Refactor FileManager.select_file() to @filename.setter property

lib/tfw/components/source_code_event_handler.py

@@ -10,9 +10,9 @@ log = logging.getLogger(__name__)
 
 class FileManager:
     def __init__(self, working_directory, selected_file=None, exclude=()):
-        self._exclude, self.exclude = None, exclude
+        self._exclude, self.exclude = None, *exclude
         self._workdir, self.workdir = None, working_directory
-        self.filename = selected_file or self.files[0]
+        self._filename, self.filename = None, selected_file or self.files[0]
 
     @property
     def exclude(self):
@@ -32,10 +32,15 @@ class FileManager:
             raise EnvironmentError('"{}" is not a directory!'.format(directory))
         self._workdir = directory
 
-    def select_file(self, filename):
+    @property
+    def filename(self):
+        return self._filename
+
+    @filename.setter
+    def filename(self, filename):
         if not filename in self.files:
            raise EnvironmentError('No such file in workdir!')
-        self.filename = filename
+        self._filename = filename
 
     @property
     def files(self):
@@ -99,7 +104,7 @@ class SourceCodeEventHandler(TriggerlessEventHandler):
         return data
 
     def select(self, data):
-        try: self.filemanager.select_file(data['filename'])
+        try: self.filemanager.filename = data['filename']
         except EnvironmentError: log.exception('Failed to select file "{}"'.format(data['filename']))
         return data
 
@@ -108,7 +113,7 @@ class SourceCodeEventHandler(TriggerlessEventHandler):
             self.filemanager.workdir = data['directory']
             self.reload_monitor()
             try:
-                self.filemanager.select_file(self.filemanager.files[0])
+                self.filemanager.filename = self.filemanager.files[0]
                 self.read(data)
             except IndexError:
                 data['content'] = 'No files in this directory :('