From 31f350693834fb662ba5b8552d530bd2b6b0d076 Mon Sep 17 00:00:00 2001
From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Thu, 17 Aug 2006 21:13:15 +0000
Subject: [PATCH] 	Fix bug 2727.

	* math_scriptinset.C (notifyCursorLeaves): call recordUndoInset
	before deleting a cell; if the nucleus does not have scripts
	anymore, delete it and replace it by its contents at enclosing
	level.
	(write): output scripts even when they are empty.



git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_4_X@14794 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/mathed/ChangeLog          | 10 ++++++++++
 src/mathed/math_scriptinset.C | 20 +++++++++++++++++---
 status.14x                    |  2 ++
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/mathed/ChangeLog b/src/mathed/ChangeLog
index cd2daf5cd4..a9027653c8 100644
--- a/src/mathed/ChangeLog
+++ b/src/mathed/ChangeLog
@@ -1,3 +1,13 @@
+2006-08-17  Jean-Marc Lasgouttes  <lasgouttes@lyx.org>
+
+	Fix bug 2727.
+	
+	* math_scriptinset.C (notifyCursorLeaves): call recordUndoInset
+	before deleting a cell; if the nucleus does not have scripts
+	anymore, delete it and replace it by its contents at enclosing
+	level.
+	(write): output scripts even when they are empty.
+
 2006-08-17  Jean-Marc Lasgouttes  <lasgouttes@lyx.org>
 
 	* math_inset.C (cell): make debug message more explicit.
diff --git a/src/mathed/math_scriptinset.C b/src/mathed/math_scriptinset.C
index f613014bb4..a834c9e3db 100644
--- a/src/mathed/math_scriptinset.C
+++ b/src/mathed/math_scriptinset.C
@@ -19,6 +19,7 @@
 #include "cursor.h"
 #include "debug.h"
 #include "funcrequest.h"
+#include "undo.h"
 
 #include <boost/assert.hpp>
 
@@ -432,10 +433,10 @@ void MathScriptInset::write(WriteStream & os) const
 			os << "{}";
 	}
 
-	if (hasDown() && down().size())
+	if (hasDown() /*&& down().size()*/)
 		os << "_{" << down() << '}';
 
-	if (hasUp() && up().size())
+	if (hasUp() /*&& up().size()*/)
 		os << "^{" << up() << '}';
 
 	if (lock_ && !os.latex())
@@ -563,15 +564,28 @@ void MathScriptInset::notifyCursorLeaves(LCursor & cur)
 		// Case of two scripts. In this case, 1 = super, 2 = sub
 		if (cur.idx() == 2 && cell(2).empty()) {
 			// must be a subscript...
+			recordUndoInset(cur);
 			removeScript(false);
 		} else if (cur.idx() == 1 && cell(1).empty()) {
 			// must be a superscript...
+			recordUndoInset(cur);
 			removeScript(true);
 		}
 	} else if (nargs() > 1 && cur.idx() == 1 && cell(1).empty()) {
 		// could be either subscript or super script
+		recordUndoInset(cur);
 		removeScript(cell_1_is_up_);
-}
+		// Let the script inset commit suicide. This is
+		// modelled on LCursor.pullArg(), but tries not to
+		// invoke notifyCursorLeaves again and does not touch
+		// cur (since the top slice will be deleted
+		// afterwards))
+		MathArray ar = cell(0);
+		LCursor tmpcur = cur;
+		tmpcur.pop();
+		tmpcur.cell().erase(tmpcur.pos());
+		tmpcur.cell().insert(tmpcur.pos(), ar);
+	}
 
 	//lyxerr << "MathScriptInset::notifyCursorLeaves: 2 " << cur << endl;
 }
diff --git a/status.14x b/status.14x
index 7704d577f2..8f7ce57a9c 100644
--- a/status.14x
+++ b/status.14x
@@ -69,6 +69,8 @@ What's new
 
 - Fix lockup when accepting a change in a text inset (bug 2510).
 
+- Fix crash when undoing super/subscript deletion (bug 2727).
+
 - Fix editing of document while Error List dialog is open (bug 2179).
 
 - improve position of cursor after undo.