Qt: fix display filter completion with few recent entries

If 1) the recent filters menu has less than 10 entries and 2) the cursor
position is not at the end of the filter, then completion would fail.
Additionally, pressing Enter on filters with syntax errors would also
end up being saved, unintentionally.

Fix these by disabling automatic addition of entries by Qt.

Change-Id: I612c6cb8f317beb5459919b5c65b837db6150d07
Reviewed-on: https://code.wireshark.org/review/35150
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Peter Wu <peter@lekensteyn.nl>

1 files changed, 5 insertions, 0 deletions

diff --git a/ui/qt/widgets/display_filter_combo.cpp b/ui/qt/widgets/display_filter_combo.cpp
index d9e9e84ed7..c4d70ba373 100644
--- a/ui/qt/widgets/display_filter_combo.cpp
+++ b/ui/qt/widgets/display_filter_combo.cpp
@@ -35,6 +35,11 @@ DisplayFilterCombo::DisplayFilterCombo(QWidget *parent) :
     // completion for fields handled by DisplayFilterEdit.
     setCompleter(0);
     setLineEdit(new DisplayFilterEdit(this, DisplayFilterToApply));
+    // When the combobox menu is not entirely populated, pressing Enter would
+    // normally append entries to the end. However, before doing so it moves the
+    // cursor position to the end of the field which breaks the completer.
+    // Therefore disable this and rely on dfilter_combo_add_recent being called.
+    setInsertPolicy(QComboBox::NoInsert);
     // Default is Preferred.
     setSizePolicy(QSizePolicy::MinimumExpanding, sizePolicy().verticalPolicy());
     setAccessibleName(tr("Display filter selector"));