Created 24 May 2009, last updated 6 March 2010

These are the major changes for coverage.py. For a more complete change history, see the CHANGES.txt file in the source tree.

Version 3.3.1, 6 March 2010

Using parallel=True in a .coveragerc file prevented reporting, but now does not, fixing issue 49.
When running your code with coverage run, if you call sys.exit(), coverage.py will exit with that status code, fixing issue 50.

Version 3.3, 24 February 2010

Settings are now read from a .coveragerc file. A specific file can be specified on the command line with --rcfile=FILE. The name of the file can be programmatically set with the config_file argument to the coverage() constructor, or reading a config file can be disabled with config_file=False.
Added coverage.process_start to enable coverage measurement when Python starts.
Parallel data file names now have a random number appended to them in addition to the machine name and process id. Also, parallel data files combined with coverage combine are deleted after they’re combined, to clean up unneeded files. Fixes issue 40.
Exceptions thrown from product code run with coverage run are now displayed without internal coverage.py frames, so the output is the same as when the code is run without coverage.py.
Fixed issue 39 and issue 47.

Branch coverage: coverage.py can tell you which branches didn’t have both (or all) choices executed, even where the choice doesn’t affect which lines were executed. See Branch Coverage for more details.
The table of contents in the HTML report is now sortable: click the headers on any column. The sorting is persisted so that subsequent reports are sorted as you wish. Thanks, Chris Adams.
XML reporting has file paths that let Cobertura find the source code, fixing issue 21.
The --omit option now works much better than before, fixing issue 14 and issue 33. Thanks, Danek Duvall.
Added a --version option on the command line.
Program execution under coverage is a few percent faster.
Some exceptions reported by the command line interface have been cleaned up so that tracebacks inside coverage.py aren’t shown. Fixes issue 23.
Fixed some problems syntax coloring sources with line continuations and source with tabs: issue 30 and issue 31.

Python 3.1 is now supported.
Coverage.py has a new command line syntax with sub-commands. This expands the possibilities for adding features and options in the future. The old syntax is still supported. Try coverage help to see the new commands. Thanks to Ben Finney for early help.
Added an experimental coverage xml command for producing coverage reports in a Cobertura-compatible XML format. Thanks, Bill Hart.
Added the --timid option to enable a simpler slower trace function that works for DecoratorTools projects, including TurboGears. Fixed issue 12 and issue 13.
HTML reports now display syntax-colored Python source.
Added a coverage debug command for getting diagnostic information about the coverage.py installation.
Source code can now be read from eggs. Thanks, Ross Lawley. Fixes issue 25.

Removed the recursion limit in the tracer function. Previously, code that ran more than 500 frames deep would crash.
Fixed a bizarre problem involving pyexpat, whereby lines following XML parser invocations could be overlooked.
On Python 2.3, coverage.py could mis-measure code with exceptions being raised. This is now fixed.
The coverage.py code itself will now not be measured by coverage.py, and no coverage modules will be mentioned in the nose --with-cover plugin.
When running source files, coverage.py now opens them in universal newline mode just like Python does. This lets it run Windows files on Mac, for example.

Coverage is now a package rather than a module. Functionality has been split into classes.
HTML reports and annotation of source files: use the new -b (browser) switch. Thanks to George Song for code, inspiration and guidance.
The trace function is implemented in C for speed. Coverage runs are now much faster. Thanks to David Christian for productive micro-sprints and other encouragement.
The minimum supported Python version is 2.3.
When using the object api (that is, constructing a coverage() object), data is no longer saved automatically on process exit. You can re-enable it with the auto_data=True parameter on the coverage() constructor. The module-level interface still uses automatic saving.
Code in the Python standard library is not measured by default. If you need to measure standard library code, use the -L command-line switch during execution, or the cover_pylib=True argument to the coverage() constructor.
API changes:
- Added parameters to coverage.__init__ for options that had been set on the coverage object itself.
- Added clear_exclude() and get_exclude_list() methods for programmatic manipulation of the exclude regexes.
- Added coverage.load() to read previously-saved data from the data file.
- coverage.annotate_file is no longer available.
- Removed the undocumented cache_file argument to coverage.usecache().