Merge remote-tracking branch 'origin/pr/3122'

qutebrowser/mainwindow/tabwidget.py

@@ -336,7 +336,7 @@ class TabBar(QTabBar):
         return self.parent().currentWidget()
 
     @pyqtSlot(str)
-    def _on_config_changed(self, option):
+    def _on_config_changed(self, option: str):
         if option == 'fonts.tabs':
             self._set_font()
         elif option == 'tabs.favicons.scale':
@@ -351,6 +351,12 @@ class TabBar(QTabBar):
         if option.startswith('colors.tabs.'):
             self.update()
 
+        # Clear _minimum_tab_size_hint_helper cache when appropriate
+        if option in ["tabs.indicator_padding",
+                      "tabs.padding",
+                      "tabs.width.indicator"]:
+            self._minimum_tab_size_hint_helper.cache_clear()
+
     def _on_show_switching_delay_changed(self):
         """Set timer interval when tabs.show_switching_delay got changed."""
         self._auto_hide_timer.setInterval(config.val.tabs.show_switching_delay)
@@ -459,7 +465,7 @@ class TabBar(QTabBar):
             return
         super().mousePressEvent(e)
 
-    def minimumTabSizeHint(self, index, ellipsis: bool = True):
+    def minimumTabSizeHint(self, index, ellipsis: bool = True) -> QSize:
         """Set the minimum tab size to indicator/icon/... text.
 
         Args:
@@ -469,38 +475,47 @@ class TabBar(QTabBar):
         Return:
             A QSize of the smallest tab size we can make.
         """
-        text = '\u2026' if ellipsis else self.tabText(index)
+        icon = self.tabIcon(index)
+        extent = self.style().pixelMetric(QStyle.PM_TabBarIconSize, None, self)
+        if icon.isNull():
+            icon_width = 0
+        else:
+            icon_width = icon.actualSize(QSize(extent, extent)).width()
+        return self._minimum_tab_size_hint_helper(self.tabText(index),
+                                                  icon_width,
+                                                  ellipsis)
+
+    @functools.lru_cache(maxsize=2**9)
+    def _minimum_tab_size_hint_helper(self, tab_text: str,
+                                      icon_width: int,
+                                      ellipsis: bool) -> QSize:
+        """Helper function to cache tab results.
+
+        Config values accessed in here should be added to _on_config_changed to
+        ensure cache is flushed when needed.
+        """
+        text = '\u2026' if ellipsis else tab_text
         # Don't ever shorten if text is shorter than the ellipsis
         text_width = min(self.fontMetrics().width(text),
-                         self.fontMetrics().width(self.tabText(index)))
-        icon = self.tabIcon(index)
+                         self.fontMetrics().width(tab_text))
         padding = config.val.tabs.padding
         indicator_padding = config.val.tabs.indicator_padding
         padding_h = padding.left + padding.right
         padding_h += indicator_padding.left + indicator_padding.right
         padding_v = padding.top + padding.bottom
-        if icon.isNull():
-            icon_size = QSize(0, 0)
-        else:
-            extent = self.style().pixelMetric(QStyle.PM_TabBarIconSize, None,
-                                              self)
-            icon_size = icon.actualSize(QSize(extent, extent))
         height = self.fontMetrics().height() + padding_v
-        width = (text_width + icon_size.width() +
+        width = (text_width + icon_width +
                  padding_h + config.val.tabs.width.indicator)
         return QSize(width, height)
 
-    def _tab_total_width_pinned(self):
-        """Get the current total width of pinned tabs.
-
-        This width is calculated assuming no shortening due to ellipsis."""
-        return sum(self.minimumTabSizeHint(idx, ellipsis=False).width()
-            for idx in range(self.count())
-            if self._tab_pinned(idx))
-
-    def _pinnedCount(self) -> int:
-        """Get the number of pinned tabs."""
-        return sum(self._tab_pinned(idx) for idx in range(self.count()))
+    def _pinned_statistics(self) -> (int, int):
+        """Get the number of pinned tabs and the total width of pinned tabs."""
+        pinned_list = [idx for idx in range(self.count())
+                       if self._tab_pinned(idx)]
+        pinned_count = len(pinned_list)
+        pinned_width = sum(self.minimumTabSizeHint(idx, ellipsis=False).width()
+                           for idx in pinned_list)
+        return (pinned_count, pinned_width)
 
     def _tab_pinned(self, index: int) -> bool:
         """Return True if tab is pinned."""
@@ -539,8 +554,8 @@ class TabBar(QTabBar):
             return QSize()
         else:
             pinned = self._tab_pinned(index)
-            no_pinned_count = self.count() - self._pinnedCount()
-            pinned_width = self._tab_total_width_pinned()
+            pinned_count, pinned_width = self._pinned_statistics()
+            no_pinned_count = self.count() - pinned_count
             no_pinned_width = self.width() - pinned_width
 
             if pinned:

qutebrowser/misc/utilcmds.py

@@ -182,9 +182,17 @@ def debug_cache_stats():
     except ImportError:
         pass
 
+    tabbed_browser = objreg.get('tabbed-browser', scope='window',
+                                window='last-focused')
+    # pylint: disable=protected-access
+    tab_bar = tabbed_browser.tabBar()
+    tabbed_browser_info = tab_bar._minimum_tab_size_hint_helper.cache_info()
+    # pylint: enable=protected-access
+
     log.misc.debug('is_valid_prefix: {}'.format(prefix_info))
     log.misc.debug('_render_stylesheet: {}'.format(render_stylesheet_info))
     log.misc.debug('history: {}'.format(history_info))
+    log.misc.debug('tab width cache: {}'.format(tabbed_browser_info))
 
 
 @cmdutils.register(debug=True)

tests/unit/mainwindow/test_tabwidget.py

@@ -52,3 +52,16 @@ class TestTabWidget:
 
         with qtbot.waitExposed(widget):
             widget.show()
+
+    def test_update_tab_titles_benchmark(self, benchmark, widget,
+                                         qtbot, fake_web_tab):
+        """Benchmark for update_tab_titles."""
+        widget.addTab(fake_web_tab(), 'foobar')
+        widget.addTab(fake_web_tab(), 'foobar2')
+        widget.addTab(fake_web_tab(), 'foobar3')
+        widget.addTab(fake_web_tab(), 'foobar4')
+
+        with qtbot.waitExposed(widget):
+            widget.show()
+
+        benchmark(widget._update_tab_titles)