From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Mon, 4 Jun 2012 16:02:59 +0000 (+0200)
Subject: Fix bug #8159: Undo doesn't restore environment depth correctly
X-Git-Tag: 2.0.5~135
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=20f128582118777ec3e0bd6b1b3427784d4165b9;p=features.git

Fix bug #8159: Undo doesn't restore environment depth correctly
(backported from master)

The idea is to record undo at the place where the document is modified:

1/ in Buffer::updateBuffer, add a recordUndo, with the caveat that a
   const_cast has to be used (because updateBuffer is const but
   modifies the document, go figure).

2/ in GuiApplication::dispatch, add an extra undo group that
   encompasses the updateBuffer call. Some other undo groups may be
   redundant now, but it is not a problem since they do not cost
   anything.
---

diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index 4f7f4418a4..6560da7343 100644
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -4239,7 +4239,17 @@ void Buffer::updateBuffer(ParIterator & parit, UpdateType utype) const
 	pit_type const lastpit = parit.lastpit();
 	for ( ; parit.pit() <= lastpit ; ++parit.pit()) {
 		// reduce depth if necessary
-		parit->params().depth(min(parit->params().depth(), maxdepth));
+		if (parit->params().depth() > maxdepth) {
+			/** FIXME: this function is const, but
+			 * nevertheless it modifies the buffer. To be
+			 * cleaner, one should modify the buffer in
+			 * another function, which is actually
+			 * non-const. This would however be costly in
+			 * terms of code duplication.
+			 */
+			const_cast<Buffer *>(this)->undo().recordUndo(parit);
+			parit->params().depth(maxdepth);
+		}
 		maxdepth = parit->getMaxDepthAfter();
 
 		if (utype == OutputUpdate) {
diff --git a/src/frontends/qt4/GuiApplication.cpp b/src/frontends/qt4/GuiApplication.cpp
index fe6bf95526..cdf532c29a 100644
--- a/src/frontends/qt4/GuiApplication.cpp
+++ b/src/frontends/qt4/GuiApplication.cpp
@@ -1089,8 +1089,13 @@ static docstring makeDispatchMessage(docstring const & msg,
 
 void GuiApplication::dispatch(FuncRequest const & cmd)
 {
-	if (current_view_ && current_view_->currentBufferView())
+	Buffer * buffer = 0;
+	if (current_view_ && current_view_->currentBufferView()) {
 		current_view_->currentBufferView()->cursor().saveBeforeDispatchPosXY();
+		buffer = &current_view_->currentBufferView()->buffer();
+		if (buffer)
+			buffer->undo().beginUndoGroup();
+	}
 
 	DispatchResult dr;
 	// redraw the screen at the end (first of the two drawing steps).
@@ -1098,6 +1103,10 @@ void GuiApplication::dispatch(FuncRequest const & cmd)
 	dr.screenUpdate(Update::FitCursor);
 	dispatch(cmd, dr);
 	updateCurrentView(cmd, dr);
+
+	// the buffer may have been closed by one action
+	if (theBufferList().isLoaded(buffer))
+		buffer->undo().endUndoGroup();
 }
 
 
diff --git a/status.20x b/status.20x
index def9da3055..304a32972a 100644
--- a/status.20x
+++ b/status.20x
@@ -65,6 +65,8 @@ What's new
 
 - Replace current selection when pasting (bug 8027).
 
+- Make sure that undo restores environment depth correctly (bug 8159).
+
 
 * DOCUMENTATION AND LOCALIZATION