* Set an index for the last saved change
I added an index that represents the last saved change.
Editors are considered to be unsaved or modified if the current change
is different from the save index. In other words, if the last saved
change is `5`, undoing or redoing past that change should indicate that
the editor has been modified.
This is needed to fix two bugs in COSMIC Edit:
* https://github.com/pop-os/cosmic-edit/issues/116
* https://github.com/pop-os/cosmic-edit/issues/128
* Unit test that confirms pivot logic works
I'll most likely simplify the API as end users don't have a way to
cleanly use `Pivot::Exact` without access to the internal command
buffer.
* Simplify save point API
* Implement more save point unit tests
A unit test for an edge case currently fails but normal usage works.
* Fix edge case for empty command index and pivot
* More save point unit tests for common use cases
Instead of blindly pushing default font to the start of the monospace
fallbacks map. Actually collect codepoint support info for it, and if
it supports all codepoints, skip collecting that info from other
monospace fonts. If it doesn't, push it to the start of the map as
before.
This actually provides a big performance boost, while the sophisticated
monospace fallback process is still done whenever needed.
Signed-off-by: Mohammad AlSaleh <CE.Mohammad.AlSaleh@gmail.com>
When font fallback involves monospace fonts, and if word has known
scripts, limit the fonts tried for fallback to ones that support at
least one requested script.
Codepoint support info is still collected for these fonts to guide
the fallback order selection process.
A map of per-script monospace font-ids is pre-populated in font system
to acquire lists of wanted font ids efficiently.
Signed-off-by: Mohammad AlSaleh <CE.Mohammad.AlSaleh@gmail.com>
