Lib/test/test_import.py

   1 from test_support import TESTFN, TestFailed
   2
   3 import os
   4 import random
   5 import sys
   6
   7 # Brief digression to test that import is case-sensitive:  if we got this
   8 # far, we know for sure that "random" exists.
   9 try:
  10     import RAnDoM
  11 except ImportError:
  12     pass
  13 else:
  14     raise TestFailed("import of RAnDoM should have failed (case mismatch)")
  15
  16 # Another brief digression to test the accuracy of manifest float constants.
  17 import double_const  # don't blink -- that *was* the test
  18
  19 def test_with_extension(ext): # ext normally ".py"; perhaps ".pyw"
  20     source = TESTFN + ext
  21     pyo = TESTFN + os.extsep + "pyo"
  22     if sys.platform.startswith('java'):
  23         pyc = TESTFN + "$py.class"
  24     else:
  25         pyc = TESTFN + os.extsep + "pyc"
  26
  27     f = open(source, "w")
  28     print >> f, "# This tests Python's ability to import a", ext, "file."
  29     a = random.randrange(1000)
  30     b = random.randrange(1000)
  31     print >> f, "a =", a
  32     print >> f, "b =", b
  33     f.close()
  34
  35     try:
  36         try:
  37             mod = __import__(TESTFN)
  38         except ImportError, err:
  39             raise ValueError("import from %s failed: %s" % (ext, err))
  40
  41         if mod.a != a or mod.b != b:
  42             print a, "!=", mod.a
  43             print b, "!=", mod.b
  44             raise ValueError("module loaded (%s) but contents invalid" % mod)
  45     finally:
  46         os.unlink(source)
  47
  48     try:
  49         try:
  50             reload(mod)
  51         except ImportError, err:
  52             raise ValueError("import from .pyc/.pyo failed: %s" % err)
  53     finally:
  54         try:
  55             os.unlink(pyc)
  56         except os.error:
  57             pass
  58         try:
  59             os.unlink(pyo)
  60         except os.error:
  61             pass
  62         del sys.modules[TESTFN]
  63
  64 sys.path.insert(0, os.curdir)
  65 try:
  66     test_with_extension(os.extsep + "py")
  67     if sys.platform.startswith("win"):
  68         for ext in ".PY", ".Py", ".pY", ".pyw", ".PYW", ".pYw":
  69             test_with_extension(ext)
  70 finally:
  71     del sys.path[0]