[LyX/master] Revert "Allow to undo partly math autocorrect"

[Jean-Marc Lasgouttes]

commit 8e3972c35d302e1988605940cac6f6a8e9e66ce0
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Tue Apr 16 16:03:57 2019 +0200

    Revert "Allow to undo partly math autocorrect"
    
    This reverts commit f7a11ca7115064710b98bedc64d724ca15362527.
---
 src/Cursor.cpp                 |    6 ------
 src/Cursor.h                   |    2 --
 src/Undo.cpp                   |   10 ----------
 src/Undo.h                     |    2 --
 src/mathed/MathAutoCorrect.cpp |   13 ++-----------
 5 files changed, 2 insertions(+), 31 deletions(-)

diff --git a/src/Cursor.cpp b/src/Cursor.cpp
index 735ee34..56a9dd8 100644
--- a/src/Cursor.cpp
+++ b/src/Cursor.cpp
@@ -607,12 +607,6 @@ void CursorData::endUndoGroup() const
 }
 
 
-void CursorData::splitUndoGroup() const
-{
-       buffer()->undo().splitUndoGroup(*this);
-}
-
-
 void CursorData::recordUndo(pit_type from, pit_type to) const
 {
        buffer()->undo().recordUndo(*this, from, to);
diff --git a/src/Cursor.h b/src/Cursor.h
index 3d3db5d..38ddad3 100644
--- a/src/Cursor.h
+++ b/src/Cursor.h
@@ -183,8 +183,6 @@ public:
        void beginUndoGroup() const;
        /// end the current undo group
        void endUndoGroup() const;
-       /// end abruptly the current group and create a new one wih the same 
nesting level
-       void splitUndoGroup() const;
 
        /// The general case: prepare undo for an arbitrary range.
        void recordUndo(pit_type from, pit_type to) const;
diff --git a/src/Undo.cpp b/src/Undo.cpp
index a9e0bba..5d613f2 100644
--- a/src/Undo.cpp
+++ b/src/Undo.cpp
@@ -610,16 +610,6 @@ void Undo::endUndoGroup(CursorData const & cur_after)
 }
 
 
-void Undo::splitUndoGroup(CursorData const & cur)
-{
-       size_t const level = d->group_level_;
-       d->group_level_ = 1;
-       endUndoGroup(cur);
-       beginUndoGroup(cur);
-       d->group_level_ = level;
-}
-
-
 bool Undo::activeUndoGroup() const
 {
        return d->group_level_ > 0
diff --git a/src/Undo.h b/src/Undo.h
index c2b9b5d..dd70358 100644
--- a/src/Undo.h
+++ b/src/Undo.h
@@ -96,8 +96,6 @@ public:
        void endUndoGroup();
        /// end the current undo group and set UndoElement::cur_after if 
necessary.
        void endUndoGroup(CursorData const & cur_after);
-       /// end abruptly the current group and create a new one wih the same 
nesting level
-       void splitUndoGroup(CursorData const & cur);
        /// return true if an undo group is open and contains at least one 
element
        bool activeUndoGroup() const;
 
diff --git a/src/mathed/MathAutoCorrect.cpp b/src/mathed/MathAutoCorrect.cpp
index 77e5fef..be5aeb4 100644
--- a/src/mathed/MathAutoCorrect.cpp
+++ b/src/mathed/MathAutoCorrect.cpp
@@ -90,17 +90,8 @@ bool Correction::correct(Cursor & cur, char_type c) const
        LYXERR(Debug::MATHED, "match found! subst in " << cur.cell()
                << " from: '" << from1_ << "' to '" << to_ << '\'');
 
-       /* To allow undoing the completion, we proceed in 4 steps
-        * - inset the raw character
-        * - split undo group so that we have two separate undo actions
-        * - record undo, delete the character we just entered and the from1_ 
part
-        * - finally, do the insertion of the correction.
-        */
-       cur.insert(c);
-       cur.splitUndoGroup();
-       cur.recordUndoSelection();
-       cur.cell().erase(cur.pos() - n - 1, cur.pos());
-       cur.pos() -= n + 1;
+       cur.cell().erase(cur.pos() - n, cur.pos());
+       cur.pos() -= n;
 
        cur.insert(to_);
        return true;