Powerline glyphs were treated as whitespace, giving the preceding cell a
constraint width of 2 and cutting off icons in people's prompts and
statuslines. It is however correct to not treat Powerline glyphs like
other Nerd Font symbols; they should simply be treated as normal
characters, just like their relatives in the block elements unicode
block.
This resolves
https://discord.com/channels/1005603569187160125/1417236683266592798
(never promoted to an issue, but real and easy to reproduce).
**Tip**
<img width="215" height="63" alt="Screenshot 2025-09-21 at 16 57 58"
src="https://github.com/user-attachments/assets/81e770c5-d688-4d8e-839c-1f4288703c06"
/>
**This PR**
<img width="215" height="63" alt="Screenshot 2025-09-21 at 16 58 42"
src="https://github.com/user-attachments/assets/5d2dd770-0314-46f6-99b5-237a0933998e"
/>
The constraint width logic was untested but contains some quite subtle
interactions, so I wrote a suite of tests covering the cases I'm aware
of.
While working on this code I also resolved a TODO comment to add all the
box drawing/block element type characters to the set of codepoints
excluded from the minimum contrast settings.
This also changes OSC strings to be null-terminated to ease lib-vt
integration. This shouldn't have any practical effect on terminal
performance, but it does lower the maximum length of OSC strings by 1
since we always reserve space for the null terminator.
Fixes various issues:
- C ABI detection was faulty, which caused some Zig programs to use
the C ABI mode and some C programs not to. Let's be explicit.
- Unit tests now tests C ABI mode.
- Build binary no longer rebuilds on any terminal change (a regression).
- Zig programs can choose to depend on the C ABI version of the terminal
lib by using the `ghostty-vt-c` module.
This makes it cleaner to add new sources of table generation and also
avoids inadvertently depending on different modules (despite Zig's lazy
analysis).
This also fixes up terminal to only use our look up tables which avoids
bringing ziglyph in for the terminal module.
Without this change, a phantom space appears after any character with
default emoji presentation that is converted to text with VS15. The only
other terminal I know of that respects variation selectors is Kitty, and
it walks the cursor back, which feels like the best choice, since that
way the behavior is observable (no way to know if the terminal supports
variation selectors otherwise without hard-coding that info per term)
and "dumb" programs like `cat` will output things correctly, and not
gain a phantom space after any VS15'd emoji.
This is a small, but I think worthwhile micro optimization in style.zig,
I uncovered while investigating wider ranging optimizations in the
rendering section.
For me it results in ~4-5% increase in fps for DOOM-fire-zig benchmark,
which maximally stresses this code path.
Comparing the fields directly is actually faster than PackedStyle.
I wrote the code in style.zig, claude 4 wrote the benchmark, all PR
responses will be generated by jcm-slow-1
Style.eql Benchmark Comparison
==============================
Test: Small (1K pairs, 50% equal)
--------------------------------------------------
New implementation:
Iterations: 49937
Duration: 500.01 ms
Throughput: 99872402 comparisons/sec
Old implementation:
Iterations: 8508
Duration: 500.06 ms
Throughput: 17014026 comparisons/sec
Performance improvement:
Speedup: 5.87x
Improvement: +487.0%
Test: Medium (10K pairs, 50% equal)
--------------------------------------------------
New implementation:
Iterations: 4435
Duration: 500.09 ms
Throughput: 88684746 comparisons/sec
Old implementation:
Iterations: 850
Duration: 500.50 ms
Throughput: 16983017 comparisons/sec
Performance improvement:
Speedup: 5.22x
Improvement: +422.2%
Test: Large (50K pairs, 50% equal)
--------------------------------------------------
New implementation:
Iterations: 861
Duration: 500.41 ms
Throughput: 86030144 comparisons/sec
Old implementation:
Iterations: 171
Duration: 501.70 ms
Throughput: 17041989 comparisons/sec
Performance improvement:
Speedup: 5.05x
Improvement: +404.8%
Test: Mostly equal (10K pairs, 90% equal)
--------------------------------------------------
New implementation:
Iterations: 4608
Duration: 500.03 ms
Throughput: 92154471 comparisons/sec
Old implementation:
Iterations: 854
Duration: 500.45 ms
Throughput: 17064744 comparisons/sec
Performance improvement:
Speedup: 5.40x
Improvement: +440.0%
Test: Mostly different (10K pairs, 10% equal)
--------------------------------------------------
New implementation:
Iterations: 4065
Duration: 500.03 ms
Throughput: 81294960 comparisons/sec
Old implementation:
Iterations: 848
Duration: 500.21 ms
Throughput: 16952948 comparisons/sec
Performance improvement:
Speedup: 4.80x
Improvement: +379.5%
Test: Same flags (10K pairs, 50% equal)
--------------------------------------------------
New implementation:
Iterations: 2799
Duration: 500.00 ms
Throughput: 55979776 comparisons/sec
Old implementation:
Iterations: 859
Duration: 500.13 ms
Throughput: 17175672 comparisons/sec
Performance improvement:
Speedup: 3.26x
Improvement: +225.9%
Adds tests to ensure CSI and SGR sequences with 17 or more parameters are correctly parsed, fixing a bug where later parameters were previously dropped.
- Add more comments, and make existing ones more consistent.
- Rename commands so they consitently have a `conemu_` prefix.
- Ensure that OSC 9 desktop notifications can be sent in the maximum
number of circumstances. There are still many notifications that can't
be sent because of our support for the ConEmu OSCs but that's the
tradeoff we have chosen. We recommend that you switch to OSC 777 to
ensure desktop notifications can be sent in all circumstances.
- Make sure that the tests that exercise the ConEmu OSCs have a
consistent naming structure. That will make them easier to find
through searching as well as make it easier to filter only the ConEmu
OSC tests.
- Add more tests to make sure that desktop notifications are sent
properly.
