Refactor standarddir.

See #941.

qutebrowser/utils/standarddir.py

@@ -32,33 +32,84 @@ _args = None
 
 
 def config():
-    """Convenience function to get the config location."""
+    """Get a location for configs."""
-    return _get(QStandardPaths.ConfigLocation)
+    typ = QStandardPaths.ConfigLocation
+    overridden, path = _from_args(typ, _args)
+    if not overridden:
+        path = _writable_location(typ)
+        appname = QCoreApplication.instance().applicationName()
+        if path.split(os.sep)[-1] != appname:
+            # WORKAROUND - see
+            # https://bugreports.qt.io/browse/QTBUG-38872
+            path = os.path.join(path, appname)
+    _maybe_create(path)
+    return path
 
 
 def data():
-    """Convenience function to get the data location."""
+    """Get a location for data."""
-    return _get(QStandardPaths.DataLocation)
+    typ = QStandardPaths.DataLocation
+    overridden, path = _from_args(typ, _args)
+    if not overridden:
+        path = _writable_location(typ)
+        if os.name == 'nt':
+            # Under windows, config/data might end up in the same directory.
+            data_path = QStandardPaths.writableLocation(
+                QStandardPaths.DataLocation)
+            config_path = QStandardPaths.writableLocation(
+                QStandardPaths.ConfigLocation)
+            if data_path == config_path:
+                path = os.path.join(path, 'data')
+    _maybe_create(path)
+    return path
 
 
 def cache():
-    """Convenience function to get the cache location."""
+    """Get a location for the cache."""
-    return _get(QStandardPaths.CacheLocation)
+    typ = QStandardPaths.CacheLocation
+    overridden, path = _from_args(typ, _args)
+    if not overridden:
+        path = _writable_location(typ)
+    _maybe_create(path)
+    return path
 
 
 def download():
-    """Convenience function to get the download location."""
+    """Get a location for downloads."""
-    return _get(QStandardPaths.DownloadLocation)
+    typ = QStandardPaths.DownloadLocation
+    overridden, path = _from_args(typ, _args)
+    if not overridden:
+        path = _writable_location(typ)
+    _maybe_create(path)
+    return path
 
 
 def runtime():
-    """Convenience function to get the runtime location."""
+    """Get a location for runtime data."""
-    return _get(QStandardPaths.RuntimeLocation)
+    typ = QStandardPaths.RuntimeLocation
+    overridden, path = _from_args(typ, _args)
+    if not overridden:
+        path = _writable_location(typ)
+        # This is generic, but per-user.
+        appname = QCoreApplication.instance().applicationName()
+        path = os.path.join(path, appname)
+    _maybe_create(path)
+    return path
 
 
 def temp():
-    """Convenience function to get the temporary files location."""
+    """Get a location for temporary files."""
-    return _get(QStandardPaths.TempLocation)
+    typ = QStandardPaths.TempLocation
+    path = _writable_location(typ)
+    # "The returned value might be application-specific, shared among
+    # other applications for this user, or even system-wide."
+    #
+    # Unfortunately this path could get too long for IPC sockets, so we
+    # don't add the username here...
+    appname = QCoreApplication.instance().applicationName()
+    path = os.path.join(path, appname)
+    _maybe_create(path)
+    return path
 
 
 def _writable_location(typ):
@@ -122,53 +173,20 @@ def _from_args(typ, args):
         return (True, arg_value)
 
 
-def _get(typ):
+def _maybe_create(path):
-    """Get the directory where files of the given type should be written to.
+    """Create the `path` directory if path is not None.
 
-    Args:
+    From the XDG basedir spec:
-        typ: A member of the QStandardPaths::StandardLocation enum,
+        If, when attempting to write a file, the destination directory is
-             see http://doc.qt.io/qt-5/qstandardpaths.html#StandardLocation-enum
+        non-existant an attempt should be made to create it with permission
+        0700. If the destination directory exists already the permissions
+        should not be changed.
     """
-    overridden, path = _from_args(typ, _args)
-    if not overridden:
-        path = _writable_location(typ)
-        appname = QCoreApplication.instance().applicationName()
-
-        if (typ == QStandardPaths.ConfigLocation and
-                path.split(os.sep)[-1] != appname):
-            # WORKAROUND - see
-            # https://bugreports.qt.io/browse/QTBUG-38872
-            path = os.path.join(path, appname)
-        elif typ == QStandardPaths.DataLocation and os.name == 'nt':
-            # Under windows, config/data might end up in the same directory.
-            data_path = QStandardPaths.writableLocation(
-                QStandardPaths.DataLocation)
-            config_path = QStandardPaths.writableLocation(
-                QStandardPaths.ConfigLocation)
-            if data_path == config_path:
-                path = os.path.join(path, 'data')
-        elif typ == QStandardPaths.TempLocation:
-            # "The returned value might be application-specific, shared among
-            # other applications for this user, or even system-wide."
-            #
-            # Unfortunately this path could get too long for IPC sockets, so we
-            # don't add the username here...
-            subdir = appname
-            path = os.path.join(path, subdir)
-        elif typ == QStandardPaths.RuntimeLocation:
-            # This is generic, but per-user.
-            path = os.path.join(path, appname)
-    # From the XDG basedir spec:
-    #     If, when attempting to write a file, the destination directory is
-    #     non-existant an attempt should be made to create it with permission
-    #     0700. If the destination directory exists already the permissions
-    #     should not be changed.
     if path is not None:
         try:
             os.makedirs(path, 0o700)
         except FileExistsError:
             pass
-    return path
 
 
 def init(args):