Create new config option 'config_names'

This configuration option allows us to specify additional configuration
file names under which the mypy config could be found.

Author: hetmankp

README.rst

@@ -36,6 +36,8 @@ Configuration
 ``overrides`` (default is ``[True]``) specifies a list of alternate or supplemental command-line options.
     This modifies the options passed to ``mypy`` or the mypy-specific ones passed to ``dmypy run``. When present, the special boolean member ``True`` is replaced with the command-line options that would've been passed had ``overrides`` not been specified. Later options take precedence, which allows for replacing or negating individual default options (see ``mypy.main:process_options`` and ``mypy --help | grep inverse``).
 
+``config_names`` (default is ``[]``) specifies alternate file names under which the mypy configuration may be found.
+
 This project supports the use of ``pyproject.toml`` for configuration. It is in fact the preferred way. Using that your configuration could look like this:
 
 ::
@@ -76,6 +78,15 @@ With ``overrides`` specified (for example to tell mypy to use a different python
         "overrides": ["--python-executable", "/home/me/bin/python", True]
     }
 
+With ``config_names`` your config could look like this:
+
+::
+
+    {
+        "enabled": True,
+        "config_files": [".config/mypy.ini"]
+    }
+
 
 Developing
 -------------

pylsp_mypy/plugin.py

@@ -119,6 +119,28 @@ def apply_overrides(args: List[str], overrides: List[Any]) -> List[str]:
     return overrides[: -(len(rest) + 1)] + args + rest
 
 
+_mypy_config_names_cache: Dict[str, List[str]] = {}
+
+
+def updateMypyConfigFileMap(config: Config, settings: Any) -> None:
+    """
+    Updates the mypyConfigFileMap for new work spaces or when the
+    'config_names' setting for an existing workspace changes.
+    """
+    workspace = config._root_path
+    config_names = settings.get("config_names", [])
+    if (
+        workspace not in mypyConfigFileMap
+        or _mypy_config_names_cache.get(workspace, []) != config_names
+    ):
+        mypyConfigFile = findConfigFile(
+            workspace, config_names + ["mypy.ini", ".mypy.ini", "pyproject.toml"]
+        )
+        mypyConfigFileMap[workspace] = mypyConfigFile
+
+        log.info("mypyConfigFile = %s", mypyConfigFile)
+
+
 @hookimpl
 def pylsp_lint(
     config: Config, workspace: Workspace, document: Document, is_saved: bool
@@ -166,6 +188,8 @@ def pylsp_lint(
         is_saved,
     )
 
+    updateMypyConfigFileMap(config, settings)
+
     live_mode = settings.get("live_mode", True)
     dmypy = settings.get("dmypy", False)
 
@@ -361,10 +385,7 @@ def init(workspace: str) -> Dict[str, str]:
             with open(path) as file:
                 configuration = ast.literal_eval(file.read())
 
-    mypyConfigFile = findConfigFile(workspace, ["mypy.ini", ".mypy.ini", "pyproject.toml"])
-    mypyConfigFileMap[workspace] = mypyConfigFile
-
-    log.info("mypyConfigFile = %s configuration = %s", mypyConfigFile, configuration)
+    log.info("configuration = %s", configuration)
     return configuration
 
 

test/test_plugin.py

@@ -222,3 +222,34 @@ def test_option_overrides_dmypy(last_diagnostics_monkeypatch, workspace):
         document.path,
     ]
     m.assert_called_with(expected, stderr=-1, stdout=-1, **windows_flag)
+
+
+def test_config_names(tmpdir, last_diagnostics_monkeypatch):
+    DOC_SOURCE = """
+def foo():
+    return
+    unreachable = 1
+"""
+    DOC_ERR_MSG = "Statement is unreachable"
+
+    config_names = [".config/mypy.ini"]
+
+    # Initialize workspace.
+    ws = Workspace(uris.from_fs_path(str(tmpdir)), Mock())
+    ws._config = Config(ws.root_uri, {}, 0, {})
+
+    # Create configuration file for workspace.
+    config_dir = tmpdir.mkdir(".config")
+    mypy_config = config_dir.join("mypy.ini")
+    mypy_config.write("[mypy]\nwarn_unreachable = True\ncheck_untyped_defs = True")
+
+    # Update settings for workspace.
+    plugin.pylsp_settings(ws._config)
+    ws.update_config({"pylsp": {"plugins": {"pylsp_mypy": {"config_names": config_names}}}})
+
+    # Test document to make sure it uses .config/mypy.ini configuration.
+    doc = Document(DOC_URI, ws, DOC_SOURCE)
+    diags = plugin.pylsp_lint(ws._config, ws, doc, is_saved=False)
+    assert len(diags) == 1
+    diag = diags[0]
+    assert diag["message"] == DOC_ERR_MSG