[Python-checkins] python/dist/src/Lib/test test_import.py, 1.18, 1.19

[tim_one at users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Lib/test
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv23540/Lib/test

Modified Files:
	test_import.py 
Log Message:
New tests:
    test_failing_import_sticks -- if an import raises an exception,
        ensure that trying to import it again continues raising exceptions
    test_failing_reload -- if a module loads OK, but a reload raises an
        exception, ensure that the module is still in sys.modules, and
        that its __dict__ reflects as much of the reload attempt as
        succeeded.  That doesn't seem like sane semantics, but it is
        backward-compatible semantics <wink>.


Index: test_import.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/test/test_import.py,v
retrieving revision 1.18
retrieving revision 1.19
diff -C2 -d -r1.18 -r1.19
*** test_import.py	10 May 2003 07:36:55 -0000	1.18
--- test_import.py	2 Aug 2004 03:58:27 -0000	1.19
***************
*** 18,21 ****
--- 18,30 ----
  import double_const  # don't blink -- that *was* the test
  
+ def remove_files(name):
+     for f in (name + os.extsep + "py",
+               name + os.extsep + "pyc",
+               name + os.extsep + "pyo",
+               name + os.extsep + "pyw",
+               name + "$py.class"):
+         if os.path.exists(f):
+             os.remove(f)
+ 
  def test_with_extension(ext): # ext normally ".py"; perhaps ".pyw"
      source = TESTFN + ext
***************
*** 109,110 ****
--- 118,194 ----
  
  test_module_with_large_stack('longlist')
+ 
+ def test_failing_import_sticks():
+     source = TESTFN + os.extsep + "py"
+     f = open(source, "w")
+     print >> f, "a = 1/0"
+     f.close()
+ 
+     # New in 2.4, we shouldn't be able to import that no matter how often
+     # we try.
+     sys.path.insert(0, os.curdir)
+     try:
+         for i in 1, 2, 3:
+             try:
+                 mod = __import__(TESTFN)
+             except ZeroDivisionError:
+                 if TESTFN in sys.modules:
+                     raise TestFailed("damaged module in sys.modules", i)
+             else:
+                 raise TestFailed("was able to import a damaged module", i)
+     finally:
+         sys.path.pop(0)
+         remove_files(TESTFN)
+ 
+ test_failing_import_sticks()
+ 
+ def test_failing_reload():
+     # A failing reload should leave the module object in sys.modules.
+     source = TESTFN + os.extsep + "py"
+     f = open(source, "w")
+     print >> f, "a = 1"
+     print >> f, "b = 2"
+     f.close()
+ 
+     sys.path.insert(0, os.curdir)
+     try:
+         mod = __import__(TESTFN)
+         if TESTFN not in sys.modules:
+             raise TestFailed("expected module in sys.modules")
+         if mod.a != 1 or mod.b != 2:
+             raise TestFailed("module has wrong attribute values")
+ 
+         # On WinXP, just replacing the .py file wasn't enough to
+         # convince reload() to reparse it.  Maybe the timestamp didn't
+         # move enough.  We force it to get reparsed by removing the
+         # compiled file too.
+         remove_files(TESTFN)
+ 
+         # Now damage the module.
+         f = open(source, "w")
+         print >> f, "a = 10"
+         print >> f, "b = 20//0"
+         f.close()
+         try:
+             reload(mod)
+         except ZeroDivisionError:
+             pass
+         else:
+             raise TestFailed("was able to reload a damaged module")
+ 
+         # But we still expect the module to be in sys.modules.
+         mod = sys.modules.get(TESTFN)
+         if mod is None:
+             raise TestFailed("expected module to still be in sys.modules")
+         # We should have replaced a w/ 10, but the old b value should
+         # stick.
+         if mod.a != 10 or mod.b != 2:
+             raise TestFailed("module has wrong attribute values")
+ 
+     finally:
+         sys.path.pop(0)
+         remove_files(TESTFN)
+         if TESTFN in sys.modules:
+             del sys.modules[TESTFN]
+ 
+ test_failing_reload()