Rehabilitate autotest.py.
In README: Write up (Guido's) rules for intra-test imports; warn against
asserts; document test_support.use_large_resources.
diff --git a/Lib/test/README b/Lib/test/README
index ae39d27..81e11fa 100644
--- a/Lib/test/README
+++ b/Lib/test/README
@@ -136,6 +136,16 @@
completion print) to indicate the failure, but proceed instead of
raising TestFailed.
+ * Use "assert" sparingly, if at all. It's usually better to just print
+ what you got, and rely on regrtest's got-vs-expected comparison to
+ catch deviations from what you expect. assert statements aren't
+ executed at all when regrtest is run in -O mode; and, because they
+ cause the test to stop immediately, can lead to a long & tedious
+ test-fix, test-fix, test-fix, ... cycle when things are badly broken
+ (and note that "badly broken" often includes running the test suite
+ for the first time on new platforms or under new implementations of
+ the language).
+
Miscellaneous
@@ -157,10 +167,36 @@
modules use it. Search for "verbose" in the test_*.py files to see
lots of examples.
+ * use_large_resources - true iff tests requiring large time or space
+ should be run.
+
* fcmp(x,y) - you can call this function to compare two floating point
numbers when you expect them to only be approximately equal withing a
fuzz factor (test_support.FUZZ, which defaults to 1e-6).
+NOTE: Always import something from test_support like so:
+
+ from test_support import verbose
+
+or like so:
+
+ import test_support
+ ... use test_support.verbose in the code ...
+
+Never import anything from test_support like this:
+
+ from test.test_support import verbose
+
+"test" is a package already, so can refer to modules it contains without
+"test." qualification. If you do an explicit "test.xxx" qualification, that
+can fool Python into believing test.xxx is a module distinct from the xxx
+in the current package, and you can end up importing two distinct copies of
+xxx. This is especially bad if xxx=test_support, as regrtest.py can (and
+routinely does) overwrite its "verbose" and "use_large_resources"
+attributes: if you get a second copy of test_support loaded, it may not
+have the same values for those as regrtest intended.
+
+
Python and C statement coverage results are currently available at
http://www.musi-cal.com/~skip/python/Python/dist/src/