| .. Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0 |
| .. For details: https://bitbucket.org/ned/coveragepy/src/default/NOTICE.txt |
| |
| .. _trouble: |
| |
| ========================= |
| Things that cause trouble |
| ========================= |
| |
| .. :history: 20121231T085200, brand new docs. |
| .. :history: 20150124T160800, remove obsolete stuff. |
| |
| |
| Coverage.py works well, and I want it to properly measure any Python program, |
| but there are some situations it can't cope with. This page details some known |
| problems, with possible courses of action, and links to coverage.py bug reports |
| with more information. |
| |
| I would love to :ref:`hear from you <contact>` if you have information about |
| any of these problems, even just to explain to me why you want them to start |
| working properly. |
| |
| If your problem isn't discussed here, you can of course search the `coverage.py |
| bug tracker`_ directly to see if there is some mention of it. |
| |
| .. _coverage.py bug tracker: https://bitbucket.org/ned/coveragepy/issues?status=new&status=open |
| |
| |
| Things that don't work |
| ---------------------- |
| |
| There are a number of popular modules, packages, and libraries that prevent |
| coverage.py from working properly: |
| |
| * `execv`_, or one of its variants. These end the current program and replace |
| it with a new one. This doesn't save the collected coverage data, so your |
| program that calls execv will not be fully measured. A patch for coverage.py |
| is in `issue 43`_. |
| |
| * `thread`_, in the Python standard library, is the low-level threading |
| interface. Threads created with this module will not be traced. Use the |
| higher-level `threading`_ module instead. |
| |
| * `sys.settrace`_ is the Python feature that coverage.py uses to see what's |
| happening in your program. If another part of your program is using |
| sys.settrace, then it will conflict with coverage.py, and it won't be |
| measured properly. |
| |
| .. _execv: http://docs.python.org/library/os#os.execl |
| .. _sys.settrace: http://docs.python.org/library/sys.html#sys.settrace |
| .. _thread: https://docs.python.org/2/library/thread.html |
| .. _threading: http://docs.python.org/library/threading.html |
| .. _issue 43: https://bitbucket.org/ned/coveragepy/issue/43/coverage-measurement-fails-on-code |
| |
| |
| Things that require --timid |
| --------------------------- |
| |
| Some packages interfere with coverage measurement, but you might be able to |
| make it work by using the ``--timid`` command-line switch, or the ``[run] |
| timid=True`` configuration option. |
| |
| * `DecoratorTools`_, or any package which uses it, notably `TurboGears`_. |
| DecoratorTools fiddles with the trace function. You will need to use |
| ``--timid``. |
| |
| .. _DecoratorTools: http://pypi.python.org/pypi/DecoratorTools |
| .. _TurboGears: http://turbogears.org/ |
| |
| |
| Still having trouble? |
| --------------------- |
| |
| If your problem isn't mentioned here, and isn't already reported in the |
| `coverage.py bug tracker`_, please :ref:`get in touch with me <contact>`, |
| we'll figure out a solution. |