Make the default session name configurable.

See #523.

doc/help/commands.asciidoc

@@ -439,7 +439,8 @@ Syntax: +:session-save [*--current*] [*--quiet*] [*--force*] ['name']+
 Save a session.
 
 ==== positional arguments
-* +'name'+: The name of the session.
+* +'name'+: The name of the session. If not given, the session configured in general -> session-default-name is saved.
+
 
 ==== optional arguments
 * +*-c*+, +*--current*+: Save the current session instead of the default.

doc/help/settings.asciidoc

@@ -22,6 +22,7 @@
 |<<general-new-instance-open-target,new-instance-open-target>>|How to open links in an existing instance if a new one is launched.
 |<<general-log-javascript-console,log-javascript-console>>|Whether to log javascript console messages.
 |<<general-save-session,save-session>>|Whether to always save the open pages.
+|<<general-session-default-name,session-default-name>>|The name of the session to save by default, or empty for the last loaded session.
 |==============
 
 .Quick reference for section ``ui''
@@ -419,6 +420,12 @@ Valid values:
 
 Default: +pass:[false]+
 
+[[general-session-default-name]]
+=== session-default-name
+The name of the session to save by default, or empty for the last loaded session.
+
+Default: +pass:[default]+
+
 == ui
 General options related to the user interface.
 

qutebrowser/app.py

@@ -829,7 +829,7 @@ class Application(QApplication):
 
     @cmdutils.register(instance='app', name='wq',
                        completion=[usertypes.Completion.sessions])
-    def save_and_quit(self, name='default'):
+    def save_and_quit(self, name=sessions.default):
         """Save open pages and quit.
 
         Args:
@@ -863,7 +863,7 @@ class Application(QApplication):
             session_manager.save(session, last_window=last_window,
                                  load_next_time=True)
         elif config.get('general', 'save-session'):
-            session_manager.save('default', last_window=last_window,
+            session_manager.save(sessions.default, last_window=last_window,
                                  load_next_time=True)
 
         deferrer = False

qutebrowser/config/configdata.py

@@ -216,6 +216,11 @@ def data(readonly=False):
              SettingValue(typ.Bool(), 'false'),
              "Whether to always save the open pages."),
 
+            ('session-default-name',
+             SettingValue(typ.SessionName(none_ok=True), ''),
+             "The name of the session to save by default, or empty for the "
+             "last loaded session."),
+
             readonly=readonly
         )),
 

qutebrowser/config/configtypes.py

@@ -1294,6 +1294,22 @@ class UrlList(List):
                                                 "{}".format(val.errorString()))
 
 
+class SessionName(BaseType):
+
+    """The name of a session."""
+
+    typestr = 'session'
+
+    def validate(self, value):
+        if not value:
+            if self._none_ok:
+                return
+            else:
+                raise configexc.ValidationError(value, "may not be empty!")
+        if value.startswith('_'):
+            raise configexc.ValidationError(value, "may not start with '_'!")
+
+
 class SelectOnRemove(BaseType):
 
     """Which tab to select when the focused tab is removed."""

qutebrowser/misc/sessions.py

@@ -35,6 +35,10 @@ from qutebrowser.utils import (standarddir, objreg, qtutils, log, usertypes,
                                message)
 from qutebrowser.commands import cmdexc, cmdutils
 from qutebrowser.mainwindow import mainwindow
+from qutebrowser.config import config
+
+
+default = object()  # Sentinel value
 
 
 class SessionError(Exception):
@@ -163,10 +167,22 @@ class SessionManager(QObject):
         """Save a named session.
 
         Args:
+            name: The name of the session to save, or the 'default' sentinel
+                  object.
             last_window: If set, saves the saved self._last_window_session
                          instead of the currently open state.
             load_next_time: If set, prepares this session to be load next time.
+
+        Return:
+            The name of the saved session.
         """
+        if name is default:
+            name = config.get('general', 'session-default-name')
+            if name is None:
+                if self._current is not None:
+                    name = self._current
+                else:
+                    name = 'default'
         path = self._get_session_path(name)
 
         log.misc.debug("Saving session {} to {}...".format(name, path))
@@ -187,6 +203,7 @@ class SessionManager(QObject):
         if load_next_time:
             state_config = objreg.get('state-config')
             state_config['general']['session'] = name
+        return name
 
     def save_last_window_session(self):
         """Temporarily save the session for the last closed window."""
@@ -299,18 +316,22 @@ class SessionManager(QObject):
     @cmdutils.register(name=['session-save', 'w'],
                        completion=[usertypes.Completion.sessions],
                        instance='session-manager')
-    def session_save(self, win_id: {'special': 'win_id'}, name='default',
+    def session_save(self, win_id: {'special': 'win_id'},
-                     current=False, quiet=False, force=False):
+                     name: {'type': str}=default, current=False, quiet=False,
+                     force=False):
         """Save a session.
 
         Args:
             win_id: The current window ID.
-            name: The name of the session.
+            name: The name of the session. If not given, the session configured
+                  in general -> session-default-name is saved.
             current: Save the current session instead of the default.
             quiet: Don't show confirmation message.
             force: Force saving internal sessions (starting with an underline).
         """
-        if name.startswith('_') and not force:
+        if (name is not default and
+                name.startswith('_') and  # pylint: disable=no-member
+                not force):
             raise cmdexc.CommandError("{!r} is an internal session, use "
                                       "--force to save anyways.".format(name))
         if current:
@@ -319,7 +340,7 @@ class SessionManager(QObject):
             name = self._current
             assert not name.startswith('_')
         try:
-            self.save(name)
+            name = self.save(name)
         except SessionError as e:
             raise cmdexc.CommandError("Error while saving session: {}"
                                       .format(e))