library: Snap execution output to the bottom

Author: tchx84

src/gameeky/library/widgets/window.py

@@ -49,6 +49,7 @@ class Window(Adw.ApplicationWindow):
 
     source_buffer = Gtk.Template.Child()
     output_buffer = Gtk.Template.Child()
+    output_view = Gtk.Template.Child()
     execute_button = Gtk.Template.Child()
     stop_button = Gtk.Template.Child()
     banner = Gtk.Template.Child()
@@ -60,6 +61,9 @@ def __init__(self, *args, **kargs) -> None:
         self._handler_id = self.source_buffer.connect(
             "changed", self.__on_source_changed
         )
+        self._output_mark = self.output_buffer.create_mark(
+            None, self.output_buffer.get_end_iter(), False
+        )
 
         Monitor.default().connect("changed", self.__on_monitor_changed)
 
@@ -176,6 +180,7 @@ def __on_output(
             self._restore_ui()
         else:
             self.output_buffer.insert_at_cursor(data.decode("UTF-8") + "\n")
+            self.output_view.scroll_to_mark(self._output_mark, 0.0, False, 0.0, 0.0)
             self._queue_read(stream)
 
     def _restore_ui(self) -> None:

src/gameeky/library/widgets/window.ui

@@ -16,7 +16,7 @@
                 <property name="end-child">
                   <object class="GtkScrolledWindow">
                     <property name="child">
-                      <object class="GtkTextView">
+                      <object class="GtkTextView" id="output_view">
                         <property name="buffer">
                           <object class="GtkTextBuffer" id="output_buffer"/>
                         </property>