Merge branch 'aggregator-config-isolated-fix' into 'master'

aggregator: Forward  --config and --isolated options during aggregation

Closes #605

See merge request pycqa/flake8!395

3 files changed, 41 insertions, 12 deletions

diff --git a/src/flake8/api/legacy.py b/src/flake8/api/legacy.py
index 2761163..fe3b405 100644
--- a/src/flake8/api/legacy.py
+++ b/src/flake8/api/legacy.py
@@ -39,7 +39,12 @@ def get_style_guide(**kwargs):
         config_finder, prelim_opts.config, prelim_opts.isolated
     )
     application.register_plugin_options()
-    application.parse_configuration_and_cli(config_finder, remaining_args)
+    application.parse_configuration_and_cli(
+        config_finder,
+        prelim_opts.config,
+        prelim_opts.isolated,
+        remaining_args,
+    )
     # We basically want application.initialize to be called but with these
     # options set instead before we make our formatter, notifier, internal
     # style guide and file checker manager.
diff --git a/src/flake8/main/application.py b/src/flake8/main/application.py
index 63db8e1..791d5af 100644
--- a/src/flake8/main/application.py
+++ b/src/flake8/main/application.py
@@ -169,17 +169,33 @@ class Application(object):
         self.check_plugins.register_plugin_versions(self.option_manager)
         self.formatting_plugins.register_options(self.option_manager)
 
-    def parse_configuration_and_cli(self, config_finder, argv):
-        # type: (config.ConfigFileFinder, List[str]) -> None
+    def parse_configuration_and_cli(
+        self,
+        config_finder,  # type: config.ConfigFileFinder
+        config_file,  # type: Optional[str]
+        ignore_config_files,  # type: bool
+        argv,  # type: List[str]
+    ):
+        # type: (...) -> None
         """Parse configuration files and the CLI options.
 
         :param config.ConfigFileFinder config_finder:
             The finder for finding and reading configuration files.
+        :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, argv
+            self.option_manager,
+            config_finder,
+            config_file,
+            ignore_config_files,
+            argv,
         )
 
         self.running_against_diff = self.options.diff
@@ -325,7 +341,12 @@ class Application(object):
             config_finder, prelim_opts.config, prelim_opts.isolated
         )
         self.register_plugin_options()
-        self.parse_configuration_and_cli(config_finder, remaining_args)
+        self.parse_configuration_and_cli(
+            config_finder,
+            prelim_opts.config,
+            prelim_opts.isolated,
+            remaining_args,
+        )
         self.make_formatter()
         self.make_guide()
         self.make_file_checker_manager()
diff --git a/src/flake8/options/aggregator.py b/src/flake8/options/aggregator.py
index 719160a..58d1022 100644
--- a/src/flake8/options/aggregator.py
+++ b/src/flake8/options/aggregator.py
@@ -5,7 +5,7 @@ applies the user-specified command-line configuration on top of it.
 """
 import argparse
 import logging
-from typing import List, Tuple
+from typing import List, Optional, Tuple
 
 from flake8.options import config
 from flake8.options.manager import OptionManager
@@ -16,6 +16,8 @@ LOG = logging.getLogger(__name__)
 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.
@@ -24,6 +26,12 @@ def aggregate_options(
         The instance of the OptionManager that we're presently using.
     :param flake8.options.config.ConfigFileFinder config_finder:
         The config file finder to use.
+    :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``.
@@ -35,9 +43,6 @@ def aggregate_options(
     """
     # Get defaults from the option parser
     default_values, _ = manager.parse_args([])
-    # Get original CLI values so we can find additional config file paths and
-    # see if --config was specified.
-    original_values, _ = manager.parse_args(argv)
 
     # Make our new configuration file mergerator
     config_parser = config.MergedConfigParser(
@@ -45,9 +50,7 @@ def aggregate_options(
     )
 
     # Get the parsed config
-    parsed_config = config_parser.parse(
-        original_values.config, original_values.isolated
-    )
+    parsed_config = config_parser.parse(cli_config, isolated)
 
     # Extend the default ignore value with the extended default ignore list,
     # registered by plugins.