blackbox: fix type error on log rotation on read-only filesystem

Grepping around, the code uses either encoding.strtolocal or
stringutil.forcebytestr in this situation. No idea which is best.

Differential Revision: https://phab.mercurial-scm.org/D10293

mercurial/loggingutil.py

@@ -1,141 +1,144 b''
 # loggingutil.py - utility for logging events
 #
 # Copyright 2010 Nicolas Dumazet
 # Copyright 2013 Facebook, Inc.
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import errno
 
-from . import pycompat
+from . import (
+    encoding,
+    pycompat,
+)
 
 from .utils import (
     dateutil,
     procutil,
     stringutil,
 )
 
 
 def openlogfile(ui, vfs, name, maxfiles=0, maxsize=0):
     """Open log file in append mode, with optional rotation
 
     If maxsize > 0, the log file will be rotated up to maxfiles.
     """
 
     def rotate(oldpath, newpath):
         try:
             vfs.unlink(newpath)
         except OSError as err:
             if err.errno != errno.ENOENT:
                 ui.debug(
                     b"warning: cannot remove '%s': %s\n"
-                    % (newpath, err.strerror)
+                    % (newpath, encoding.strtolocal(err.strerror))
                 )
         try:
             if newpath:
                 vfs.rename(oldpath, newpath)
         except OSError as err:
             if err.errno != errno.ENOENT:
                 ui.debug(
                     b"warning: cannot rename '%s' to '%s': %s\n"
-                    % (newpath, oldpath, err.strerror)
+                    % (newpath, oldpath, encoding.strtolocal(err.strerror))
                 )
 
     if maxsize > 0:
         try:
             st = vfs.stat(name)
         except OSError:
             pass
         else:
             if st.st_size >= maxsize:
                 path = vfs.join(name)
                 for i in pycompat.xrange(maxfiles - 1, 1, -1):
                     rotate(
                         oldpath=b'%s.%d' % (path, i - 1),
                         newpath=b'%s.%d' % (path, i),
                     )
                 rotate(oldpath=path, newpath=maxfiles > 0 and path + b'.1')
     return vfs(name, b'a', makeparentdirs=False)
 
 
 def _formatlogline(msg):
     date = dateutil.datestr(format=b'%Y/%m/%d %H:%M:%S')
     pid = procutil.getpid()
     return b'%s (%d)> %s' % (date, pid, msg)
 
 
 def _matchevent(event, tracked):
     return b'*' in tracked or event in tracked
 
 
 class filelogger(object):
     """Basic logger backed by physical file with optional rotation"""
 
     def __init__(self, vfs, name, tracked, maxfiles=0, maxsize=0):
         self._vfs = vfs
         self._name = name
         self._trackedevents = set(tracked)
         self._maxfiles = maxfiles
         self._maxsize = maxsize
 
     def tracked(self, event):
         return _matchevent(event, self._trackedevents)
 
     def log(self, ui, event, msg, opts):
         line = _formatlogline(msg)
         try:
             with openlogfile(
                 ui,
                 self._vfs,
                 self._name,
                 maxfiles=self._maxfiles,
                 maxsize=self._maxsize,
             ) as fp:
                 fp.write(line)
         except IOError as err:
             ui.debug(
                 b'cannot write to %s: %s\n'
                 % (self._name, stringutil.forcebytestr(err))
             )
 
 
 class fileobjectlogger(object):
     """Basic logger backed by file-like object"""
 
     def __init__(self, fp, tracked):
         self._fp = fp
         self._trackedevents = set(tracked)
 
     def tracked(self, event):
         return _matchevent(event, self._trackedevents)
 
     def log(self, ui, event, msg, opts):
         line = _formatlogline(msg)
         try:
             self._fp.write(line)
             self._fp.flush()
         except IOError as err:
             ui.debug(
                 b'cannot write to %s: %s\n'
                 % (
                     stringutil.forcebytestr(self._fp.name),
                     stringutil.forcebytestr(err),
                 )
             )
 
 
 class proxylogger(object):
     """Forward log events to another logger to be set later"""
 
     def __init__(self):
         self.logger = None
 
     def tracked(self, event):
         return self.logger is not None and self.logger.tracked(event)
 
     def log(self, ui, event, msg, opts):
         assert self.logger is not None
         self.logger.log(ui, event, msg, opts)

tests/test-blackbox.t

@@ -1,488 +1,499 b''
 setup
 
   $ cat > myextension.py <<EOF
   > from mercurial import error, registrar
   > cmdtable = {}
   > command = registrar.command(cmdtable)
   > @command(b'crash', [], b'hg crash')
   > def crash(ui, *args, **kwargs):
   >     raise Exception("oops")
   > @command(b'abortcmd', [], b'hg abortcmd')
   > def abort(ui, *args, **kwargs):
   >     raise error.Abort(b"oops")
   > EOF
   $ abspath=`pwd`/myextension.py
 
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > blackbox=
   > mock=$TESTDIR/mockblackbox.py
   > mq=
   > myextension=$TESTTMP/myextension.py
   > [alias]
   > confuse = log --limit 3
   > so-confusing = confuse --style compact
   > EOF
 
   $ hg init blackboxtest
   $ cd blackboxtest
 
 command, exit codes, and duration
 
   $ echo a > a
   $ hg add a
   $ hg blackbox --config blackbox.dirty=True
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> init blackboxtest exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> add a
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> add a exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000+ (5000)> blackbox --config *blackbox.dirty=True* (glob)
 
 failure exit code
   $ rm ./.hg/blackbox.log
   $ hg add non-existent
   non-existent: $ENOENT$
   [1]
   $ hg blackbox
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> add non-existent
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> add non-existent exited 1 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox
 
 abort exit code
   $ rm ./.hg/blackbox.log
   $ hg abortcmd 2> /dev/null
   [255]
   $ hg blackbox -l 2
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> abortcmd exited 255 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox -l 2
 
 unhandled exception
   $ rm ./.hg/blackbox.log
 #if chg
  (chg exits 255 because it fails to receive an exit code)
   $ hg crash 2>/dev/null
   [255]
 #else
  (hg exits 1 because Python default exit code for uncaught exception is 1)
   $ hg crash 2>/dev/null
   [1]
 #endif
   $ hg blackbox -l 2
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> crash exited 1 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox -l 2
 
 alias expansion is logged
   $ rm ./.hg/blackbox.log
   $ hg confuse
   $ hg blackbox
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> confuse
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> alias 'confuse' expands to 'log --limit 3'
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> confuse exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox
 
 recursive aliases work correctly
   $ rm ./.hg/blackbox.log
   $ hg so-confusing
   $ hg blackbox
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> so-confusing
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> alias 'so-confusing' expands to 'confuse --style compact'
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> alias 'confuse' expands to 'log --limit 3'
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> so-confusing exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox
 
 custom date format
   $ rm ./.hg/blackbox.log
   $ hg --config blackbox.date-format='%Y-%m-%d @ %H:%M:%S' \
   >    --config devel.default-date='1334347993 0' --traceback status
   A a
   $ hg blackbox
   2012-04-13 @ 20:13:13 bob @0000000000000000000000000000000000000000 (5000)> --config *blackbox.date-format=%Y-%m-%d @ %H:%M:%S* --config *devel.default-date=1334347993 0* --traceback status (glob)
   2012-04-13 @ 20:13:13 bob @0000000000000000000000000000000000000000 (5000)> --config *blackbox.date-format=%Y-%m-%d @ %H:%M:%S* --config *devel.default-date=1334347993 0* --traceback status exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox
 
 incoming change tracking
 
 create two heads to verify that we only see one change in the log later
   $ hg commit -ma
   $ hg up null
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ echo b > b
   $ hg commit -Amb
   adding b
   created new head
 
 clone, commit, pull
   $ hg clone . ../blackboxtest2
   updating to branch default
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo c > c
   $ hg commit -Amc
   adding c
   $ cd ../blackboxtest2
   $ hg pull
   pulling from $TESTTMP/blackboxtest
   searching for changes
   adding changesets
   adding manifests
   adding file changes
   added 1 changesets with 1 changes to 1 files
   new changesets d02f48003e62
   (run 'hg update' to get a working copy)
   $ hg blackbox -l 6
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> wrote branch cache (served) with 1 labels and 2 nodes
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> updated branch cache (served.hidden) in * seconds (glob)
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> wrote branch cache (served.hidden) with 1 labels and 2 nodes
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> 1 incoming changes - new heads: d02f48003e62
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> pull exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> blackbox -l 6
 
 we must not cause a failure if we cannot write to the log
 
   $ hg rollback
   repository tip rolled back to revision 1 (undo pull)
 
   $ mv .hg/blackbox.log .hg/blackbox.log-
   $ mkdir .hg/blackbox.log
   $ hg --debug incoming
   warning: cannot write to blackbox.log: * (glob)
   comparing with $TESTTMP/blackboxtest
   query 1; heads
   searching for changes
   all local changesets known remotely
   changeset:   2:d02f48003e62c24e2659d97d30f2a83abe5d5d51
   tag:         tip
   phase:       draft
   parent:      1:6563da9dcf87b1949716e38ff3e3dfaa3198eb06
   parent:      -1:0000000000000000000000000000000000000000
   manifest:    2:ab9d46b053ebf45b7996f2922b9893ff4b63d892
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   files+:      c
   extra:       branch=default
   description:
   c
   
   
   $ hg pull
   pulling from $TESTTMP/blackboxtest
   searching for changes
   adding changesets
   adding manifests
   adding file changes
   added 1 changesets with 1 changes to 1 files
   new changesets d02f48003e62
   (run 'hg update' to get a working copy)
 
 a failure reading from the log is fatal
 
   $ hg blackbox -l 3
   abort: *$TESTTMP/blackboxtest2/.hg/blackbox.log* (glob)
   [255]
 
   $ rmdir .hg/blackbox.log
   $ mv .hg/blackbox.log- .hg/blackbox.log
 
 backup bundles get logged
 
   $ touch d
   $ hg commit -Amd
   adding d
   created new head
   $ hg strip tip
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/blackboxtest2/.hg/strip-backup/*-backup.hg (glob)
   $ hg blackbox -l 6
   1970/01/01 00:00:00 bob @73f6ee326b27d820b0472f1a825e3a50f3dc489b (5000)> strip tip
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> saved backup bundle to $TESTTMP/blackboxtest2/.hg/strip-backup/73f6ee326b27-7612e004-backup.hg
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> updated branch cache (immutable) in * seconds (glob)
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> wrote branch cache (immutable) with 1 labels and 2 nodes
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> strip tip exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> blackbox -l 6
 
 extension and python hooks - use the eol extension for a pythonhook
 
   $ echo '[extensions]' >> .hg/hgrc
   $ echo 'eol=' >> .hg/hgrc
   $ echo '[hooks]' >> .hg/hgrc
   $ echo 'update = echo hooked' >> .hg/hgrc
   $ hg update
   The fsmonitor extension is incompatible with the eol extension and has been disabled. (fsmonitor !)
   hooked
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   updated to "d02f48003e62: c"
   1 other heads for branch "default"
   $ cat >> .hg/hgrc <<EOF
   > [extensions]
   > # disable eol, because it is not needed for subsequent tests
   > # (in addition, keeping it requires extra care for fsmonitor)
   > eol=!
   > EOF
   $ hg blackbox -l 5
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> update (no-chg !)
   1970/01/01 00:00:00 bob @6563da9dcf87b1949716e38ff3e3dfaa3198eb06 (5000)> pythonhook-preupdate: hgext.eol.preupdate finished in * seconds (glob)
   1970/01/01 00:00:00 bob @d02f48003e62c24e2659d97d30f2a83abe5d5d51 (5000)> exthook-update: echo hooked finished in * seconds (glob)
   1970/01/01 00:00:00 bob @d02f48003e62c24e2659d97d30f2a83abe5d5d51 (5000)> update exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @d02f48003e62c24e2659d97d30f2a83abe5d5d51 (5000)> serve --cmdserver chgunix --address $TESTTMP.chgsock/server.* --daemon-postexec 'chdir:/' (glob) (chg !)
   1970/01/01 00:00:00 bob @d02f48003e62c24e2659d97d30f2a83abe5d5d51 (5000)> blackbox -l 5
 
 log rotation
 
   $ echo '[blackbox]' >> .hg/hgrc
   $ echo 'maxsize = 20 b' >> .hg/hgrc
   $ echo 'maxfiles = 3' >> .hg/hgrc
   $ hg status
   $ hg status
   $ hg status
   $ hg tip -q
   2:d02f48003e62
   $ ls .hg/blackbox.log*
   .hg/blackbox.log
   .hg/blackbox.log.1
   .hg/blackbox.log.2
   $ cd ..
 
   $ hg init blackboxtest3
   $ cd blackboxtest3
   $ hg blackbox
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> init blackboxtest3 exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> blackbox
   $ mv .hg/blackbox.log .hg/blackbox.log-
   $ mkdir .hg/blackbox.log
   $ sed -e 's/\(.*test1.*\)/#\1/; s#\(.*commit2.*\)#os.rmdir(".hg/blackbox.log")\
   > os.rename(".hg/blackbox.log-", ".hg/blackbox.log")\
   > \1#' $TESTDIR/test-dispatch.py > ../test-dispatch.py
   $ "$PYTHON" $TESTDIR/blackbox-readonly-dispatch.py
   running: --debug add foo
   warning: cannot write to blackbox.log: Is a directory (no-windows !)
   warning: cannot write to blackbox.log: $TESTTMP/blackboxtest3/.hg/blackbox.log: Access is denied (windows !)
   adding foo
   result: 0
   running: --debug commit -m commit1 -d 2000-01-01 foo
   warning: cannot write to blackbox.log: Is a directory (no-windows !)
   warning: cannot write to blackbox.log: $TESTTMP/blackboxtest3/.hg/blackbox.log: Access is denied (windows !)
   committing files:
   foo
   committing manifest
   committing changelog
   updating the branch cache
   committed changeset 0:0e46349438790c460c5c9f7546bfcd39b267bbd2
   result: 0
   running: --debug commit -m commit2 -d 2000-01-02 foo
   committing files:
   foo
   committing manifest
   committing changelog
   updating the branch cache
   committed changeset 1:45589e459b2edfbf3dbde7e01f611d2c1e7453d7
   result: 0
   running: --debug log -r 0
   changeset:   0:0e46349438790c460c5c9f7546bfcd39b267bbd2
   phase:       draft
   parent:      -1:0000000000000000000000000000000000000000
   parent:      -1:0000000000000000000000000000000000000000
   manifest:    0:9091aa5df980aea60860a2e39c95182e68d1ddec
   user:        test
   date:        Sat Jan 01 00:00:00 2000 +0000
   files+:      foo
   extra:       branch=default
   description:
   commit1
   
   
   result: 0
   running: --debug log -r tip
   changeset:   1:45589e459b2edfbf3dbde7e01f611d2c1e7453d7
   tag:         tip
   phase:       draft
   parent:      0:0e46349438790c460c5c9f7546bfcd39b267bbd2
   parent:      -1:0000000000000000000000000000000000000000
   manifest:    1:895aa9b7886f89dd017a6d62524e1f9180b04df9
   user:        test
   date:        Sun Jan 02 00:00:00 2000 +0000
   files:       foo
   extra:       branch=default
   description:
   commit2
   
   
   result: 0
   $ hg blackbox
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> updating the branch cache
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> updated branch cache (served) in * seconds (glob)
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> wrote branch cache (served) with 1 labels and 1 nodes
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> --debug commit -m commit2 -d 2000-01-02 foo exited 0 after *.?? seconds (glob)
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> --debug log -r 0
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> writing .hg/cache/tags2-visible with 0 tags
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> --debug log -r 0 exited 0 after *.?? seconds (glob)
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> --debug log -r tip
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> --debug log -r tip exited 0 after *.?? seconds (glob)
   1970/01/01 00:00:00 bob @45589e459b2edfbf3dbde7e01f611d2c1e7453d7 (5000)> blackbox
 
+Skip rotation if the .hg is read-only
+
+#if unix-permissions
+  $ chmod -w .hg
+  $ hg log -r. -T '{rev}\n' --config blackbox.maxsize=1 --debug
+  warning: cannot rename '$TESTTMP/blackboxtest3/.hg/blackbox.log.1' to '$TESTTMP/blackboxtest3/.hg/blackbox.log': Permission denied
+  warning: cannot write to blackbox.log: Permission denied
+  1
+  $ chmod +w .hg
+#endif
+
 Test log recursion from dirty status check
 
   $ cat > ../r.py <<EOF
   > from mercurial import context, error, extensions
   > x=[False]
   > def status(orig, *args, **opts):
   >     args[0].repo().ui.log(b"broken", b"recursion?")
   >     return orig(*args, **opts)
   > def reposetup(ui, repo):
   >     extensions.wrapfunction(context.basectx, 'status', status)
   > EOF
   $ hg id --config extensions.x=../r.py --config blackbox.dirty=True
   45589e459b2e tip
 
 cleanup
   $ cd ..
 
 Test missing log directory, which shouldn't be created automatically
 
   $ cat <<'EOF' > closeremove.py
   > def reposetup(ui, repo):
   >     class rmrepo(repo.__class__):
   >         def close(self):
   >             super(rmrepo, self).close()
   >             self.ui.debug(b'removing %s\n' % self.vfs.base)
   >             self.vfs.rmtree()
   >     repo.__class__ = rmrepo
   > EOF
 
   $ hg init gone
   $ cd gone
   $ cat <<'EOF' > .hg/hgrc
   > [extensions]
   > closeremove = ../closeremove.py
   > EOF
   $ hg log --debug
   removing $TESTTMP/gone/.hg
   warning: cannot write to blackbox.log: $ENOENT$ (no-windows !)
   warning: cannot write to blackbox.log: $TESTTMP/gone/.hg/blackbox.log: $ENOTDIR$ (windows !)
   $ cd ..
 
 blackbox should disable itself if track is empty
 
   $ hg --config blackbox.track= init nothing_tracked
   $ cd nothing_tracked
   $ cat >> .hg/hgrc << EOF
   > [blackbox]
   > track =
   > EOF
   $ hg blackbox
   $ cd $TESTTMP
 
 a '*' entry in blackbox.track is interpreted as log everything
 
   $ hg --config blackbox.track='*' \
   >    --config blackbox.logsource=True \
   >    init track_star
   $ cd track_star
   $ cat >> .hg/hgrc << EOF
   > [blackbox]
   > logsource = True
   > track = *
   > EOF
 (only look for entries with specific logged sources, otherwise this test is
 pretty brittle)
   $ hg blackbox | egrep '\[command(finish)?\]'
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000) [commandfinish]> --config *blackbox.track=* --config *blackbox.logsource=True* init track_star exited 0 after * seconds (glob)
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000) [command]> blackbox
   $ cd $TESTTMP
 
 #if chg
 
 when using chg, blackbox.log should get rotated correctly
 
   $ cat > $TESTTMP/noop.py << EOF
   > from __future__ import absolute_import
   > import time
   > from mercurial import registrar, scmutil
   > cmdtable = {}
   > command = registrar.command(cmdtable)
   > @command(b'noop')
   > def noop(ui, repo):
   >     pass
   > EOF
 
   $ hg init blackbox-chg
   $ cd blackbox-chg
 
   $ cat > .hg/hgrc << EOF
   > [blackbox]
   > maxsize = 500B
   > [extensions]
   > # extension change forces chg to restart
   > noop=$TESTTMP/noop.py
   > EOF
 
   $ "$PYTHON" -c 'print("a" * 400)' > .hg/blackbox.log
   $ chg noop
   $ chg noop
   $ chg noop
   $ chg noop
   $ chg noop
 
   $ cat > showsize.py << 'EOF'
   > import os
   > import sys
   > limit = 500
   > for p in sys.argv[1:]:
   >     size = os.stat(p).st_size
   >     if size >= limit:
   >         desc = '>='
   >     else:
   >         desc = '<'
   >     print('%s: %s %d' % (p, desc, limit))
   > EOF
 
   $ "$PYTHON" showsize.py .hg/blackbox*
   .hg/blackbox.log: < 500
   .hg/blackbox.log.1: >= 500
   .hg/blackbox.log.2: >= 500
 
   $ cd ..
 
 With chg, blackbox should not create the log file if the repo is gone
 
   $ hg init repo1
   $ hg --config extensions.a=! -R repo1 log
   $ rm -rf $TESTTMP/repo1
   $ hg --config extensions.a=! init repo1
 
 #endif
 
 blackbox should work if repo.ui.log is not called (issue5518)
 
   $ cat > $TESTTMP/raise.py << EOF
   > from __future__ import absolute_import
   > from mercurial import registrar, scmutil
   > cmdtable = {}
   > command = registrar.command(cmdtable)
   > @command(b'raise')
   > def raisecmd(*args):
   >     raise RuntimeError('raise')
   > EOF
 
   $ cat >> $HGRCPATH << EOF
   > [blackbox]
   > track = commandexception
   > [extensions]
   > raise=$TESTTMP/raise.py
   > EOF
 
   $ hg init $TESTTMP/blackbox-exception-only
   $ cd $TESTTMP/blackbox-exception-only
 
 #if chg
  (chg exits 255 because it fails to receive an exit code)
   $ hg raise 2>/dev/null
   [255]
 #else
  (hg exits 1 because Python default exit code for uncaught exception is 1)
   $ hg raise 2>/dev/null
   [1]
 #endif
 
   $ head -1 .hg/blackbox.log
   1970/01/01 00:00:00 bob @0000000000000000000000000000000000000000 (5000)> ** Unknown exception encountered with possibly-broken third-party extension "mock" (version N/A)
   $ tail -2 .hg/blackbox.log
   RuntimeError: raise