From a5c17c1a19bd0478a8e7543d13cce8fdd30488f2 Mon Sep 17 00:00:00 2001
From: "Eric N. Vander Weele" <ericvw@gmail.com>
Date: Tue, 7 Jan 2020 12:39:21 -0500
Subject: [PATCH 1/3] config: Add 'ignore_config_files' parameter to
 ConfigFileFinder

The `--isolated` flag is passed into `MergedConfigParser.parse()` and
the module-level function `config.get_local_plugins()`.  Since both of
these places utilize the `ConfigFileFinder` object and isolation
pertains to how the `ConfigFileFinder` should behave with respect to
isolation, this incremental change more directly associates the
`ConfigFileFinder` and configuration file isolate.
---
 src/flake8/main/application.py        |  4 +++-
 src/flake8/options/config.py          | 11 +++++++++--
 tests/unit/test_config_file_finder.py | 20 ++++++++++++++++++++
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/flake8/main/application.py b/src/flake8/main/application.py
index 791d5af..7ea3fbb 100644
--- a/src/flake8/main/application.py
+++ b/src/flake8/main/application.py
@@ -335,7 +335,9 @@ class Application(object):
         prelim_opts, remaining_args = self.parse_preliminary_options(argv)
         flake8.configure_logging(prelim_opts.verbose, prelim_opts.output_file)
         config_finder = config.ConfigFileFinder(
-            self.program, prelim_opts.append_config
+            self.program,
+            prelim_opts.append_config,
+            ignore_config_files=prelim_opts.isolated,
         )
         self.find_plugins(
             config_finder, prelim_opts.config, prelim_opts.isolated
diff --git a/src/flake8/options/config.py b/src/flake8/options/config.py
index e1952be..e921f6e 100644
--- a/src/flake8/options/config.py
+++ b/src/flake8/options/config.py
@@ -16,19 +16,26 @@ __all__ = ("ConfigFileFinder", "MergedConfigParser")
 class ConfigFileFinder(object):
     """Encapsulate the logic for finding and reading config files."""
 
-    def __init__(self, program_name, extra_config_files):
-        # type: (str, List[str]) -> None
+    def __init__(
+        self, program_name, extra_config_files, ignore_config_files=False
+    ):
+        # type: (str, List[str], bool) -> None
         """Initialize object to find config files.
 
         :param str program_name:
             Name of the current program (e.g., flake8).
         :param list extra_config_files:
             Extra configuration files specified by the user to read.
+        :param bool ignore_config_files:
+            Determine whether to ignore configuration files or not.
         """
         # The values of --append-config from the CLI
         extra_config_files = extra_config_files or []
         self.extra_config_files = utils.normalize_paths(extra_config_files)
 
+        # The value of --isolated from the CLI.
+        self.ignore_config_files = ignore_config_files
+
         # Platform specific settings
         self.is_windows = sys.platform == "win32"
         self.xdg_home = os.environ.get(
diff --git a/tests/unit/test_config_file_finder.py b/tests/unit/test_config_file_finder.py
index b562c4a..44da8d4 100644
--- a/tests/unit/test_config_file_finder.py
+++ b/tests/unit/test_config_file_finder.py
@@ -124,3 +124,23 @@ def test_read_config_catches_decoding_errors(tmpdir):
     setup_cfg.write_binary(b'[x]\ny = \x81\x8d\x90\x9d')
     _, parsed = config.ConfigFileFinder._read_config(setup_cfg.strpath)
     assert parsed == []
+
+
+def test_ignore_config_files_default_value():
+    """Verify the default 'ignore_config_files' attribute value."""
+    finder = config.ConfigFileFinder('flake8', [])
+    assert finder.ignore_config_files is False
+
+
+@pytest.mark.parametrize('ignore_config_files_arg', [
+    False,
+    True,
+])
+def test_setting_ignore_config_files_value(ignore_config_files_arg):
+    """Verify the 'ignore_config_files' attribute matches constructed value."""
+    finder = config.ConfigFileFinder(
+        'flake8',
+        [],
+        ignore_config_files=ignore_config_files_arg
+    )
+    assert finder.ignore_config_files is ignore_config_files_arg

From 3d546d448a22b131f42444657f0985b37b252097 Mon Sep 17 00:00:00 2001
From: "Eric N. Vander Weele" <ericvw@gmail.com>
Date: Tue, 7 Jan 2020 13:03:34 -0500
Subject: [PATCH 2/3] config: Switch code paths to use
 'ConfigFileFinder.ignore_config_files'

Now that the `ConfigFileFinder` has the `.ignore_config_files`
attribute, switch the relevant code paths to utilize this public
attribute.

Tests have been updated to either construct `ConfigFileFinder` or mock
the object appropriately.
---
 src/flake8/options/config.py            | 4 ++--
 tests/integration/test_aggregator.py    | 3 ++-
 tests/unit/test_get_local_plugins.py    | 1 +
 tests/unit/test_merged_config_parser.py | 1 +
 4 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/flake8/options/config.py b/src/flake8/options/config.py
index e921f6e..ead12dc 100644
--- a/src/flake8/options/config.py
+++ b/src/flake8/options/config.py
@@ -307,7 +307,7 @@ class MergedConfigParser(object):
         :rtype:
             dict
         """
-        if isolated:
+        if self.config_finder.ignore_config_files:
             LOG.debug(
                 "Refusing to parse configuration files due to user-"
                 "requested isolation"
@@ -344,7 +344,7 @@ def get_local_plugins(config_finder, cli_config=None, isolated=False):
         flake8.options.config.LocalPlugins
     """
     local_plugins = LocalPlugins(extension=[], report=[], paths=[])
-    if isolated:
+    if config_finder.ignore_config_files:
         LOG.debug(
             "Refusing to look for local plugins in configuration"
             "files due to user-requested isolation"
diff --git a/tests/integration/test_aggregator.py b/tests/integration/test_aggregator.py
index 18ce5e8..636b3d5 100644
--- a/tests/integration/test_aggregator.py
+++ b/tests/integration/test_aggregator.py
@@ -43,7 +43,8 @@ def test_aggregate_options_when_isolated(optmanager):
     """Verify we aggregate options and config values appropriately."""
     arguments = ['flake8', '--select', 'E11,E34,E402,W,F',
                  '--exclude', 'tests/*']
-    config_finder = config.ConfigFileFinder('flake8', [])
+    config_finder = config.ConfigFileFinder(
+        'flake8', [], ignore_config_files=True)
     optmanager.extend_default_ignore(['E8'])
     options, args = aggregator.aggregate_options(
         optmanager, config_finder, None, True, arguments)
diff --git a/tests/unit/test_get_local_plugins.py b/tests/unit/test_get_local_plugins.py
index fa9c1a4..db62e33 100644
--- a/tests/unit/test_get_local_plugins.py
+++ b/tests/unit/test_get_local_plugins.py
@@ -21,6 +21,7 @@ def test_get_local_plugins_uses_cli_config():
     config_obj = mock.Mock()
     config_finder = mock.MagicMock()
     config_finder.cli_config.return_value = config_obj
+    config_finder.ignore_config_files = False
     config_obj.get.return_value = ''
 
     config.get_local_plugins(config_finder, cli_config='foo.ini')
diff --git a/tests/unit/test_merged_config_parser.py b/tests/unit/test_merged_config_parser.py
index a28a4c3..186d853 100644
--- a/tests/unit/test_merged_config_parser.py
+++ b/tests/unit/test_merged_config_parser.py
@@ -155,6 +155,7 @@ def test_parse_isolates_config(optmanager):
 def test_parse_uses_cli_config(optmanager):
     """Verify behaviour of the parse method with a specified config."""
     config_finder = mock.MagicMock()
+    config_finder.ignore_config_files = False
     parser = config.MergedConfigParser(optmanager, config_finder)
 
     parser.parse(cli_config='foo.ini')

From c918e7249699ab91ccbd6d69a898d19aa009c971 Mon Sep 17 00:00:00 2001
From: "Eric N. Vander Weele" <ericvw@gmail.com>
Date: Tue, 7 Jan 2020 13:14:34 -0500
Subject: [PATCH 3/3] Remove unused 'isolated' parameter

Now that `ConfigFileFinder.ignore_config_files` attribute is used
everywhere and is constructed from the `--isolated` CLI option, the now
unused `isolated` parameters can be safely removed.
---
 src/flake8/api/legacy.py                | 13 +++++-------
 src/flake8/main/application.py          | 27 ++++++-------------------
 src/flake8/options/aggregator.py        |  6 +-----
 src/flake8/options/config.py            | 10 ++-------
 tests/integration/test_aggregator.py    |  4 ++--
 tests/unit/test_get_local_plugins.py    |  3 ++-
 tests/unit/test_legacy_api.py           |  4 ++--
 tests/unit/test_merged_config_parser.py |  3 ++-
 8 files changed, 22 insertions(+), 48 deletions(-)

diff --git a/src/flake8/api/legacy.py b/src/flake8/api/legacy.py
index fe3b405..40da7db 100644
--- a/src/flake8/api/legacy.py
+++ b/src/flake8/api/legacy.py
@@ -32,18 +32,15 @@ def get_style_guide(**kwargs):
     prelim_opts, remaining_args = application.parse_preliminary_options([])
     flake8.configure_logging(prelim_opts.verbose, prelim_opts.output_file)
     config_finder = config.ConfigFileFinder(
-        application.program, prelim_opts.append_config
+        application.program,
+        prelim_opts.append_config,
+        ignore_config_files=prelim_opts.isolated,
     )
 
-    application.find_plugins(
-        config_finder, prelim_opts.config, prelim_opts.isolated
-    )
+    application.find_plugins(config_finder, prelim_opts.config)
     application.register_plugin_options()
     application.parse_configuration_and_cli(
-        config_finder,
-        prelim_opts.config,
-        prelim_opts.isolated,
-        remaining_args,
+        config_finder, prelim_opts.config, remaining_args,
     )
     # We basically want application.initialize to be called but with these
     # options set instead before we make our formatter, notifier, internal
diff --git a/src/flake8/main/application.py b/src/flake8/main/application.py
index 7ea3fbb..a30f195 100644
--- a/src/flake8/main/application.py
+++ b/src/flake8/main/application.py
@@ -131,8 +131,8 @@ class Application(object):
                 (self.result_count > 0) or self.catastrophic_failure
             )
 
-    def find_plugins(self, config_finder, config_file, ignore_config_files):
-        # type: (config.ConfigFileFinder, Optional[str], bool) -> None
+    def find_plugins(self, config_finder, config_file):
+        # type: (config.ConfigFileFinder, Optional[str]) -> None
         """Find and load the plugins for this application.
 
         Set the :attr:`check_plugins` and :attr:`formatting_plugins` attributes
@@ -147,9 +147,7 @@ class Application(object):
             Determine whether to parse configuration files or not. (i.e., the
             --isolated option).
         """
-        local_plugins = config.get_local_plugins(
-            config_finder, config_file, ignore_config_files
-        )
+        local_plugins = config.get_local_plugins(config_finder, config_file)
 
         sys.path.extend(local_plugins.paths)
 
@@ -173,7 +171,6 @@ class Application(object):
         self,
         config_finder,  # type: config.ConfigFileFinder
         config_file,  # type: Optional[str]
-        ignore_config_files,  # type: bool
         argv,  # type: List[str]
     ):
         # type: (...) -> None
@@ -184,18 +181,11 @@ class Application(object):
         :param str config_file:
             The optional configuraiton file to override all other configuration
             files (i.e., the --config option).
-        :param bool ignore_config_files:
-            Determine whether to parse configuration files or not. (i.e., the
-            --isolated option).
         :param list argv:
             Command-line arguments passed in directly.
         """
         self.options, self.args = aggregator.aggregate_options(
-            self.option_manager,
-            config_finder,
-            config_file,
-            ignore_config_files,
-            argv,
+            self.option_manager, config_finder, config_file, argv,
         )
 
         self.running_against_diff = self.options.diff
@@ -339,15 +329,10 @@ class Application(object):
             prelim_opts.append_config,
             ignore_config_files=prelim_opts.isolated,
         )
-        self.find_plugins(
-            config_finder, prelim_opts.config, prelim_opts.isolated
-        )
+        self.find_plugins(config_finder, prelim_opts.config)
         self.register_plugin_options()
         self.parse_configuration_and_cli(
-            config_finder,
-            prelim_opts.config,
-            prelim_opts.isolated,
-            remaining_args,
+            config_finder, prelim_opts.config, remaining_args,
         )
         self.make_formatter()
         self.make_guide()
diff --git a/src/flake8/options/aggregator.py b/src/flake8/options/aggregator.py
index 58d1022..939dfb3 100644
--- a/src/flake8/options/aggregator.py
+++ b/src/flake8/options/aggregator.py
@@ -17,7 +17,6 @@ def aggregate_options(
     manager,  # type: OptionManager
     config_finder,  # type: config.ConfigFileFinder
     cli_config,  # type: Optional[str]
-    isolated,  # type: bool
     argv,  # type: List[str]
 ):  # type: (...) -> Tuple[argparse.Namespace, List[str]]
     """Aggregate and merge CLI and config file options.
@@ -29,9 +28,6 @@ def aggregate_options(
     :param str cli_config:
         Value of --config when specified at the command-line. Overrides
         all other config files.
-    :param bool isolated:
-        Determines if we should parse configuration files at all or not.
-        If running in isolated mode, we ignore all configuration files
     :param list argv:
         The list of remaining command-line argumentsthat were unknown during
         preliminary option parsing to pass to ``manager.parse_args``.
@@ -50,7 +46,7 @@ def aggregate_options(
     )
 
     # Get the parsed config
-    parsed_config = config_parser.parse(cli_config, isolated)
+    parsed_config = config_parser.parse(cli_config)
 
     # Extend the default ignore value with the extended default ignore list,
     # registered by plugins.
diff --git a/src/flake8/options/config.py b/src/flake8/options/config.py
index ead12dc..7261bcd 100644
--- a/src/flake8/options/config.py
+++ b/src/flake8/options/config.py
@@ -289,7 +289,7 @@ class MergedConfigParser(object):
 
         return config
 
-    def parse(self, cli_config=None, isolated=False):
+    def parse(self, cli_config=None):
         """Parse and return the local and user config files.
 
         First this copies over the parsed local configuration and then
@@ -299,9 +299,6 @@ class MergedConfigParser(object):
         :param str cli_config:
             Value of --config when specified at the command-line. Overrides
             all other config files.
-        :param bool isolated:
-            Determines if we should parse configuration files at all or not.
-            If running in isolated mode, we ignore all configuration files
         :returns:
             Dictionary of parsed configuration options
         :rtype:
@@ -326,7 +323,7 @@ class MergedConfigParser(object):
         return self.merge_user_and_local_config()
 
 
-def get_local_plugins(config_finder, cli_config=None, isolated=False):
+def get_local_plugins(config_finder, cli_config=None):
     """Get local plugins lists from config files.
 
     :param flake8.options.config.ConfigFileFinder config_finder:
@@ -334,9 +331,6 @@ def get_local_plugins(config_finder, cli_config=None, isolated=False):
     :param str cli_config:
         Value of --config when specified at the command-line. Overrides
         all other config files.
-    :param bool isolated:
-        Determines if we should parse configuration files at all or not.
-        If running in isolated mode, we ignore all configuration files
     :returns:
         LocalPlugins namedtuple containing two lists of plugin strings,
         one for extension (checker) plugins and one for report plugins.
diff --git a/tests/integration/test_aggregator.py b/tests/integration/test_aggregator.py
index 636b3d5..672c865 100644
--- a/tests/integration/test_aggregator.py
+++ b/tests/integration/test_aggregator.py
@@ -32,7 +32,7 @@ def test_aggregate_options_with_config(optmanager):
                  'E11,E34,E402,W,F', '--exclude', 'tests/*']
     config_finder = config.ConfigFileFinder('flake8', [])
     options, args = aggregator.aggregate_options(
-        optmanager, config_finder, CLI_SPECIFIED_CONFIG, False, arguments)
+        optmanager, config_finder, CLI_SPECIFIED_CONFIG, arguments)
 
     assert options.select == ['E11', 'E34', 'E402', 'W', 'F']
     assert options.ignore == ['E123', 'W234', 'E111']
@@ -47,7 +47,7 @@ def test_aggregate_options_when_isolated(optmanager):
         'flake8', [], ignore_config_files=True)
     optmanager.extend_default_ignore(['E8'])
     options, args = aggregator.aggregate_options(
-        optmanager, config_finder, None, True, arguments)
+        optmanager, config_finder, None, arguments)
 
     assert options.select == ['E11', 'E34', 'E402', 'W', 'F']
     assert sorted(options.ignore) == [
diff --git a/tests/unit/test_get_local_plugins.py b/tests/unit/test_get_local_plugins.py
index db62e33..6311677 100644
--- a/tests/unit/test_get_local_plugins.py
+++ b/tests/unit/test_get_local_plugins.py
@@ -7,8 +7,9 @@ from flake8.options import config
 def test_get_local_plugins_respects_isolated():
     """Verify behaviour of get_local_plugins with isolated=True."""
     config_finder = mock.MagicMock()
+    config_finder.ignore_config_files = True
 
-    local_plugins = config.get_local_plugins(config_finder, isolated=True)
+    local_plugins = config.get_local_plugins(config_finder)
 
     assert local_plugins.extension == []
     assert local_plugins.report == []
diff --git a/tests/unit/test_legacy_api.py b/tests/unit/test_legacy_api.py
index d3b9eb5..2ec836c 100644
--- a/tests/unit/test_legacy_api.py
+++ b/tests/unit/test_legacy_api.py
@@ -31,10 +31,10 @@ def test_get_style_guide():
 
     application.assert_called_once_with()
     mockedapp.parse_preliminary_options.assert_called_once_with([])
-    mockedapp.find_plugins.assert_called_once_with(config_finder, None, False)
+    mockedapp.find_plugins.assert_called_once_with(config_finder, None)
     mockedapp.register_plugin_options.assert_called_once_with()
     mockedapp.parse_configuration_and_cli.assert_called_once_with(
-        config_finder, None, False, [])
+        config_finder, None, [])
     mockedapp.make_formatter.assert_called_once_with()
     mockedapp.make_guide.assert_called_once_with()
     mockedapp.make_file_checker_manager.assert_called_once_with()
diff --git a/tests/unit/test_merged_config_parser.py b/tests/unit/test_merged_config_parser.py
index 186d853..f2d70d9 100644
--- a/tests/unit/test_merged_config_parser.py
+++ b/tests/unit/test_merged_config_parser.py
@@ -145,9 +145,10 @@ def test_merge_user_and_local_config(optmanager, config_finder):
 def test_parse_isolates_config(optmanager):
     """Verify behaviour of the parse method with isolated=True."""
     config_finder = mock.MagicMock()
+    config_finder.ignore_config_files = True
     parser = config.MergedConfigParser(optmanager, config_finder)
 
-    assert parser.parse(isolated=True) == {}
+    assert parser.parse() == {}
     assert config_finder.local_configs.called is False
     assert config_finder.user_config.called is False