Fix bug #11055.

See also https://marc.info/?l=lyx-devel&m=151709211602688&w=2.

(cherry picked from commit d3ee87eea2)

src/Buffer.cpp

@@ -2484,6 +2484,11 @@ void Buffer::makeCitationLabels() const
 }
 
 
+void Buffer::invalidateCiteLabels() const
+{
+	masterBuffer()->d->cite_labels_valid_ = false;
+}
+
 bool Buffer::citeLabelsValid() const
 {
 	return masterBuffer()->d->cite_labels_valid_;

src/Buffer.h

@@ -529,6 +529,8 @@ public:
 	///
 	void makeCitationLabels() const;
 	///
+	void invalidateCiteLabels() const;
+	///
 	bool citeLabelsValid() const;
 	///
 	void getLabelList(std::vector<docstring> &) const;

src/BufferView.cpp

@@ -1357,25 +1357,45 @@ void BufferView::dispatch(FuncRequest const & cmd, DispatchResult & dr)
 		break;
 	}
 
-	case LFUN_UNDO:
+	case LFUN_UNDO: {
 		dr.setMessage(_("Undo"));
 		cur.clearSelection();
+		// We need to find out if the bibliography information
+		// has changed. See bug #11055.
+		// So these should not be references...
+		LayoutModuleList const engines = buffer().params().citeEngine();
+		CiteEngineType const enginetype = buffer().params().citeEngineType();
 		if (!cur.textUndo())
 			dr.setMessage(_("No further undo information"));
-		else
+		else {
 			dr.screenUpdate(Update::Force | Update::FitCursor);
 			dr.forceBufferUpdate();
+			if (buffer().params().citeEngine() != engines ||
+			    buffer().params().citeEngineType() != enginetype)
+				buffer().invalidateCiteLabels();
+		}
 		break;
+	}
 
-	case LFUN_REDO:
+	case LFUN_REDO: {
 		dr.setMessage(_("Redo"));
 		cur.clearSelection();
+		// We need to find out if the bibliography information
+		// has changed. See bug #11055.
+		// So these should not be references...
+		LayoutModuleList const engines = buffer().params().citeEngine();
+		CiteEngineType const enginetype = buffer().params().citeEngineType();
 		if (!cur.textRedo())
 			dr.setMessage(_("No further redo information"));
-		else
+		else {
 			dr.screenUpdate(Update::Force | Update::FitCursor);
 			dr.forceBufferUpdate();
+			if (buffer().params().citeEngine() != engines ||
+			    buffer().params().citeEngineType() != enginetype)
+				buffer().invalidateCiteLabels();
+		}
 		break;
+	}
 
 	case LFUN_FONT_STATE:
 		dr.setMessage(cur.currentState(false));

src/LayoutModuleList.h

@@ -75,6 +75,14 @@ public:
 	/// to be made.
 	bool adaptToBaseClass(LayoutFile const * const lay,
 			std::list<std::string> const & removedModules);
+	///
+	bool operator==(LayoutModuleList const & other) const {
+		return lml_ == other.lml_;
+	}
+	///
+	bool operator!=(LayoutModuleList const & other) const {
+		return !operator==(other);
+	}
 private:
 	/// Removes modules excluded by, provided by, etc, the base class.
 	/// \param lay The document class against which to check.