3 files changed, 24 insertions, 8 deletions
diff --git a/src/Editor.cxx b/src/Editor.cxx
index ee44a6972..caeb9dfdf 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -5644,8 +5644,9 @@ void Editor::ButtonDown(Point pt, unsigned int curTime, bool shift, bool ctrl, b
 				SetDragPosition(SelectionPosition(invalidPosition));
 				if (!shift) {
 					if (ctrl && multipleSelection) {
-						InvalidateSelection(SelectionRange(newPos), true);
-						sel.AddSelection(newPos);
+						SelectionRange range(newPos);
+						sel.TentativeSelection(range);
+						InvalidateSelection(range, true);
 					} else {
 						InvalidateSelection(SelectionRange(newPos), true);
 						if (sel.Count() > 1) 
@@ -5756,8 +5757,7 @@ void Editor::ButtonMove(Point pt) {
 					SetSelection(movePos, sel.RangeMain().anchor);
 				} else if (sel.Count() > 1) {
 					SelectionRange range(movePos, sel.RangeMain().anchor);
-					sel.TrimSelection(range);
-					sel.RangeMain() = range;
+					sel.TentativeSelection(range);
 					InvalidateSelection(range, true);
 				} else {
 					SetSelection(movePos, sel.RangeMain().anchor);
@@ -5883,6 +5883,7 @@ void Editor::ButtonUp(Point pt, unsigned int curTime, bool ctrl) {
 					SetSelection(newPos, sel.RangeMain().anchor);
 				}
 			}
+			sel.CommitTentative();
 		}
 		SetRectangularRange();
 		lastClickTime = curTime;
diff --git a/src/Selection.cxx b/src/Selection.cxx
index 246cfe709..b44d4e96c 100644
--- a/src/Selection.cxx
+++ b/src/Selection.cxx
@@ -156,7 +156,7 @@ void SelectionRange::MinimizeVirtualSpace() {
 	}
 }
 
-Selection::Selection() : mainRange(0), moveExtends(false), selType(selStream) {
+Selection::Selection() : mainRange(0), moveExtends(false), selType(selStream), tentativeMain(false) {
 	AddSelection(SelectionPosition(0));
 }
 
@@ -270,8 +270,19 @@ void Selection::AddSelection(SelectionRange range) {
 	mainRange = ranges.size() - 1;
 }
 
-void Selection::AddSelection(SelectionPosition spPos) {
-	AddSelection(SelectionRange(spPos, spPos));
+void Selection::TentativeSelection(SelectionRange range) {
+	if (!tentativeMain) {
+		rangesSaved = ranges;
+	}
+	ranges = rangesSaved;
+	AddSelection(range);
+	TrimSelection(ranges[mainRange]);
+	tentativeMain = true;
+}
+
+void Selection::CommitTentative() {
+	rangesSaved.clear();
+	tentativeMain = false;
 }
 
 int Selection::CharacterInSelection(int posCharacter) const {
diff --git a/src/Selection.h b/src/Selection.h
index ff13f2130..c18e5c02e 100644
--- a/src/Selection.h
+++ b/src/Selection.h
@@ -123,9 +123,11 @@ struct SelectionRange {
 
 class Selection {
 	std::vector<SelectionRange> ranges;
+	std::vector<SelectionRange> rangesSaved;
 	SelectionRange rangeRectangular;
 	size_t mainRange;
 	bool moveExtends;
+	bool tentativeMain;
 public:
 	enum selTypes { noSel, selStream, selRectangle, selLines, selThin };
 	selTypes selType;
@@ -150,13 +152,15 @@ public:
 	void TrimSelection(SelectionRange range);
 	void SetSelection(SelectionRange range);
 	void AddSelection(SelectionRange range);
-	void AddSelection(SelectionPosition spPos);
+	void TentativeSelection(SelectionRange range);
+	void CommitTentative();
 	int CharacterInSelection(int posCharacter) const;
 	int InSelectionForEOL(int pos) const;
 	int VirtualSpaceFor(int pos) const;
 	void Clear();
 	void RemoveDuplicates();
 	void RotateMain();
+	bool Tentative() const { return tentativeMain; }
 };
 
 #ifdef SCI_NAMESPACE