Moved parallel code outside of PyLinter

pylint/lint.py

@@ -193,7 +193,7 @@ MSGS = {
 if multiprocessing is not None:
-    class ChildLinter(multiprocessing.Process):
+    class ChildRunner(multiprocessing.Process):
         def run(self):
             # pylint: disable=no-member, unbalanced-tuple-unpacking
             tasks_queue, results_queue, self._config = self._args
@@ -717,115 +717,23 @@ class PyLinter(config.OptionsManagerMixIn,
         return path.endswith('.py')
     # pylint: enable=unused-argument
+    def _init_msg_states(self):
+        for msg in self.msgs_store.messages:
+            if not msg.may_be_emitted():
+                self._msgs_state[msg.msgid] = False
+
     def check(self, files_or_modules):
         """main checking entry: check a list of files or modules from their
         name.
         """
         # initialize msgs_state now that all messages have been registered into
         # the store
-        for msg in self.msgs_store.messages:
-            if not msg.may_be_emitted():
-                self._msgs_state[msg.msgid] = False
+        self._init_msg_states()
         if not isinstance(files_or_modules, (list, tuple)):
             files_or_modules = (files_or_modules,)
-        if self.config.jobs == 1:
-            self._do_check(files_or_modules)
-        else:
-            with _patch_sysmodules():
-                self._parallel_check(files_or_modules)
-
-    def _get_jobs_config(self):
-        child_config = collections.OrderedDict()
-        filter_options = {'long-help'}
-        filter_options.update((opt_name for opt_name, _ in self._external_opts))
-        for opt_providers in six.itervalues(self._all_options):
-            for optname, optdict, val in opt_providers.options_and_values():
-                if optdict.get('deprecated'):
-                    continue
-
-                if optname not in filter_options:
-                    child_config[optname] = utils._format_option_value(
-                        optdict, val)
-        child_config['python3_porting_mode'] = self._python3_porting_mode
-        child_config['plugins'] = self._dynamic_plugins
-        return child_config
-
-    def _parallel_task(self, files_or_modules):
-        # Prepare configuration for child linters.
-        child_config = self._get_jobs_config()
-
-        children = []
-        manager = multiprocessing.Manager()
-        tasks_queue = manager.Queue()
-        results_queue = manager.Queue()
-
-        for _ in range(self.config.jobs):
-            child_linter = ChildLinter(args=(tasks_queue, results_queue,
-                                             child_config))
-            child_linter.start()
-            children.append(child_linter)
-
-        # Send files to child linters.
-        expanded_files = utils.expand_files(files_or_modules, self, self.config.black_list, self.config.black_list_re)
-        for module_desc in expanded_files:
-            tasks_queue.put([module_desc.path])
-
-        # collect results from child linters
-        failed = False
-        for _ in expanded_files:
-            try:
-                result = results_queue.get()
-            except Exception as ex:
-                print("internal error while receiving results from child linter",
-                      file=sys.stderr)
-                print(ex, file=sys.stderr)
-                failed = True
-                break
-            yield result
-
-        # Stop child linters and wait for their completion.
-        for _ in range(self.config.jobs):
-            tasks_queue.put('STOP')
-        for child in children:
-            child.join()
-
-        if failed:
-            print("Error occurred, stopping the linter.", file=sys.stderr)
-            sys.exit(32)
-
-    def _parallel_check(self, files_or_modules):
-        # Reset stats.
-        self.open()
-
-        all_stats = []
-        module = None
-        for result in self._parallel_task(files_or_modules):
-            (
-                _,
-                self.file_state.base_name,
-                module,
-                messages,
-                stats,
-                msg_status
-            ) = result
-
-            for msg in messages:
-                msg = utils.Message(*msg)
-                self.set_current_module(module)
-                self.reporter.handle_message(msg)
-
-            all_stats.append(stats)
-            self.msg_status |= msg_status
-
-        self.stats = _merge_stats(all_stats)
-        self.current_name = module
-
-        # Insert stats data to local checkers.
-        for checker in self.get_checkers():
-            if checker is not self:
-                checker.stats = self.stats
+        self._do_check(files_or_modules)
     def _do_check(self, files_or_modules):
         walker = utils.PyLintASTWalker(self)
@@ -1290,18 +1198,123 @@ group are mutually exclusive.'),
                 print("Multiprocessing library is missing, "
                       "fallback to single process", file=sys.stderr)
                 linter.set_option("jobs", 1)
-            else:
-                if linter.config.jobs == 0:
-                    linter.config.jobs = multiprocessing.cpu_count()
+            elif linter.config.jobs == 0:
+                linter.config.jobs = multiprocessing.cpu_count()
         # insert current working directory to the python path to have a correct
         # behaviour
         with fix_import_path(args):
-            linter.check(args)
+            if linter.config.jobs == 1:
+                linter.check(args)
+            else:
+                self._parallel_run(args)
+
             linter.generate_reports()
+
         if exit:
             sys.exit(self.linter.msg_status)
+    def _parallel_run(self, files_or_modules):
+        with _patch_sysmodules():
+            self.linter._init_msg_states()
+            self._parallel_check(files_or_modules)
+
+    def _parallel_task(self, files_or_modules):
+        # Prepare configuration for child linters.
+        child_config = self._get_jobs_config()
+
+        children = []
+        manager = multiprocessing.Manager()
+        tasks_queue = manager.Queue()
+        results_queue = manager.Queue()
+
+        for _ in range(self.linter.config.jobs):
+            child_linter = ChildRunner(args=(tasks_queue, results_queue,
+                                             child_config))
+            child_linter.start()
+            children.append(child_linter)
+
+        # Send files to child linters.
+        expanded_files = utils.expand_files(
+            files_or_modules,
+            self.linter,
+            self.linter.config.black_list,
+            self.linter.config.black_list_re
+        )
+        for module_desc in expanded_files:
+            tasks_queue.put([module_desc.path])
+
+        # collect results from child linters
+        failed = False
+        for _ in expanded_files:
+            try:
+                result = results_queue.get()
+            except Exception as ex:
+                print("internal error while receiving results from child linter",
+                      file=sys.stderr)
+                print(ex, file=sys.stderr)
+                failed = True
+                break
+            yield result
+
+        # Stop child linters and wait for their completion.
+        for _ in range(self.linter.config.jobs):
+            tasks_queue.put('STOP')
+        for child in children:
+            child.join()
+
+        if failed:
+            print("Error occured, stopping the linter.", file=sys.stderr)
+            sys.exit(32)
+
+    def _parallel_check(self, files_or_modules):
+        # Reset stats.
+        self.linter.open()
+
+        all_stats = []
+        module = None
+        for result in self._parallel_task(files_or_modules):
+            (
+                _,
+                self.linter.file_state.base_name,
+                module,
+                messages,
+                stats,
+                msg_status
+            ) = result
+
+            for msg in messages:
+                msg = utils.Message(*msg)
+                self.linter.set_current_module(module)
+                self.linter.reporter.handle_message(msg)
+
+            all_stats.append(stats)
+            self.linter.msg_status |= msg_status
+
+        self.linter.stats = _merge_stats(all_stats)
+        self.linter.current_name = module
+
+        # Insert stats data to local checkers.
+        for checker in self.linter.get_checkers():
+            if checker is not self.linter:
+                checker.stats = self.linter.stats
+
+    def _get_jobs_config(self):
+        child_config = collections.OrderedDict()
+        filter_options = {'long-help'}
+        filter_options.update((opt_name for opt_name, _ in self.linter._external_opts))
+        for opt_providers in six.itervalues(self.linter._all_options):
+            for optname, optdict, val in opt_providers.options_and_values():
+                if optdict.get('deprecated'):
+                    continue
+
+                if optname not in filter_options:
+                    child_config[optname] = utils._format_option_value(
+                        optdict, val)
+        child_config['python3_porting_mode'] = self.linter._python3_porting_mode
+        child_config['plugins'] = self.linter._dynamic_plugins
+        return child_config
+
     def cb_set_rcfile(self, name, value):
         """callback for option preprocessing (i.e. before option parsing)"""
         self._rcfile = value