Should not automatically generated double barline at end of line where keysig changes next line
On latest git 176a6d7, if I create a keysig within a line (e.g. this F-Major here), then MuseScore correctly does not generate a double barline. However, if I create a keysig at the start of a newline, then musescore generates a double-barline at the end of the previous line: 
I understand that it is common usage to put a double-barline before a keysigature, but that should not be default behavior, because the double-barline signifies the end of a musical section. But not all keysignature changes are significant musical changes, and there is no reason why being at the end of a line should be an inidicator of significance, (especially considering that systemLayout, and not a human, may determine the location of newlines).
| Attachment | Size |
|---|---|
| why-double-barline.mscz | 3.15 KB |
Comments
I also bring this up because I'm investigating #102691: mm-rest toggling somehow converts double-barline into end-start repeat, which I suspect might partially be caused by the auto-generation of double-barlines.
This generated(?) double-barline also results in some inconsistent behavior when switching between page view and continuous view. If I start with:
![start-break-page-view.png]( "start-break-page-view.png")
![start-break-cont-view.png]( "start-break-cont-view.png")
![add-key-sig-cont-view.png]( "add-key-sig-cont-view.png")
![return-page-view-only-single-barline.png]( "return-page-view-only-single-barline.png")
![return-page-re-add-key-sig-produce-double-barline.png]( "return-page-re-add-key-sig-produce-double-barline.png")
![return-cont-after-re-add-key-sig-then-double-barline.png]( "return-cont-after-re-add-key-sig-then-double-barline.png")
if go to continuous view looks like
if add key change in continuous view, then no double barline is generated:
if return to page view, then there is no double barline at the line break! :
but then if re-drop the Fmaj key sig, then I get the double barline! :
Which persists in continuous view:
Things can get even more inconsistent when I don't have a manually-set line break.
Anyway, I do strongly suggest the the behvaior should be: Don't automatically generate double-barlines if keysig occurs on a line break.
Of course if user manually drops a double-barline, then that is fine, and MuseScore should always display that barline as a double barline both in page or continous view.