package_settings(self):
        # __package__ needs to be set, while __path__ is set on if the module
        # is a package.
        # Testing the values for a package are covered by test_load_module.
        self.setUp(is_package=False)
        with util.uncache(self.name):
            module = self.loader.load_module(self.name)
            self.verify_module(module)
            self.assertTrue(not hasattr(module, '__path__'))

    def test_get_source_encoding(self):
        # Source is considered encoded in UTF-8 by default unless otherwise
        # specified by an encoding line.
        source = "_ = 'ü'"
        self.loader.source = source.encode('utf-8')
        returned_source = self.loader.get_source(self.name)
        self.assertEqual(returned_source, source)
        source = "# coding: latin-1\n_ = ü"
        self.loader.source = source.encode('latin-1')
        returned_source = self.loader.get_source(self.name)
        self.assertEqual(returned_source, source)


@unittest.skipIf(sys.dont_write_bytecode, "sys.dont_write_bytecode is true")
class SourceLoaderBytecodeTests(SourceLoaderTestHarness):

    """Test importlib.abc.SourceLoader's use of bytecode.

    Source-only testing handled by SourceOnlyLoaderTests.

    """

    loader_mock = SourceLoaderMock

    def verify_code(self, code_object, *, bytecode_written=False):
        super().verify_code(code_object)
        if bytecode_written:
            self.assertIn(self.cached, self.loader.written)
            data = bytearray(imp.get_magic())
            data.extend(importlib._w_long(self.loader.source_mtime))
            data.extend(importlib._w_long(self.loader.source_size))
            data.extend(marshal.dumps(code_object))
            self.assertEqual(self.loader.written[self.cached], bytes(data))

    def test_code_with_everything(self):
        # When everything should work.
        code_object = self.loader.get_code(self.name)
        self.verify_code(code_object)

    def test_no_bytecode(self):
        # If no bytecode exists then move on to the source.
        self.loader.bytecode_path = "<does not exist>"
        # Sanity check
        with self.assertRaises(OSError):
            bytecode_path = imp.cache_from_source(self.path)
            self.loader.get_data(bytecode_path)
        code_object = self.loader.get_code(self.name)
        self.verify_code(code_object, bytecode_written=True)

    def test_code_bad_timestamp(self):
        # Bytecode is only used when the timestamp matches the source EXACTLY.
        for source_mtime in (0, 2):
            assert source_mtime != self.loader.source_mtime
            original = self.loader.source_mtime
            self.loader.source_mtime = source_mtime
            # If bytecode is used then EOFError would be raised by marshal.
            self.loader.bytecode = self.loader.bytecode[8:]
            code_object = self.loader.get_code(self.name)
            self.verify_code(code_object, bytecode_written=True)
            self.loader.source_mtime = original

    def test_code_bad_magic(self):
        # Skip over bytecode with a bad magic number.
        self.setUp(magic=b'0000')
        # If bytecode is used then EOFError would be raised by marshal.
        self.loader.bytecode = self.loader.bytecode[8:]
        code_object = self.loader.get_code(self.name)
        self.verify_code(code_object, bytecode_written=True)

    def test_dont_write_bytecode(self):
        # Bytecode is not written if sys.dont_write_bytecode is true.
        # Can assume it is false already thanks to the skipIf class decorator.
        try:
            sys.dont_write_bytecode = True
            self.loader.bytecode_path = "<does not exist>"
            code_object = self.loader.get_code(self.name)
            self.assertNotIn(self.cached, self.loader.written)
        finally:
            sys.dont_write_bytecode = False

    def test_no_set_data(self):
        # If set_data is not defined, one can still read bytecode.
        self.setUp(magic=b'0000')
        original_set_data = self.loader.__class__.set_data
        try:
            del self.loader.__class__.set_data
            code_object = self.loader.get_code(self.name)
            self.verify_code(code_object)
        finally:
            self.loader.__class__.set_data = original_set_data

    def test_set_data_raises_exceptions(self):
        # Raising NotImplementedError or OSError is okay for set_data.
        def raise_exception(exc):
            def closure(*args, **kwargs):
                raise exc
            return closure

        self.setUp(magic=b'0000')
        self.loader.set_data = raise_exception(NotImplementedError)
        code_object = self.loader.get_code(self.name)
        self.verify_code(code_object)


class SourceLoaderGetSourceTests(unittest.TestCase):

    """Tests for importlib.abc.SourceLoader.get_source()."""

    def test_default_encoding(self):
        # Should have no problems with UTF-8 text.
        name = 'mod'
        mock = SourceOnlyLoaderMock('mod.file')
        source = 'x = "ü"'
        mock.source = source.encode('utf-8')
        returned_source = mock.get_source(name)
        self.assertEqual(returned_source, source)

    def test_decoded_source(self):
        # Decoding should work.
        name = 'mod'
        mock = SourceOnlyLoaderMock("mod.file")
        source = "# coding: Latin-1\nx='ü'"
        assert source.encode('latin-1') != source.encode('utf-8')
        mock.source = source.encode('latin-1')
        returned_source = mock.get_source(name)
        self.assertEqual(returned_source, source)

    def test_universal_newlines(self):
        # PEP 302 says universal newlines should be used.
        name = 'mod'
        mock = SourceOnlyLoaderMock('mod.file')
        source = "x = 42\r\ny = -13\r\n"
        mock.source = source.encode('utf-8')
        expect = io.IncrementalNewlineDecoder(None, True).decode(source)
        self.assertEqual(mock.get_source(name), expect)



if __name__ == '__main__':
    unittest.main()