Ignore pytest cache

changelog/3286.bugfix.rst

@@ -0,0 +1 @@
+``.pytest_cache`` directory is now automatically ignored by Git. Users who would like to contribute a solution for other SCMs please consult/comment on this issue.

src/_pytest/cacheprovider.py

@@ -115,15 +115,18 @@ def set(self, key, value):
         else:
             with f:
                 json.dump(value, f, indent=2, sort_keys=True)
-                self._ensure_readme()
-
-    def _ensure_readme(self):
+                self._ensure_supporting_files()
 
+    def _ensure_supporting_files(self):
+        """Create supporting files in the cache dir that are not really part of the cache."""
         if self._cachedir.is_dir():
             readme_path = self._cachedir / "README.md"
             if not readme_path.is_file():
                 readme_path.write_text(README_CONTENT)
 
+            msg = u"# created by pytest automatically, do not change\n*"
+            self._cachedir.joinpath(".gitignore").write_text(msg, encoding="UTF-8")
+
 
 class LFPlugin(object):
     """ Plugin which implements the --lf (run last-failing) option """

testing/python/fixture.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+import sys
 import textwrap
 
 import pytest
@@ -488,6 +489,10 @@ def test_method(self, something):
         assert len(arg2fixturedefs) == 1
         assert arg2fixturedefs["something"][0].argname == "something"
 
+    @pytest.mark.skipif(
+        hasattr(sys, "pypy_version_info"),
+        reason="this method of test doesn't work on pypy",
+    )
     def test_request_garbage(self, testdir):
         testdir.makepyfile(
             """
@@ -498,33 +503,32 @@ def test_request_garbage(self, testdir):
 
             @pytest.fixture(autouse=True)
             def something(request):
-                # this method of test doesn't work on pypy
-                if hasattr(sys, "pypy_version_info"):
-                    yield
-                else:
-                    original = gc.get_debug()
-                    gc.set_debug(gc.DEBUG_SAVEALL)
-                    gc.collect()
+                original = gc.get_debug()
+                gc.set_debug(gc.DEBUG_SAVEALL)
+                gc.collect()
 
-                    yield
+                yield
 
+                try:
                     gc.collect()
                     leaked_types = sum(1 for _ in gc.garbage
                                        if isinstance(_, PseudoFixtureDef))
 
+                    # debug leaked types if the test fails
+                    print(leaked_types)
+
                     gc.garbage[:] = []
 
-                    try:
-                        assert leaked_types == 0
-                    finally:
-                        gc.set_debug(original)
+                    assert leaked_types == 0
+                finally:
+                    gc.set_debug(original)
 
             def test_func():
                 pass
         """
         )
-        reprec = testdir.inline_run()
-        reprec.assertoutcome(passed=1)
+        result = testdir.runpytest()
+        result.stdout.fnmatch_lines("* 1 passed in *")
 
     def test_getfixturevalue_recursive(self, testdir):
         testdir.makeconftest(

testing/test_cacheprovider.py

@@ -884,3 +884,14 @@ def test_always_passes():
         )
         testdir.runpytest()
         assert self.check_readme(testdir) is True
+
+
+def test_gitignore(testdir):
+    """Ensure we automatically create .gitignore file in the pytest_cache directory (#3286)."""
+    from _pytest.cacheprovider import Cache
+
+    config = testdir.parseconfig()
+    cache = Cache.for_config(config)
+    cache.set("foo", "bar")
+    msg = "# created by pytest automatically, do not change\n*"
+    assert cache._cachedir.joinpath(".gitignore").read_text(encoding="UTF-8") == msg