[3.8] bpo-37936: Systematically distinguish rooted vs. unrooted in .gitignore (GH-15823)

.gitignore

@@ -1,11 +1,14 @@
-# Two-trick pony for OSX and other case insensitive file systems:
-# Ignore ./python binary on Unix but still look into ./Python/ directory.
-/python
-!/Python/
+#####
+# First, rules intended to apply in all subdirectories.
+# These contain no slash, or only a trailing slash.
 
 *.cover
 *.iml
 *.o
+*.a
+*.so*
+*.dylib
+*.dll
 *.orig
 *.pyc
 *.pyd
@@ -18,6 +21,31 @@
 *.profraw
 *.dyn
 .gdb_history
+.purify
+__pycache__
+.hg/
+.svn/
+.idea/
+tags
+TAGS
+.vs/
+.vscode/
+gmon.out
+.coverage
+.mypy_cache/
+
+*.exe
+!Lib/distutils/command/*.exe
+
+# Ignore core dumps... but not Tools/msi/core/ or the like.
+core
+!core/
+
+
+#####
+# Then, rules meant for a specific location relative to the repo root.
+# These must contain a non-trailing slash (and may also have a trailing slash.)
+
 Doc/build/
 Doc/venv/
 Doc/.venv/
@@ -29,7 +57,7 @@ Lib/lib2to3/*.pickle
 Lib/test/data/*
 !Lib/test/data/README
 /Makefile
-Makefile.pre
+/Makefile.pre
 Misc/python.pc
 Misc/python-embed.pc
 Misc/python-config.sh
@@ -38,12 +66,9 @@ Modules/Setup.local
 Modules/config.c
 Modules/ld_so_aix
 Programs/_freeze_importlib
-Programs/_freeze_importlib.exe
 Programs/_testembed
-Programs/_testembed.exe
 PC/python_nt*.h
 PC/pythonnt_rc*.h
-PC/*/*.exe
 PC/*/*.exp
 PC/*/*.lib
 PC/*/*.bsc
@@ -62,52 +87,34 @@ PCbuild/*-pgi
 PCbuild/*-pgo
 PCbuild/*.VC.db
 PCbuild/*.VC.opendb
-PCbuild/.vs/
 PCbuild/amd64/
 PCbuild/arm32/
 PCbuild/arm64/
 PCbuild/obj/
 PCbuild/win32/
-.purify
-__pycache__
-autom4te.cache
-build/
-buildno
-config.cache
-config.log
-config.status
-config.status.lineno
-core
-!Tools/msi/core/
-db_home
-.hg/
-.idea/
-ipch/
-libpython*.a
-libpython*.so*
-libpython*.dylib
-libpython*.dll
-platform
-pybuilddir.txt
+/autom4te.cache
+/build/
+/config.cache
+/config.log
+/config.status
+/config.status.lineno
+/platform
+/pybuilddir.txt
 /pyconfig.h
-python-config
-python-config.py
-python.bat
-python.exe
-python-gdb.py
-python.exe-gdb.py
-reflog.txt
-.svn/
-tags
-TAGS
-.coverage
-coverage/
-externals/
-htmlcov/
+/python-config
+/python-config.py
+/python.bat
+/python-gdb.py
+/python.exe-gdb.py
+/reflog.txt
+/coverage/
+/externals/
+/htmlcov/
 Tools/msi/obj
 Tools/ssl/amd64
 Tools/ssl/win32
-.vs/
-.vscode/
-gmon.out
-.mypy_cache/
+
+# Two-trick pony for OSX and other case insensitive file systems:
+# Ignore ./python binary on Unix but still look into ./Python/ directory.
+/python
+!/Python/

Lib/test/libregrtest/runtest.py

@@ -313,9 +313,7 @@ def cleanup_test_droppings(test_name, verbose):
     # since if a test leaves a file open, it cannot be deleted by name (while
     # there's nothing we can do about that here either, we can display the
     # name of the offending test, which is a real help).
-    for name in (support.TESTFN,
-                 "db_home",
-                ):
+    for name in (support.TESTFN,):
         if not os.path.exists(name):
             continue
 

Misc/NEWS.d/next/Build/2019-09-10-00-54-48.bpo-37936.E7XEwu.rst

@@ -0,0 +1,5 @@
+The :file:`.gitignore` file systematically keeps "rooted", with a
+non-trailing slash, all the rules that are meant to apply to files in a
+specific place in the repo.  Previously, when the intended file to ignore
+happened to be at the root of the repo, we'd most often accidentally also
+ignore files and directories with the same name anywhere in the tree.