Add option to list config files with pip config

news/6741.feature

@@ -0,0 +1 @@
+Add a subcommand ``list-files`` to ``pip config`` to list available configuration files and their location

src/pip/_internal/commands/configuration.py

@@ -13,6 +13,7 @@
     kinds,
 )
 from pip._internal.exceptions import PipError
+from pip._internal.utils.logging import indent_log
 from pip._internal.utils.misc import get_prog, write_output
 
 logger = logging.getLogger(__name__)
@@ -28,6 +29,7 @@ class ConfigurationCommand(Command):
         get: Get the value associated with name
         set: Set the name=value
         unset: Unset the value associated with name
+        list-files: List the configuration files
 
     If none of --user, --global and --site are passed, a virtual
     environment configuration file is used if one is active and the file
@@ -43,6 +45,7 @@ class ConfigurationCommand(Command):
         %prog [<file-option>] get name
         %prog [<file-option>] set name value
         %prog [<file-option>] unset name
+        %prog [<file-option>] list-files
     """
 
     def __init__(self, *args, **kwargs):
@@ -93,7 +96,8 @@ def run(self, options, args):
             "edit": self.open_in_editor,
             "get": self.get_name,
             "set": self.set_name_value,
-            "unset": self.unset_name
+            "unset": self.unset_name,
+            "list-files": self.list_config_files
         }
 
         # Determine action
@@ -180,6 +184,16 @@ def unset_name(self, options, args):
 
         self._save_configuration()
 
+    def list_config_files(self, options, args):
+        self._get_n_args(args, "list-files", n=0)
+
+        for variant, files in sorted(self.configuration.iter_config_files()):
+            write_output("%s:", variant)
+            for fname in files:
+                with indent_log():
+                    write_output("%s, exists: %r ",
+                                 fname, os.path.exists(fname))
+
     def open_in_editor(self, options, args):
         editor = self._determine_editor(options)
 

src/pip/_internal/configuration.py

@@ -280,7 +280,7 @@ def _load_config_files(self):
         # type: () -> None
         """Loads configuration from configuration files
         """
-        config_files = dict(self._iter_config_files())
+        config_files = dict(self.iter_config_files())
         if config_files[kinds.ENV][0:1] == [os.devnull]:
             logger.debug(
                 "Skipping loading configuration files due to "
@@ -370,7 +370,7 @@ def _get_environ_vars(self):
                 yield key[4:].lower(), val
 
     # XXX: This is patched in the tests.
-    def _iter_config_files(self):
+    def iter_config_files(self):
         # type: () -> Iterable[Tuple[Kind, List[str]]]
         """Yields variant and configuration files associated with it.
 

tests/unit/test_options.py

@@ -393,7 +393,7 @@ def test_venv_config_file_found(self, monkeypatch):
         cp = pip._internal.configuration.Configuration(isolated=False)
 
         files = []
-        for _, val in cp._iter_config_files():
+        for _, val in cp.iter_config_files():
             files.extend(val)
 
         assert len(files) == 4