http://bugzilla.lyx.org/show_bug.cgi?id=2882
The cause of the bug is the following:
When you press backspace in an empty paragraph (which is equivalent to
pressing delete in the lastpos of the paragraph above), LyXText::backspacePos0
just moves the cursor to the left and lets deleteEmptyParagraphMechanism
remove the empty paragraph. However, dEPM does not trigger if the paragraph
isFreeSpacing() and/or allowEmpty(). Both is true for paragraphs in ERT
insets.
There are some tricks to circumvent this for keepEmpty layouts in
LyXText::backspacePos0 (the layout is reset to default), but they do not work
and cannot be expanded for paragraphs in ERT, because isFreeSpacing() and
allowEmpty() always return true if ownerCode == InsetBase::ERT_CODE (see
paragraph.C).
So the best I could come up with is to delete the paragraph manually when we
are in ERT. The attached patch against 1.4 does this and works well AFAICS.
The code for paragraph deletion is basically stolen from dEPM and simplified
as much as I think it could be inside ERT, where there are no Counters and
nested insets to update.
Please review someone, I feel not too confident in the ParagraphList business.
Thanks,
Jürgen
Index: src/text.C
===================================================================
--- src/text.C (Revision 15282)
+++ src/text.C (Arbeitskopie)
@@ -1644,7 +1644,22 @@ bool LyXText::backspacePos0(LCursor & cu
BufferParams const & bparams = buf.params();
par.layout(bparams.getLyXTextClass().defaultLayout());
}
-
+ // Inside ERT insets, we have to delete the par ourselves,
+ // because allowEmpty() and isFreeSpacing() is always true
+ if (par.ownerCode() == InsetBase::ERT_CODE) {
+ LCursor old = cur;
+ cursorLeft(cur);
+ if (cur.pit() == old.pit())
+ return false;
+ // Delete old par.
+ recordUndo(old, Undo::ATOMIC,
+ max(old.pit() - 1, pit_type(0)),
+ min(old.pit() + 1, old.lastpit()));
+ ParagraphList & plist = old.text()->paragraphs();
+ plist.erase(boost::next(plist.begin(), old.pit()));
+ cur.resetAnchor();
+ return true;
+ }
cursorLeft(cur);
return true;
}
