svn_fs.py unit-tests fail with Subversion 1.6.1 on Windows

[cboos]

There's a new SQLite database in the repository (db/rep-cache.db) which is apparently still opened by the Subversion code at the time we try to rmtree the repository.

I haven't managed to force the removal.
Maybe it's a SVN issue, maybe it's the way we use the API... let's see if the issue persists with 1.6.2.

The first time the tests are executed, we get this error:

WindowsError: [Error 32] The process cannot access the file because it is being used by another process: 'c:\\users\\cboos\\appdata\\local\\temp\\trac-svnrepos\\db\\rep-cache.db'

The second time, we get that other error:

svn.core.SubversionException: ("'c:\\users\\cboos\\appdata\\local\\temp\\trac-svnrepos' is a subdirectory of an existing repository rooted at 'c:\\users\\cboos\\appdata\\local\\temp\\trac-svnrepos'", 165002)

(which is somehow normal, as the trac-svnrepos from the previous run is still there)

[cboos]

Added a redirection to this ticket from the code in r8192, in case someone else gets hit by this problem.

... and adding David to the loop in case he has some insight (hope you don't mind ;-) ).

[cboos]

Same issue with 1.6.2.

[cboos]

Related: ​http://svn.haxx.se/dev/archive-2009-05/0061.shtml

We however already cleared the self.repos in the tearDown methods, so it's still not obvious what to do.

[cboos]

Hm, it was due to our own Pool stuff, fixed in r8209.

By the way, the Subversion python bindings do their own automatic pool management since 1.4.x (or even earlier?), so maybe it's time to simplify things in this area...

Two other things that seem also perfectible:

• calling core.apr_terminate() in SubversionRepositoryTestSetup.setUp doesn't seem right (An APR program must call this function at termination once it has stopped using APR services. from ​apr_terminate API)
• in SubversionRepositoryTestSetup.tearDown, repos.delete(REPOS_PATH) would be simpler (idea stolen from the tests for the Subversion SWIG python bindings...)

[cboos]

(a follow-up was needed, see r8212 - thanks Remy for noticing the problem)

[cboos]

With a new install (Python 2.7.2, svn 1.6.15, Windows 7), I have again similar errors, like:

  File "c:\Trac\repos\trunk\trac\versioncontrol\tests\svn_fs.py", line 86, in tearDown
    shutil.rmtree(REPOS_PATH)
  File "C:\Dev\Python272\lib\shutil.py", line 244, in rmtree
    rmtree(fullname, ignore_errors, onerror)
  File "C:\Dev\Python272\lib\shutil.py", line 244, in rmtree
    rmtree(fullname, ignore_errors, onerror)
  File "C:\Dev\Python272\lib\shutil.py", line 244, in rmtree
    rmtree(fullname, ignore_errors, onerror)
  File "C:\Dev\Python272\lib\shutil.py", line 249, in rmtree
    onerror(os.remove, fullname, sys.exc_info())
  File "C:\Dev\Python272\lib\shutil.py", line 247, in rmtree
    os.remove(fullname)
WindowsError: [Error 5] Access is denied: 'c:\\users\\cboos\\appdata\\local\\temp\\trac-svnrepos\\db\\revs\\0\\0'

The following "strengthening" of rmtree in tearDown() fixes it:

svn_fs.py

@@ -79 +79 @@
         if os.name == 'nt':
             # The Windows version of 'shutil.rmtree' doesn't override the
             # permissions of read-only files, so we have to do it ourselves:
-            format_file = os.path.join(REPOS_PATH, 'db', 'format')
-            if os.path.isfile(format_file):
-                os.chmod(format_file, stat.S_IRWXU)
-            os.chmod(os.path.join(REPOS_PATH, 'format'), stat.S_IRWXU)
-        shutil.rmtree(REPOS_PATH)
+            def retry_remove(fn, path, excinfo):
+                if path.startswith(REPOS_PATH): # safety check
+                    if os.path.isfile(path):
+                        os.chmod(path, stat.S_IRWXU)
+                    fn(path) # 2nd try
+        shutil.rmtree(REPOS_PATH, onerror=retry_remove)
 
 
 # -- Re-usable test mixins

But it seems even better to use the svn API for this, hence the final fix in r10794.