Fix crash when cursor is in an empty script and the user clicks

in the text.

	* src/insets/insetbase.h (notifyCursorLeaves): return a bool
	indicating whether cursor is invalidated.

	* src/mathed/math_nestinset.C (notifyCursorLeaves): 
	* src/mathed/math_hullinset.C (notifyCursorLeaves): adapt to
	prototype change.

	* src/mathed/math_scriptinset.[Ch] (notifyCursorLeaves): return
	true when an inset has been deleted.

	* src/BufferView.C (mouseSetCursor): do not call dEPM when cursor
	is invalidated by notifyCursorLeaves.



git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@14796 a592a061-630c-0410-9148-cb99ea01b6c8

src/BufferView.C

@@ -322,11 +322,13 @@ void BufferView::mouseSetCursor(LCursor & cur)
 	BOOST_ASSERT(&cur.bv() == this);
 
 	// Has the cursor just left the inset?
+	bool badcursor = false;
 	if (&cursor().inset() != &cur.inset())
-		cursor().inset().notifyCursorLeaves(cursor());
+		badcursor = cursor().inset().notifyCursorLeaves(cursor());
 
 	// do the dEPM magic if needed
-	if (cursor().inTexted())
+	// FIXME: move this to InsetText::notifyCursorLeaves?
+	if (!badcursor && cursor().inTexted())
 		cursor().text()->deleteEmptyParagraphMechanism(cur, cursor());
 
 	cursor() = cur;

src/insets/insetbase.h

@@ -170,7 +170,8 @@ public:
 	/// number of columns in gridlike structures
 	virtual size_t ncols() const { return 0; }
 	/// is called when the cursor leaves this inset
-	virtual void notifyCursorLeaves(LCursor &) {}
+	//  returns true if cursor is now invalid.
+	virtual bool notifyCursorLeaves(LCursor &) { return false; }
 
 	/// request "external features"
 	virtual void validate(LaTeXFeatures &) const {}

src/mathed/math_hullinset.C

@@ -386,7 +386,7 @@ void MathHullInset::addPreview(lyx::graphics::PreviewLoader & ploader) const
 }
 
 
-void MathHullInset::notifyCursorLeaves(LCursor & cur)
+bool MathHullInset::notifyCursorLeaves(LCursor & cur)
 {
 	if (RenderPreview::status() == LyXRC::PREVIEW_ON) {
 		Buffer const & buffer = cur.buffer();
@@ -394,6 +394,7 @@ void MathHullInset::notifyCursorLeaves(LCursor & cur)
 		preview_->addPreview(snippet, buffer);
 		preview_->startLoading(buffer);
 	}
+	return false;
 }
 
 

src/mathed/math_hullinset.h

@@ -113,7 +113,7 @@ public:
 		OutputParams const &) const;
 
 	/// get notification when the cursor leaves this inset
-	void notifyCursorLeaves(LCursor & cur);
+	bool notifyCursorLeaves(LCursor & cur);
 	///
 	//bool insetAllowed(Code code) const;
 	///

src/mathed/math_nestinset.C

@@ -350,7 +350,7 @@ int MathNestInset::latex(Buffer const &, std::ostream & os,
 }
 
 
-void MathNestInset::notifyCursorLeaves(LCursor & /*cur*/)
+bool MathNestInset::notifyCursorLeaves(LCursor & /*cur*/)
 {
 #ifdef WITH_WARNINGS
 #warning look here
@@ -379,6 +379,7 @@ void MathNestInset::notifyCursorLeaves(LCursor & /*cur*/)
 		}
 	}
 #endif
+	return false;
 }
 
 

src/mathed/math_nestinset.h

@@ -65,7 +65,7 @@ public:
 	/// access to the lock
 	void lock(bool);
 	/// get notification when the cursor leaves this inset
-	void notifyCursorLeaves(LCursor & cur);
+	bool notifyCursorLeaves(LCursor & cur);
 
 	/// direct access to the cell
 	MathArray & cell(idx_type);

src/mathed/math_scriptinset.C

@@ -555,7 +555,7 @@ void MathScriptInset::infoize2(std::ostream & os) const
 }
 
 
-void MathScriptInset::notifyCursorLeaves(LCursor & cur)
+bool MathScriptInset::notifyCursorLeaves(LCursor & cur)
 {
 	MathNestInset::notifyCursorLeaves(cur);
 
@@ -568,10 +568,12 @@ void MathScriptInset::notifyCursorLeaves(LCursor & cur)
 			// must be a subscript...
 			recordUndoInset(cur);
 			removeScript(false);
+			return true;
 		} else if (cur.idx() == 1 && cell(1).empty()) {
 			// must be a superscript...
 			recordUndoInset(cur);
 			removeScript(true);
+			return true;
 		}
 	} else if (nargs() > 1 && cur.idx() == 1 && cell(1).empty()) {
 		// could be either subscript or super script
@@ -587,9 +589,11 @@ void MathScriptInset::notifyCursorLeaves(LCursor & cur)
 		tmpcur.pop();
 		tmpcur.cell().erase(tmpcur.pos());
 		tmpcur.cell().insert(tmpcur.pos(), ar);
+		return true;
 	}
 
 	//lyxerr << "MathScriptInset::notifyCursorLeaves: 2 " << cur << endl;
+	return false;
 }
 
 

src/mathed/math_scriptinset.h

@@ -121,8 +121,8 @@ private:
 	int ndes() const;
 	/// where do we have to draw the scripts?
 	bool hasLimits() const;
-	/// clean up empty cells
-	void notifyCursorLeaves(LCursor & cur);
+	/// clean up empty cells and return true if a cell has been deleted.
+	bool notifyCursorLeaves(LCursor & cur);
 
 	/// possible subscript (index 0) and superscript (index 1)
 	bool cell_1_is_up_;