test-gpg: make temporary copy of GNUPGHOME GnuPG v2 will convert v1 secret keys and create a socket under $GNUPGHOME. This patch makes sure no state would persist. We no longer need to verify trustdb.gpg, which was added by aae219a99a6e.

hgweb: document why we don't allow untrusted settings to control zlib Added comment per discussion on mercurial-devel.

hgweb: profile HTTP requests Currently, running `hg serve --profile` doesn't yield anything useful: when the process is terminated the profiling output displays results from the main thread, which typically spends most of its time in select.select(). Furthermore, it has no meaningful results from mercurial.* modules because the threads serving HTTP requests don't actually get profiled. This patch teaches the hgweb wsgi applications to profile individual requests. If profiling is enabled, the profiler kicks in after HTTP/WSGI environment processing but before Mercurial's main request processing. The profile results are printed to the configured profiling output. If running `hg serve` from a shell, they will be printed to stderr, just before the HTTP request line is logged. If profiling to a file, we only write a single profile to the file because the file is not opened in append mode. We could add support for appending to files in a future patch if someone wants it. Per request profiling doesn't work with the statprof profiler because internally that profiler collects samples from the thread that *initially* requested profiling be enabled. I have plans to address this by vendoring Facebook's customized statprof and then improving it.

hgweb: abstract call to hgwebdir wsgi function The function names and behavior now matches hgweb. The reason for this will be obvious in the next patch.

profiling: don't error with statprof when profiling has already started statprof.reset() asserts if profiling has already started. So don't call if it profiling is already running.

profiling: add a context manager that no-ops if profiling isn't enabled And refactor dispatch.py to use it. As you can see, the resulting code is much simpler. I was tempted to inline _runcommand as part of writing this series. However, a number of extensions wrap _runcommand. So keeping it around is necessary (extensions can't easily wrap runcommand because it calls hooks before and after command execution).

profiling: make profiling functions context managers (API) This makes profiling more flexible since we can now call multiple functions when a profiler is active. But the real reason for this is to enable a future consumer to profile a function that returns a generator. We can't do this from the profiling function itself because functions can either be generators or have return values: they can't be both. So therefore it isn't possible to have a generic profiling function that can both consume and re-emit a generator and return a value.

dispatch: set profiling.enabled when profiling is enabled We do this for other global command arguments. We don't for --profile for reasons that are unknown to me. Probably because nobody has needed it. An upcoming patch will introduce a new consumer of the profiling code. It doesn't have access to command line arguments. So let's set the config option during argument processing. We also remove a check for "options['profile']" because it is now redundant.

profiling: move profiling code from dispatch.py (API) Currently, profiling code lives in dispatch.py, which is a low-level module centered around command dispatch. Furthermore, dispatch.py imports a lot of other modules, meaning that importing dispatch.py to get at profiling functionality would often result in a module import cycle. Profiling is a generic activity. It shouldn't be limited to command dispatch. This patch moves profiling code from dispatch.py to the new profiling.py. The low-level "run a profiler against a function" functions have been moved verbatim. The code for determining how to invoke the profiler has been extracted to its own function. I decided to create a new module rather than stick this code elsewhere (such as util.py) because util.py is already quite large. And, I foresee this file growing larger once Facebook's profiling enhancements get added to it.

merge with stable