From 5ba1dbb45344f6ef1a5f1bdfebffcd23fbea22e9 Mon Sep 17 00:00:00 2001
From: Enrico Forestieri <forenr@lyx.org>
Date: Mon, 16 Nov 2009 13:59:23 +0000
Subject: [PATCH] Fix bug #6208: macro crash. The fix consists in not updating
 the macro while it is being edited, and this is accomplished by the changes
 in MathData::updateMacros(). However, when clicking away with the mouse I was
 getting another crash, which is cured by the changes in
 MathMacro::notifyCursorLeaves().

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_6_X@32050 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/mathed/MathData.cpp  | 11 +++++++++--
 src/mathed/MathMacro.cpp | 19 ++++++++++---------
 status.16x               |  3 +++
 3 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/src/mathed/MathData.cpp b/src/mathed/MathData.cpp
index f69ae0e840..865e349b4c 100644
--- a/src/mathed/MathData.cpp
+++ b/src/mathed/MathData.cpp
@@ -379,13 +379,20 @@ void MathData::drawT(TextPainter & pain, int x, int y) const
 
 void MathData::updateMacros(Cursor * cur, MacroContext const & mc)
 {
+	// If we are editing a macro, we cannot update it immediately,
+	// as no undo steps will be recorded (bug 6208).
+	InsetMath const * inmath = cur ? cur->inset().asInsetMath() : 0;
+	MathMacro const * inmacro = inmath ? inmath->asMacro() : 0;
+	docstring const edited_name = inmacro ? inmacro->name() : docstring();
+
 	// go over the array and look for macros
 	for (size_t i = 0; i < size(); ++i) {
 		MathMacro * macroInset = operator[](i).nucleus()->asMacro();
 		if (!macroInset || macroInset->name_[0] == '^'
-				|| macroInset->name_[0] == '_')
+				|| macroInset->name_[0] == '_'
+				|| macroInset->name() == edited_name)
 			continue;
-		
+
 		// get macro
 		macroInset->updateMacro(mc);
 		size_t macroNumArgs = 0;
diff --git a/src/mathed/MathMacro.cpp b/src/mathed/MathMacro.cpp
index 875bf9cba2..bccdd8004a 100644
--- a/src/mathed/MathMacro.cpp
+++ b/src/mathed/MathMacro.cpp
@@ -630,15 +630,16 @@ bool MathMacro::notifyCursorLeaves(Cursor const & old, Cursor & cur)
 		docstring const & unfolded_name = name();
 		if (unfolded_name != name_) {
 			// The macro name was changed
-			cur = old;
-			bool left = cur.pos() == 0;
-			cur.recordUndoInset();
-			cur.popForward();
-			cur.backspace();
-			cur.insert(createInsetMath(unfolded_name, &cur.buffer()));
-			if (left)
-				cur.backwardPos();
-			cur.updateFlags(Update::Force);
+			Cursor inset_cursor = old;
+			int macroSlice = inset_cursor.find(this);
+			LASSERT(macroSlice != -1, /**/);
+			inset_cursor.cutOff(macroSlice);
+			inset_cursor.recordUndoInset();
+			inset_cursor.pop();
+			inset_cursor.cell().erase(inset_cursor.pos());
+			inset_cursor.cell().insert(inset_cursor.pos(),
+				createInsetMath(unfolded_name, &cur.buffer()));
+			cur.updateFlags(cur.disp_.update() | Update::SinglePar);
 			return true;
 		}
 	}
diff --git a/status.16x b/status.16x
index 86732abca4..bc4df06056 100644
--- a/status.16x
+++ b/status.16x
@@ -179,6 +179,9 @@ What's new
 - Fix crash when finishing certain math macros such as \frac or font
   changing commands (bug 6110).
 
+- Fix crash when undoing changes to an unknown math macro name such that
+  the macro becomes a known user-defined macro (bug 6208).
+
 - Fix a crash when searching for a string that is found in a table,
   while the cursor is in math (bug 6112).