Add support for flake8 per-file-ignores

Author: brandonwillard

Diff for: pylsp/config/flake8_conf.py

@@ -28,6 +28,7 @@
     ('ignore', 'plugins.flake8.ignore', list),
     ('max-line-length', 'plugins.flake8.maxLineLength', int),
     ('select', 'plugins.flake8.select', list),
+    ('per-file-ignores', 'plugins.flake8.perFileIgnores', list),
 ]
 
 

Diff for: pylsp/config/source.py

@@ -69,6 +69,8 @@ def _get_opt(config, key, option, opt_type):
 
 
 def _parse_list_opt(string):
+    if string.startswith("\n"):
+        return [s.strip().rstrip(",") for s in string.split("\n") if s.strip()]
     return [s.strip() for s in string.split(",") if s.strip()]
 
 

Diff for: pylsp/plugins/flake8_lint.py

@@ -5,7 +5,9 @@
 import logging
 import os.path
 import re
-from subprocess import Popen, PIPE
+from pathlib import PurePath
+from subprocess import PIPE, Popen
+
 from pylsp import hookimpl, lsp
 
 log = logging.getLogger(__name__)
@@ -24,12 +26,21 @@ def pylsp_lint(workspace, document):
     settings = config.plugin_settings('flake8', document_path=document.path)
     log.debug("Got flake8 settings: %s", settings)
 
+    ignores = settings.get("ignore", [])
+    per_file_ignores = settings.get("perFileIgnores")
+
+    if per_file_ignores:
+        for path in per_file_ignores:
+            file_pat, errors = path.split(":")
+            if PurePath(document.path).match(file_pat):
+                ignores.extend(errors.split(","))
+
     opts = {
         'config': settings.get('config'),
         'exclude': settings.get('exclude'),
         'filename': settings.get('filename'),
         'hang-closing': settings.get('hangClosing'),
-        'ignore': settings.get('ignore'),
+        'ignore': ignores or None,
         'max-line-length': settings.get('maxLineLength'),
         'select': settings.get('select'),
     }

Diff for: test/plugins/test_flake8_lint.py

@@ -85,3 +85,77 @@ def test_flake8_executable_param(workspace):
 
         (call_args,) = popen_mock.call_args[0]
         assert flake8_executable in call_args
+
+
+def get_flake8_cfg_settings(workspace, config_str):
+    """Write a ``setup.cfg``, load it in the workspace, and return the flake8 settings.
+
+    This function creates a ``setup.cfg``; you'll have to delete it yourself.
+    """
+
+    with open(os.path.join(workspace.root_path, "setup.cfg"), "w+") as f:
+        f.write(config_str)
+
+    workspace.update_config({"pylsp": {"configurationSources": ["flake8"]}})
+
+    return workspace._config.plugin_settings("flake8")
+
+
+def test_flake8_multiline(workspace):
+    config_str = r"""[flake8]
+exclude =
+    blah/,
+    file_2.py
+    """
+
+    doc_str = "print('hi')\nimport os\n"
+
+    doc_uri = uris.from_fs_path(os.path.join(workspace.root_path, "blah/__init__.py"))
+    workspace.put_document(doc_uri, doc_str)
+
+    flake8_settings = get_flake8_cfg_settings(workspace, config_str)
+
+    assert "exclude" in flake8_settings
+    assert len(flake8_settings["exclude"]) == 2
+
+    with patch('pylsp.plugins.flake8_lint.Popen') as popen_mock:
+        mock_instance = popen_mock.return_value
+        mock_instance.communicate.return_value = [bytes(), bytes()]
+
+        doc = workspace.get_document(doc_uri)
+        flake8_lint.pylsp_lint(workspace, doc)
+
+    call_args = popen_mock.call_args[0][0]
+    assert call_args == ["flake8", "-", "--exclude=blah/,file_2.py"]
+
+    os.unlink(os.path.join(workspace.root_path, "setup.cfg"))
+
+
+def test_flake8_per_file_ignores(workspace):
+    config_str = r"""[flake8]
+ignores = F403
+per-file-ignores =
+    **/__init__.py:F401,E402
+    test_something.py:E402,
+exclude =
+    file_1.py
+    file_2.py
+    """
+
+    doc_str = "print('hi')\nimport os\n"
+
+    doc_uri = uris.from_fs_path(os.path.join(workspace.root_path, "blah/__init__.py"))
+    workspace.put_document(doc_uri, doc_str)
+
+    flake8_settings = get_flake8_cfg_settings(workspace, config_str)
+
+    assert "perFileIgnores" in flake8_settings
+    assert len(flake8_settings["perFileIgnores"]) == 2
+    assert "exclude" in flake8_settings
+    assert len(flake8_settings["exclude"]) == 2
+
+    doc = workspace.get_document(doc_uri)
+    res = flake8_lint.pylsp_lint(workspace, doc)
+    assert not res
+
+    os.unlink(os.path.join(workspace.root_path, "setup.cfg"))