Relax installable dir check to allow cfg-only

src/pip/_internal/utils/misc.py

@@ -269,18 +269,15 @@ def tabulate(rows):
  return table, sizes
 
 
-def is_installable_dir(path):
- # type: (str) -> bool
- """Is path is a directory containing setup.py or pyproject.toml?"""
+def is_installable_dir(path: str) -> bool:
+ """Is path is a directory containing pyproject.toml, setup.cfg or setup.py?
+ """
  if not os.path.isdir(path):
  return False
- setup_py = os.path.join(path, "setup.py")
- if os.path.isfile(setup_py):
- return True
- pyproject_toml = os.path.join(path, "pyproject.toml")
- if os.path.isfile(pyproject_toml):
- return True
- return False
+ return any(
+ os.path.isfile(os.path.join(path, signifier))
+ for signifier in ("pyproject.toml", "setup.cfg", "setup.py")
+ )
 
 
 def read_chunks(file, size=io.DEFAULT_BUFFER_SIZE):