Editor: clamp coordinates in select(BufferCoord)

src/editor.hh

@@ -62,7 +62,7 @@ public:
     void keep_selection(int index);
     void remove_selection(int index);
     void select(const BufferCoord& c, SelectMode mode = SelectMode::Replace)
-    { select(Selection{ c, c }, mode); }
+    { select(Selection{ buffer().clamp(c) }, mode); }
     void select(const Selection& sel,
                 SelectMode mode = SelectMode::Replace);
     void select(const Selector& selector,

src/selection.hh

@@ -56,6 +56,7 @@ using CaptureList = std::vector<String>;
 // A selection is a Range, associated with a CaptureList
 struct Selection : public Range
 {
+    explicit Selection(const BufferCoord& pos) : Range(pos,pos) {}
     Selection(const BufferCoord& first, const BufferCoord& last,
               CaptureList captures = {})
         : Range(first, last), m_captures(std::move(captures)) {}