Shrink completion if configured to do so

TODO

@@ -55,7 +55,6 @@ Improvements / minor features
     - if a cookie is a http-only cookie domain is prepended with a #HttpOnly_
 - Zoom with ctrl + mousewheel
 - search highlighting
-- max height for completion (be smaller if possible)
 - vertical tabbar
 - reload config command
     - config changed signals for sections (optimization)

qutebrowser/config/configdata.py

@@ -270,6 +270,11 @@ DATA = OrderedDict([
          SettingValue(types.Bool(), 'true'),
          "Whether to move on to the next part when there's only one possible "
          "completion left."),
+
+        ('shrink',
+         SettingValue(types.Bool(), 'false'),
+         "Whether to shrink the completion to be smaller than the configured "
+         "size if there are no scrollbars."),
     )),
 
     ('input', sect.KeyValue(

qutebrowser/widgets/_completion.py

@@ -68,6 +68,7 @@ class CompletionView(QTreeView):
                                arg 1: True if the text should be set
                                       immediately, without continuing
                                       completing the current field.
+        resize_completion: Emitted when the completion should be resized.
     """
 
     STYLESHEET = """
@@ -103,6 +104,7 @@ class CompletionView(QTreeView):
     # FIXME style scrollbar
 
     change_completed_part = pyqtSignal(str, bool)
+    resize_completion = pyqtSignal()
 
     def __init__(self, parent=None):
         super().__init__(parent)
@@ -276,6 +278,9 @@ class CompletionView(QTreeView):
         self._model = model
         self.expandAll()
         self._resize_columns()
+        self._model.rowsRemoved.connect(self.resize_completion)
+        self._model.rowsInserted.connect(self.resize_completion)
+        self.resize_completion.emit()
 
     @pyqtSlot(str, str)
     def on_config_changed(self, section, option):

qutebrowser/widgets/mainwindow.py

@@ -72,10 +72,12 @@ class MainWindow(QWidget):
         self._vbox.addWidget(self.tabs)
 
         self.completion = CompletionView(self)
+        self.completion.resize_completion.connect(self.resize_completion)
 
         self.status = StatusBar()
         self._vbox.addWidget(self.status)
 
+        self.resize_completion()
         #self.retranslateUi(MainWindow)
         #self.tabWidget.setCurrentIndex(0)
         #QtCore.QMetaObject.connectSlotsByName(MainWindow)
@@ -87,17 +89,26 @@ class MainWindow(QWidget):
     @pyqtSlot(str, str)
     def on_config_changed(self, section, option):
         """Resize completion if config changed."""
-        if section == 'completion' and option == 'height':
+        if section == 'completion' and option in ['height', 'shrink']:
             self.resize_completion()
 
+    @pyqtSlot()
     def resize_completion(self):
         """Adjust completion according to config."""
+        # Get the configured height/percentage.
         confheight = str(config.get('completion', 'height'))
         if confheight.endswith('%'):
             perc = int(confheight.rstrip('%'))
             height = self.height() * perc / 100
         else:
             height = int(confheight)
+        # Shrink to content size if needed and shrinking is enabled
+        if config.get('completion', 'shrink'):
+            contents_height = (
+                self.completion.viewportSizeHint().height() +
+                self.completion.horizontalScrollBar().sizeHint().height())
+            if contents_height <= height:
+                height = contents_height
         # hpoint now would be the bottom-left edge of the widget if it was on
         # the top of the main window.
         topleft_y = self.height() - self.status.height() - height