[Python-checkins] cpython (2.7): Fix #15496. Add directory removal helpers to make Windows tests more reliable.

[brian.curtin]

http://hg.python.org/cpython/rev/c863dadc65eb
changeset:   78554:c863dadc65eb
branch:      2.7
parent:      78550:3bddc965e2ea
user:        Brian Curtin <brian at python.org>
date:        Mon Aug 13 17:26:48 2012 -0500
summary:
  Fix #15496. Add directory removal helpers to make Windows tests more reliable. Patch by Jeremy Kloth

files:
  Lib/test/test_support.py |  68 +++++++++++++++++++++++++++-
  Misc/NEWS                |   3 +
  2 files changed, 69 insertions(+), 2 deletions(-)


diff --git a/Lib/test/test_support.py b/Lib/test/test_support.py
--- a/Lib/test/test_support.py
+++ b/Lib/test/test_support.py
@@ -181,15 +181,79 @@
     except KeyError:
         pass
 
+if sys.platform.startswith("win"):
+    def _waitfor(func, pathname, waitall=False):
+        # Peform the operation
+        func(pathname)
+        # Now setup the wait loop
+        if waitall:
+            dirname = pathname
+        else:
+            dirname, name = os.path.split(pathname)
+            dirname = dirname or '.'
+        # Check for `pathname` to be removed from the filesystem.
+        # The exponential backoff of the timeout amounts to a total
+        # of ~1 second after which the deletion is probably an error
+        # anyway.
+        # Testing on a i7 at 4.3GHz shows that usually only 1 iteration is
+        # required when contention occurs.
+        timeout = 0.001
+        while timeout < 1.0:
+            # Note we are only testing for the existance of the file(s) in
+            # the contents of the directory regardless of any security or
+            # access rights.  If we have made it this far, we have sufficient
+            # permissions to do that much using Python's equivalent of the
+            # Windows API FindFirstFile.
+            # Other Windows APIs can fail or give incorrect results when
+            # dealing with files that are pending deletion.
+            L = os.listdir(dirname)
+            if not (L if waitall else name in L):
+                return
+            # Increase the timeout and try again
+            time.sleep(timeout)
+            timeout *= 2
+        warnings.warn('tests may fail, delete still pending for ' + pathname,
+                      RuntimeWarning, stacklevel=4)
+
+    def _unlink(filename):
+        _waitfor(os.unlink, filename)
+
+    def _rmdir(dirname):
+        _waitfor(os.rmdir, dirname)
+
+    def _rmtree(path):
+        def _rmtree_inner(path):
+            for name in os.listdir(path):
+                fullname = os.path.join(path, name)
+                if os.path.isdir(fullname):
+                    _waitfor(_rmtree_inner, fullname, waitall=True)
+                    os.rmdir(fullname)
+                else:
+                    os.unlink(fullname)
+        _waitfor(_rmtree_inner, path, waitall=True)
+        _waitfor(os.rmdir, path)
+else:
+    _unlink = os.unlink
+    _rmdir = os.rmdir
+    _rmtree = shutil.rmtree
+
 def unlink(filename):
     try:
-        os.unlink(filename)
+        _unlink(filename)
     except OSError:
         pass
 
+def rmdir(dirname):
+    try:
+        _rmdir(dirname)
+    except OSError as error:
+        # The directory need not exist.
+        if error.errno != errno.ENOENT:
+            raise
+
 def rmtree(path):
     try:
-        shutil.rmtree(path)
+        _rmtree(path)
     except OSError, e:
         # Unix returns ENOENT, Windows returns ESRCH.
         if e.errno not in (errno.ENOENT, errno.ESRCH):
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -323,6 +323,9 @@
 Tests
 -----
 
+- Issue #15496: Add directory removal helpers for tests on Windows.
+  Patch by Jeremy Kloth.
+
 - Issue #15043: test_gdb is now skipped entirely if gdb security settings
   block loading of the gdb hooks
 

-- 
Repository URL: http://hg.python.org/cpython