Fix up merge request 78

This simplifies the changes, reduces the scope of refactors apparently
for refactoring's sake and ensures that the internals are reasonable.

It also airs on the side of preserving information rather than
discarding or overwriting it.

src/flake8/checker.py

@@ -234,15 +234,14 @@ class Manager(object):
         :rtype:
             bool
         """
+        if path == '-':
+            if self.options.stdin_display_name == 'stdin':
+                return False
+            path = self.options.stdin_display_name
+
         exclude = self.options.exclude
         if not exclude:
             return False
-        if path == '-':
-            # stdin, use display name to check exclusion, if present
-            path = self.options.stdin_display_name
-            if path is None:
-                LOG.debug("unnamed stdin has not been excluded")
-                return False
         basename = os.path.basename(path)
         if utils.fnmatch(basename, exclude):
             LOG.debug('"%s" has been excluded', basename)
@@ -269,14 +268,15 @@ class Manager(object):
         # best solution right now.
         def should_create_file_checker(filename):
             """Determine if we should create a file checker."""
-            return (
-                filename == '-' or  # stdin
-                utils.fnmatch(filename, filename_patterns) and
-                os.path.exists(filename)
+            matches_filename_patterns = utils.fnmatch(
+                filename, filename_patterns
             )
+            is_stdin = filename == '-'
+            file_exists = os.path.exists(filename)
+            return (file_exists and matches_filename_patterns) or is_stdin
 
         self.checkers = [
-            FileChecker(filename, self.checks, self.style_guide)
+            FileChecker(filename, self.checks, self.options)
             for argument in paths
             for filename in utils.filenames_from(argument,
                                                  self.is_path_excluded)
@@ -299,7 +299,7 @@ class Manager(object):
         results_reported = results_found = 0
         for checker in self.checkers:
             results = sorted(checker.results, key=lambda tup: (tup[2], tup[3]))
-            results_reported += self._handle_results(checker.filename,
+            results_reported += self._handle_results(checker.display_name,
                                                      results)
             results_found += len(results)
         return (results_found, results_reported)
@@ -320,9 +320,9 @@ class Manager(object):
             final_results[filename] = results
 
         for checker in self.checkers:
-            filename = checker.filename
+            filename = checker.display_name
             checker.results = sorted(final_results.get(filename, []),
-                                     key=lambda tup: (tup[1], tup[2]))
+                                     key=lambda tup: (tup[2], tup[2]))
 
     def run_serial(self):
         """Run the checkers in serial."""
@@ -384,7 +384,7 @@ class Manager(object):
 class FileChecker(object):
     """Manage running checks for a file and aggregate the results."""
 
-    def __init__(self, filename, checks, style_guide):
+    def __init__(self, filename, checks, options):
         """Initialize our file checker.
 
         :param str filename:
@@ -393,26 +393,26 @@ class FileChecker(object):
             The plugins registered to check the file.
         :type checks:
             flake8.plugins.manager.Checkers
-        :param style_guide:
-            The initialized StyleGuide for this particular run.
-        :type style_guide:
-            flake8.style_guide.StyleGuide
+        :param options:
+            Parsed option values from config and command-line.
+        :type options:
+            optparse.Values
         """
+        self.options = options
+        self.filename = filename
         self.checks = checks
-        self.style_guide = style_guide
         self.results = []
-        self.processor = self._make_processor(filename)
-        self.filename = self.processor.filename
+        self.processor = self._make_processor()
+        self.display_name = self.processor.filename
         self.statistics = {
             'tokens': 0,
             'logical lines': 0,
             'physical lines': len(self.processor.lines),
         }
 
-    def _make_processor(self, filename):
+    def _make_processor(self):
         try:
-            return processor.FileProcessor(filename,
-                                           self.style_guide.options)
+            return processor.FileProcessor(self.filename, self.options)
         except IOError:
             # If we can not read the file due to an IOError (e.g., the file
             # does not exist or we do not have the permissions to open it)

src/flake8/main/options.py

@@ -74,7 +74,7 @@ def register_default_options(option_manager):
     )
 
     add_option(
-        '--stdin-display-name',
+        '--stdin-display-name', default='stdin',
         help='The name used when reporting errors from code passed via stdin.'
              ' This is useful for editors piping the file contents to flake8.'
              ' (Default: %default)',

src/flake8/processor.py

@@ -59,8 +59,7 @@ class FileProcessor(object):
         self.filename = filename
         self.lines = lines
         if lines is None:
-            # allow for stdin filename substitution
-            self.filename, self.lines = self.read_lines(filename)
+            self.lines = self.read_lines()
         self.strip_utf_bom()
 
         # Defaults for public attributes
@@ -269,15 +268,15 @@ class FileProcessor(object):
             self.indent_char = line[0]
         return line
 
-    def read_lines(self, filename):
+    def read_lines(self):
         # type: () -> List[str]
         """Read the lines for this file checker."""
-        if filename is None or filename == '-':
-            filename = self.options.stdin_display_name or 'stdin'
+        if self.filename is None or self.filename == '-':
+            self.filename = self.options.stdin_display_name
             lines = self.read_lines_from_stdin()
         else:
             lines = self.read_lines_from_filename()
-        return (filename, lines)
+        return lines
 
     def _readlines_py2(self):
         # type: () -> List[str]

src/flake8/utils.py

@@ -212,22 +212,24 @@ def filenames_from(arg, predicate=None):
     if predicate(arg):
         return
 
-    if arg == "-":
-        # stdin, don't call isdir()
-        yield arg
-    elif os.path.isdir(arg):
+    if os.path.isdir(arg):
         for root, sub_directories, files in os.walk(arg):
+            if predicate(root):
+                sub_directories[:] = []
+                continue
+
             # NOTE(sigmavirus24): os.walk() will skip a directory if you
             # remove it from the list of sub-directories.
-            sub_directories[:] = [
-                directory for directory in sub_directories
-                if not predicate(os.path.join(root, directory))
-            ]
+            for directory in sub_directories:
+                joined = os.path.join(root, directory)
+                if predicate(directory) or predicate(joined):
+                    sub_directories.remove(directory)
 
             for filename in files:
                 joined = os.path.join(root, filename)
-                if not predicate(joined):
-                    yield joined
+                if predicate(joined) or predicate(filename):
+                    continue
+                yield joined
     else:
         yield arg
 

tests/unit/test_file_processor.py

@@ -14,7 +14,7 @@ def options_from(**kwargs):
     kwargs.setdefault('hang_closing', True)
     kwargs.setdefault('max_line_length', 79)
     kwargs.setdefault('verbose', False)
-    kwargs.setdefault('stdin_display_name', None)
+    kwargs.setdefault('stdin_display_name', 'stdin')
     return optparse.Values(kwargs)
 
 
@@ -71,10 +71,18 @@ def test_stdin_filename_attribute(stdin_get_value):
     stdin_get_value.return_value = stdin_value
     file_processor = processor.FileProcessor('-', options_from())
     assert file_processor.filename == 'stdin'
+
+
+@mock.patch('flake8.utils.stdin_get_value')
+def test_read_lines_uses_display_name(stdin_get_value):
+    """Verify that when processing stdin we use a display name if present."""
+    stdin_value = mock.Mock()
+    stdin_value.splitlines.return_value = []
+    stdin_get_value.return_value = stdin_value
     file_processor = processor.FileProcessor('-', options_from(
-        stdin_display_name="foo.py"
+        stdin_display_name='display_name.py'
     ))
-    assert file_processor.filename == 'foo.py'
+    assert file_processor.filename == 'display_name.py'
 
 
 def test_line_for():