Lib/test/test_import.py

   1 import unittest
   2 import os
   3 import stat
   4 import random
   5 import shutil
   6 import sys
   7 import py_compile
   8 import warnings
   9 import marshal
  10 from test.test_support import (unlink, TESTFN, unload, run_unittest,
  11     check_warnings, TestFailed, EnvironmentVarGuard)
  12
  13
  14 def remove_files(name):
  15     for f in (name + os.extsep + "py",
  16               name + os.extsep + "pyc",
  17               name + os.extsep + "pyo",
  18               name + os.extsep + "pyw",
  19               name + "$py.class"):
  20         if os.path.exists(f):
  21             os.remove(f)
  22
  23
  24 class ImportTest(unittest.TestCase):
  25
  26     def testCaseSensitivity(self):
  27         # Brief digression to test that import is case-sensitive:  if we got this
  28         # far, we know for sure that "random" exists.
  29         try:
  30             import RAnDoM
  31         except ImportError:
  32             pass
  33         else:
  34             self.fail("import of RAnDoM should have failed (case mismatch)")
  35
  36     def testDoubleConst(self):
  37         # Another brief digression to test the accuracy of manifest float constants.
  38         from test import double_const  # don't blink -- that *was* the test
  39
  40     def testImport(self):
  41         def test_with_extension(ext):
  42             # ext normally ".py"; perhaps ".pyw"
  43             source = TESTFN + ext
  44             pyo = TESTFN + os.extsep + "pyo"
  45             if sys.platform.startswith('java'):
  46                 pyc = TESTFN + "$py.class"
  47             else:
  48                 pyc = TESTFN + os.extsep + "pyc"
  49
  50             f = open(source, "w")
  51             print >> f, "# This tests Python's ability to import a", ext, "file."
  52             a = random.randrange(1000)
  53             b = random.randrange(1000)
  54             print >> f, "a =", a
  55             print >> f, "b =", b
  56             f.close()
  57
  58             try:
  59                 try:
  60                     mod = __import__(TESTFN)
  61                 except ImportError, err:
  62                     self.fail("import from %s failed: %s" % (ext, err))
  63
  64                 self.assertEquals(mod.a, a,
  65                     "module loaded (%s) but contents invalid" % mod)
  66                 self.assertEquals(mod.b, b,
  67                     "module loaded (%s) but contents invalid" % mod)
  68             finally:
  69                 os.unlink(source)
  70
  71             try:
  72                 try:
  73                     reload(mod)
  74                 except ImportError, err:
  75                     self.fail("import from .pyc/.pyo failed: %s" % err)
  76             finally:
  77                 try:
  78                     os.unlink(pyc)
  79                 except OSError:
  80                     pass
  81                 try:
  82                     os.unlink(pyo)
  83                 except OSError:
  84                     pass
  85                 del sys.modules[TESTFN]
  86
  87         sys.path.insert(0, os.curdir)
  88         try:
  89             test_with_extension(os.extsep + "py")
  90             if sys.platform.startswith("win"):
  91                 for ext in ".PY", ".Py", ".pY", ".pyw", ".PYW", ".pYw":
  92                     test_with_extension(ext)
  93         finally:
  94             del sys.path[0]
  95
  96     @unittest.skipUnless(os.name == 'posix', "test meaningful only on posix systems")
  97     def test_execute_bit_not_copied(self):
  98         # Issue 6070: under posix .pyc files got their execute bit set if
  99         # the .py file had the execute bit set, but they aren't executable.
 100         oldmask = os.umask(022)
 101         sys.path.insert(0, os.curdir)
 102         try:
 103             fname = TESTFN + os.extsep + "py"
 104             f = open(fname, 'w').close()
 105             os.chmod(fname, (stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH |
 106                              stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH))
 107             __import__(TESTFN)
 108             fn = fname + 'c'
 109             if not os.path.exists(fn):
 110                 fn = fname + 'o'
 111                 if not os.path.exists(fn): raise TestFailed("__import__ did "
 112                     "not result in creation of either a .pyc or .pyo file")
 113             s = os.stat(fn)
 114             self.assertEquals(stat.S_IMODE(s.st_mode),
 115                               stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH)
 116         finally:
 117             os.umask(oldmask)
 118             remove_files(TESTFN)
 119             if TESTFN in sys.modules: del sys.modules[TESTFN]
 120             del sys.path[0]
 121
 122     def testImpModule(self):
 123         # Verify that the imp module can correctly load and find .py files
 124         import imp, os
 125         # XXX (ncoghlan): It would be nice to use test_support.CleanImport
 126         # here, but that breaks because the os module registers some
 127         # handlers in copy_reg on import. Since CleanImport doesn't
 128         # revert that registration, the module is left in a broken
 129         # state after reversion. Reinitialising the module contents
 130         # and just reverting os.environ to its previous state is an OK
 131         # workaround
 132         orig_path = os.path
 133         orig_getenv = os.getenv
 134         with EnvironmentVarGuard():
 135             x = imp.find_module("os")
 136             new_os = imp.load_module("os", *x)
 137             self.assertIs(os, new_os)
 138             self.assertIs(orig_path, new_os.path)
 139             self.assertIsNot(orig_getenv, new_os.getenv)
 140
 141     def test_module_with_large_stack(self, module='longlist'):
 142         # create module w/list of 65000 elements to test bug #561858
 143         filename = module + os.extsep + 'py'
 144
 145         # create a file with a list of 65000 elements
 146         f = open(filename, 'w+')
 147         f.write('d = [\n')
 148         for i in range(65000):
 149             f.write('"",\n')
 150         f.write(']')
 151         f.close()
 152
 153         # compile & remove .py file, we only need .pyc (or .pyo)
 154         f = open(filename, 'r')
 155         py_compile.compile(filename)
 156         f.close()
 157         os.unlink(filename)
 158
 159         # need to be able to load from current dir
 160         sys.path.append('')
 161
 162         # this used to crash
 163         exec 'import ' + module
 164
 165         # cleanup
 166         del sys.path[-1]
 167         for ext in 'pyc', 'pyo':
 168             fname = module + os.extsep + ext
 169             if os.path.exists(fname):
 170                 os.unlink(fname)
 171
 172     def test_failing_import_sticks(self):
 173         source = TESTFN + os.extsep + "py"
 174         f = open(source, "w")
 175         print >> f, "a = 1/0"
 176         f.close()
 177
 178         # New in 2.4, we shouldn't be able to import that no matter how often
 179         # we try.
 180         sys.path.insert(0, os.curdir)
 181         try:
 182             for i in 1, 2, 3:
 183                 try:
 184                     mod = __import__(TESTFN)
 185                 except ZeroDivisionError:
 186                     if TESTFN in sys.modules:
 187                         self.fail("damaged module in sys.modules on %i. try" % i)
 188                 else:
 189                     self.fail("was able to import a damaged module on %i. try" % i)
 190         finally:
 191             sys.path.pop(0)
 192             remove_files(TESTFN)
 193
 194     def test_failing_reload(self):
 195         # A failing reload should leave the module object in sys.modules.
 196         source = TESTFN + os.extsep + "py"
 197         f = open(source, "w")
 198         print >> f, "a = 1"
 199         print >> f, "b = 2"
 200         f.close()
 201
 202         sys.path.insert(0, os.curdir)
 203         try:
 204             mod = __import__(TESTFN)
 205             self.assertTrue(TESTFN in sys.modules, "expected module in sys.modules")
 206             self.assertEquals(mod.a, 1, "module has wrong attribute values")
 207             self.assertEquals(mod.b, 2, "module has wrong attribute values")
 208
 209             # On WinXP, just replacing the .py file wasn't enough to
 210             # convince reload() to reparse it.  Maybe the timestamp didn't
 211             # move enough.  We force it to get reparsed by removing the
 212             # compiled file too.
 213             remove_files(TESTFN)
 214
 215             # Now damage the module.
 216             f = open(source, "w")
 217             print >> f, "a = 10"
 218             print >> f, "b = 20//0"
 219             f.close()
 220
 221             self.assertRaises(ZeroDivisionError, reload, mod)
 222
 223             # But we still expect the module to be in sys.modules.
 224             mod = sys.modules.get(TESTFN)
 225             self.assertFalse(mod is None, "expected module to still be in sys.modules")
 226
 227             # We should have replaced a w/ 10, but the old b value should
 228             # stick.
 229             self.assertEquals(mod.a, 10, "module has wrong attribute values")
 230             self.assertEquals(mod.b, 2, "module has wrong attribute values")
 231
 232         finally:
 233             sys.path.pop(0)
 234             remove_files(TESTFN)
 235             if TESTFN in sys.modules:
 236                 del sys.modules[TESTFN]
 237
 238     def test_infinite_reload(self):
 239         # Bug #742342 reports that Python segfaults (infinite recursion in C)
 240         #  when faced with self-recursive reload()ing.
 241
 242         sys.path.insert(0, os.path.dirname(__file__))
 243         try:
 244             import infinite_reload
 245         finally:
 246             sys.path.pop(0)
 247
 248     def test_import_name_binding(self):
 249         # import x.y.z binds x in the current namespace
 250         import test as x
 251         import test.test_support
 252         self.assertTrue(x is test, x.__name__)
 253         self.assertTrue(hasattr(test.test_support, "__file__"))
 254
 255         # import x.y.z as w binds z as w
 256         import test.test_support as y
 257         self.assertTrue(y is test.test_support, y.__name__)
 258
 259     def test_import_initless_directory_warning(self):
 260         with warnings.catch_warnings():
 261             # Just a random non-package directory we always expect to be
 262             # somewhere in sys.path...
 263             warnings.simplefilter('error', ImportWarning)
 264             self.assertRaises(ImportWarning, __import__, "site-packages")
 265
 266     def test_importbyfilename(self):
 267         path = os.path.abspath(TESTFN)
 268         try:
 269             __import__(path)
 270         except ImportError, err:
 271             self.assertEqual("Import by filename is not supported.",
 272                               err.args[0])
 273         else:
 274             self.fail("import by path didn't raise an exception")
 275
 276
 277 class TestPycRewriting(unittest.TestCase):
 278     # Test that the `co_filename` attribute on code objects always points
 279     # to the right file, even when various things happen (e.g. both the .py
 280     # and the .pyc file are renamed).
 281
 282     module_name = "unlikely_module_name"
 283     module_source = """
 284 import sys
 285 code_filename = sys._getframe().f_code.co_filename
 286 module_filename = __file__
 287 constant = 1
 288 def func():
 289     pass
 290 func_filename = func.func_code.co_filename
 291 """
 292     dir_name = os.path.abspath(TESTFN)
 293     file_name = os.path.join(dir_name, module_name) + os.extsep + "py"
 294     compiled_name = file_name + ("c" if __debug__ else "o")
 295
 296     def setUp(self):
 297         self.sys_path = sys.path[:]
 298         self.orig_module = sys.modules.pop(self.module_name, None)
 299         os.mkdir(self.dir_name)
 300         with open(self.file_name, "w") as f:
 301             f.write(self.module_source)
 302         sys.path.insert(0, self.dir_name)
 303
 304     def tearDown(self):
 305         sys.path[:] = self.sys_path
 306         if self.orig_module is not None:
 307             sys.modules[self.module_name] = self.orig_module
 308         else:
 309             del sys.modules[self.module_name]
 310         for file_name in self.file_name, self.compiled_name:
 311             if os.path.exists(file_name):
 312                 os.remove(file_name)
 313         if os.path.exists(self.dir_name):
 314             shutil.rmtree(self.dir_name)
 315
 316     def import_module(self):
 317         ns = globals()
 318         __import__(self.module_name, ns, ns)
 319         return sys.modules[self.module_name]
 320
 321     def test_basics(self):
 322         mod = self.import_module()
 323         self.assertEqual(mod.module_filename, self.file_name)
 324         self.assertEqual(mod.code_filename, self.file_name)
 325         self.assertEqual(mod.func_filename, self.file_name)
 326         del sys.modules[self.module_name]
 327         mod = self.import_module()
 328         self.assertEqual(mod.module_filename, self.compiled_name)
 329         self.assertEqual(mod.code_filename, self.file_name)
 330         self.assertEqual(mod.func_filename, self.file_name)
 331
 332     def test_incorrect_code_name(self):
 333         py_compile.compile(self.file_name, dfile="another_module.py")
 334         mod = self.import_module()
 335         self.assertEqual(mod.module_filename, self.compiled_name)
 336         self.assertEqual(mod.code_filename, self.file_name)
 337         self.assertEqual(mod.func_filename, self.file_name)
 338
 339     def test_module_without_source(self):
 340         target = "another_module.py"
 341         py_compile.compile(self.file_name, dfile=target)
 342         os.remove(self.file_name)
 343         mod = self.import_module()
 344         self.assertEqual(mod.module_filename, self.compiled_name)
 345         self.assertEqual(mod.code_filename, target)
 346         self.assertEqual(mod.func_filename, target)
 347
 348     def test_foreign_code(self):
 349         py_compile.compile(self.file_name)
 350         with open(self.compiled_name, "rb") as f:
 351             header = f.read(8)
 352             code = marshal.load(f)
 353         constants = list(code.co_consts)
 354         foreign_code = test_main.func_code
 355         pos = constants.index(1)
 356         constants[pos] = foreign_code
 357         code = type(code)(code.co_argcount, code.co_nlocals, code.co_stacksize,
 358                           code.co_flags, code.co_code, tuple(constants),
 359                           code.co_names, code.co_varnames, code.co_filename,
 360                           code.co_name, code.co_firstlineno, code.co_lnotab,
 361                           code.co_freevars, code.co_cellvars)
 362         with open(self.compiled_name, "wb") as f:
 363             f.write(header)
 364             marshal.dump(code, f)
 365         mod = self.import_module()
 366         self.assertEqual(mod.constant.co_filename, foreign_code.co_filename)
 367
 368 class PathsTests(unittest.TestCase):
 369     path = TESTFN
 370
 371     def setUp(self):
 372         os.mkdir(self.path)
 373         self.syspath = sys.path[:]
 374
 375     def tearDown(self):
 376         shutil.rmtree(self.path)
 377         sys.path[:] = self.syspath
 378
 379     # http://bugs.python.org/issue1293
 380     def test_trailing_slash(self):
 381         f = open(os.path.join(self.path, 'test_trailing_slash.py'), 'w')
 382         f.write("testdata = 'test_trailing_slash'")
 383         f.close()
 384         sys.path.append(self.path+'/')
 385         mod = __import__("test_trailing_slash")
 386         self.assertEqual(mod.testdata, 'test_trailing_slash')
 387         unload("test_trailing_slash")
 388
 389     # http://bugs.python.org/issue3677
 390     def _test_UNC_path(self):
 391         f = open(os.path.join(self.path, 'test_trailing_slash.py'), 'w')
 392         f.write("testdata = 'test_trailing_slash'")
 393         f.close()
 394         #create the UNC path, like \\myhost\c$\foo\bar
 395         path = os.path.abspath(self.path)
 396         import socket
 397         hn = socket.gethostname()
 398         drive = path[0]
 399         unc = "\\\\%s\\%s$"%(hn, drive)
 400         unc += path[2:]
 401         sys.path.append(path)
 402         mod = __import__("test_trailing_slash")
 403         self.assertEqual(mod.testdata, 'test_trailing_slash')
 404         unload("test_trailing_slash")
 405
 406     if sys.platform == "win32":
 407         test_UNC_path = _test_UNC_path
 408
 409
 410 class RelativeImport(unittest.TestCase):
 411     def tearDown(self):
 412         try:
 413             del sys.modules["test.relimport"]
 414         except:
 415             pass
 416
 417     def test_relimport_star(self):
 418         # This will import * from .test_import.
 419         from . import relimport
 420         self.assertTrue(hasattr(relimport, "RelativeImport"))
 421
 422     def test_issue3221(self):
 423         def check_absolute():
 424             exec "from os import path" in ns
 425         def check_relative():
 426             exec "from . import relimport" in ns
 427         # Check both OK with __package__ and __name__ correct
 428         ns = dict(__package__='test', __name__='test.notarealmodule')
 429         check_absolute()
 430         check_relative()
 431         # Check both OK with only __name__ wrong
 432         ns = dict(__package__='test', __name__='notarealpkg.notarealmodule')
 433         check_absolute()
 434         check_relative()
 435         # Check relative fails with only __package__ wrong
 436         ns = dict(__package__='foo', __name__='test.notarealmodule')
 437         with check_warnings() as w:
 438             check_absolute()
 439             self.assertTrue('foo' in str(w.message))
 440             self.assertEqual(w.category, RuntimeWarning)
 441         self.assertRaises(SystemError, check_relative)
 442         # Check relative fails with __package__ and __name__ wrong
 443         ns = dict(__package__='foo', __name__='notarealpkg.notarealmodule')
 444         with check_warnings() as w:
 445             check_absolute()
 446             self.assertTrue('foo' in str(w.message))
 447             self.assertEqual(w.category, RuntimeWarning)
 448         self.assertRaises(SystemError, check_relative)
 449         # Check both fail with package set to a non-string
 450         ns = dict(__package__=object())
 451         self.assertRaises(ValueError, check_absolute)
 452         self.assertRaises(ValueError, check_relative)
 453
 454 def test_main(verbose=None):
 455     run_unittest(ImportTest, TestPycRewriting, PathsTests, RelativeImport)
 456
 457 if __name__ == '__main__':
 458     # test needs to be a package, so we can do relative import
 459     from test.test_import import test_main
 460     test_main()