Enable keeping test-created temp dirs

1 files changed, 8 insertions, 3 deletions

diff --git a/doc/contributing.rst b/doc/contributing.rst
index 71fa6937..24a2636d 100644
--- a/doc/contributing.rst
+++ b/doc/contributing.rst
@@ -122,13 +122,14 @@ To limit tox to just a few versions of Python, use the ``-e`` switch::
 To run just a few tests, you can use `pytest test selectors`_::
 
     $ tox tests/test_misc.py
-    $ tox tests/test_misc.py::SetupPyTest
-    $ tox tests/test_misc.py::SetupPyTest::test_metadata
+    $ tox tests/test_misc.py::HasherTest
+    $ tox tests/test_misc.py::HasherTest::test_string_hashing
 
 These command run the tests in one file, one class, and just one test,
 respectively.
 
-You can also affect the test runs with environment variables:
+You can also affect the test runs with environment variables. Define any of
+these as 1 to use them:
 
 - COVERAGE_NO_PYTRACER disables the Python tracer if you only want to run the
   CTracer tests.
@@ -142,6 +143,10 @@ You can also affect the test runs with environment variables:
 - COVERAGE_KEEP_OUTPUT will save the output files that were generated by the
   gold-file tests, ones that compare output files to saved gold files.
 
+- COVERAGE_KEEP_TMP keeps the temporary directories in which tests are run.
+  This makes debugging tests easier. The temporary directories are at
+  ``$TMPDIR/coverage_test/*``, and are named for the test that made them.
+
 
 Of course, run all the tests on every version of Python you have, before
 submitting a change.