Line length wrong for background color (unicode)

[peterjc]

Follow on from #872 where the Thai text in http://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-demo.txt
at lines 123-130 seems to render fine - but not necessarily the background coloring.

This seems to be working now in micro 2.0.14 on macOS under WezTerm.

However there is some oddity on the Apple Terminal (testing on macOS 12.7.6) with the background colour on the right hand end of those lines. It is as though the length calculation for drawing the background colour has worked out shorter than the screen width:

This also affects line 57, starting "STARGΛ̊TE SG-1" (TV show Stargate SG-1 with symbolic replacement for A). Here deleting the a-vector and b-vector entries "fixes" it, suggesting the arrow-above modification breaks.

Trying to select the a-vector and b-vector with the mouse is also glitching. For example, a triple click selects the line but appears to only highlight up to half the b-vector. Again, specific to the Apple Terminal, WezTerm was fine.

[peterjc]

There is still possibly a Thai glitch, line 130 (the last line of Thai), column approx 40 (halfway along second column). However I'm not sure how the combined character ought to look - but my terminal rendering vs Firefox differ.

[Andriamanitra]

This might be the same issue as #2925

[peterjc]

Could be - helix definitely breaks on this Thai character: helix-editor/helix#12598

[peterjc]

The background colour highlighting is also broken on the Apple Terminal with macOS Sequoia 15.2. However, it seems to be working micro 2.0.14 on macOS under Ghostty v1.0.1 (and WezTerm on macOS Sequoia).

i.e. The background highlighting could well be an Apple Terminal only glitch, and not a micro bug.

[JoeKar]

This might be the same issue as #2925

Yep, looks like that and I agree that this is more related to micro and his own wide rune processing than different terminals. I assume some terminals hide this symptom.

Do you agree to close it as a duplicate of #2925?