[PYLINT-HOME change] Less spam when using pylint in parallel

The spam prevention is due to pylint being used in parallel by
pre-commit, and the message being spammy in this context
Also if you work with old version of pylint that recreate the
old pylint home, you can get the old message for a long time.

Author: Pierre-Sassoulas

pylint/config/__init__.py

@@ -35,6 +35,7 @@
 import os
 import pickle
 import sys
+from datetime import datetime
 
 import appdirs
 
@@ -66,14 +67,32 @@
     PYLINT_HOME = ".pylint.d"
 else:
     PYLINT_HOME = appdirs.user_cache_dir("pylint")
-
+    # The spam prevention is due to pylint being used in parallel by
+    # pre-commit, and the message being spammy in this context
+    # Also if you work with old version of pylint that recreate the
+    # old pylint home, you can get the old message for a long time.
+    prefix_spam_prevention = "pylint_warned_about_old_cache_already"
+    spam_prevention_file = os.path.join(
+        PYLINT_HOME,
+        datetime.now().strftime(prefix_spam_prevention + "_%Y-%m-%d.temp"),
+    )
     old_home = os.path.join(USER_HOME, ".pylint.d")
-    if os.path.exists(old_home):
+    if os.path.exists(old_home) and not os.path.exists(spam_prevention_file):
         print(
             f"PYLINTHOME is now '{PYLINT_HOME}' but obsolescent '{old_home}' is found; "
             "you can safely remove the latter",
             file=sys.stderr,
         )
+        # Remove old spam prevention file
+        for filename in os.listdir(PYLINT_HOME):
+            if prefix_spam_prevention in filename:
+                try:
+                    os.remove(os.path.join(PYLINT_HOME, filename))
+                except OSError:
+                    pass
+        # Create spam prevention file for today
+        with open(spam_prevention_file, "w", encoding="utf8") as f:
+            f.write("")
 
 
 def _get_pdata_path(base_name, recurs):