I have noticed you care about `SumTree` (and `Rope`) construction
performance, hence using rayon for parallelism and careful `Chunk`
splitting to avoid reallocation in `Rope::push`. It seemed strange to me
that using multi-threading is that beneficial there, so I tried to
investigate why the serial version (`SumTree::from_iter`) is slow in the
first place.
From my analysis I believe there are two main factors here:
1. `SumTree::from_iter` stores temporary `Node<T>` values in a vector
instead of heap-allocating them immediately and storing `SumTree<T>`
directly, as `SumTree::from_par_iter` does.
2. `Chunk::new` is quite slow: for some reason the compiler does not
vectorize it and seems to struggle to optimize u128 shifts (at least on
x86_64).
For (1) the solution is simple: allocate `Node<T>` immediately after
construction, just like `SumTree::from_par_iter`.
For (2) I was able to get better codegen by rewriting it into a simpler
per-byte loop and splitting computation into smaller chunks to avoid
slow u128 shifts.
There was a similar effort recently in #43193 using portable_simd
(currently nightly only) to optimize `Chunk::push_str`. From what I
understand from that discussion, you seem okay with hand-rolled SIMD for
specific architectures. If so, then I also provide sse2 implementation
for x86_64. Feel free to remove it if you think this is unnecessary.
To test performance I used a big CSV file (~1GB, mostly ASCII) and
measured `Rope::from` with this program:
```rust
fn main() {
let text = std::fs::read_to_string("big.csv").unwrap();
let start = std::time::Instant::now();
let rope = rope::Rope::from(text);
println!("{}ms, {}", start.elapsed().as_millis(), rope.len());
}
```
Here are results on my machine (Ryzen 7 4800H)
| | Parallel | Serial |
| ------------ | -------- | ------ |
| Before | 1123ms | 9154ms |
| After | 497ms | 2081ms |
| After (sse2) | 480ms | 1454ms |
Since serial performance is now much closer to parallel, I also
increased `PARALLEL_THRESHOLD` to 1000. In my tests the parallel version
starts to beat serial at around 150 KB strings. This constant might
require more tweaking and testing though, especially on ARM64.
<details>
<summary>cargo bench (SSE2 vs before)</summary>
```
Running benches\rope_benchmark.rs (D:\zed\target\release\deps\rope_benchmark-3f8476f7dfb79154.exe)
Gnuplot not found, using plotters backend
push/4096 time: [43.592 µs 43.658 µs 43.733 µs]
thrpt: [89.320 MiB/s 89.473 MiB/s 89.610 MiB/s]
change:
time: [-78.523% -78.222% -77.854%] (p = 0.00 < 0.05)
thrpt: [+351.56% +359.19% +365.61%]
Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
1 (1.00%) high mild
1 (1.00%) high severe
push/65536 time: [632.36 µs 634.03 µs 635.76 µs]
thrpt: [98.308 MiB/s 98.576 MiB/s 98.836 MiB/s]
change:
time: [-51.521% -50.850% -50.325%] (p = 0.00 < 0.05)
thrpt: [+101.31% +103.46% +106.28%]
Performance has improved.
Found 18 outliers among 100 measurements (18.00%)
11 (11.00%) low mild
6 (6.00%) high mild
1 (1.00%) high severe
append/4096 time: [11.635 µs 11.664 µs 11.698 µs]
thrpt: [333.92 MiB/s 334.89 MiB/s 335.72 MiB/s]
change:
time: [-24.543% -23.925% -22.660%] (p = 0.00 < 0.05)
thrpt: [+29.298% +31.450% +32.525%]
Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
2 (2.00%) low mild
2 (2.00%) high mild
8 (8.00%) high severe
append/65536 time: [1.1287 µs 1.1324 µs 1.1360 µs]
thrpt: [53.727 GiB/s 53.900 GiB/s 54.075 GiB/s]
change:
time: [-44.153% -37.614% -29.834%] (p = 0.00 < 0.05)
thrpt: [+42.518% +60.292% +79.061%]
Performance has improved.
slice/4096 time: [28.340 µs 28.372 µs 28.406 µs]
thrpt: [137.52 MiB/s 137.68 MiB/s 137.83 MiB/s]
change:
time: [-8.0798% -6.3955% -4.4109%] (p = 0.00 < 0.05)
thrpt: [+4.6145% +6.8325% +8.7900%]
Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
1 (1.00%) low mild
1 (1.00%) high mild
1 (1.00%) high severe
slice/65536 time: [527.51 µs 528.17 µs 528.90 µs]
thrpt: [118.17 MiB/s 118.33 MiB/s 118.48 MiB/s]
change:
time: [-53.819% -45.431% -34.578%] (p = 0.00 < 0.05)
thrpt: [+52.853% +83.256% +116.54%]
Performance has improved.
Found 5 outliers among 100 measurements (5.00%)
1 (1.00%) low severe
3 (3.00%) low mild
1 (1.00%) high mild
bytes_in_range/4096 time: [3.2545 µs 3.2646 µs 3.2797 µs]
thrpt: [1.1631 GiB/s 1.1685 GiB/s 1.1721 GiB/s]
change:
time: [-3.4829% -2.4391% -1.7166%] (p = 0.00 < 0.05)
thrpt: [+1.7466% +2.5001% +3.6085%]
Performance has improved.
Found 8 outliers among 100 measurements (8.00%)
6 (6.00%) high mild
2 (2.00%) high severe
bytes_in_range/65536 time: [80.770 µs 80.832 µs 80.904 µs]
thrpt: [772.52 MiB/s 773.21 MiB/s 773.80 MiB/s]
change:
time: [-1.8710% -1.3843% -0.9044%] (p = 0.00 < 0.05)
thrpt: [+0.9126% +1.4037% +1.9067%]
Change within noise threshold.
Found 8 outliers among 100 measurements (8.00%)
5 (5.00%) high mild
3 (3.00%) high severe
chars/4096 time: [790.50 ns 791.10 ns 791.88 ns]
thrpt: [4.8173 GiB/s 4.8220 GiB/s 4.8257 GiB/s]
change:
time: [+0.4318% +1.4558% +2.0256%] (p = 0.00 < 0.05)
thrpt: [-1.9854% -1.4349% -0.4299%]
Change within noise threshold.
Found 6 outliers among 100 measurements (6.00%)
1 (1.00%) low severe
1 (1.00%) low mild
2 (2.00%) high mild
2 (2.00%) high severe
chars/65536 time: [12.672 µs 12.688 µs 12.703 µs]
thrpt: [4.8046 GiB/s 4.8106 GiB/s 4.8164 GiB/s]
change:
time: [-2.7794% -1.2987% -0.2020%] (p = 0.04 < 0.05)
thrpt: [+0.2025% +1.3158% +2.8588%]
Change within noise threshold.
Found 15 outliers among 100 measurements (15.00%)
1 (1.00%) low mild
12 (12.00%) high mild
2 (2.00%) high severe
clip_point/4096 time: [63.009 µs 63.126 µs 63.225 µs]
thrpt: [61.783 MiB/s 61.880 MiB/s 61.995 MiB/s]
change:
time: [+2.0484% +3.2218% +5.2181%] (p = 0.00 < 0.05)
thrpt: [-4.9593% -3.1213% -2.0073%]
Performance has regressed.
Found 13 outliers among 100 measurements (13.00%)
12 (12.00%) low mild
1 (1.00%) high severe
Benchmarking clip_point/65536: Warming up for 3.0000 s
Warning: Unable to complete 100 samples in 5.0s. You may wish to increase target time to 7.7s, enable flat sampling, or reduce sample count to 50.
clip_point/65536 time: [1.2420 ms 1.2430 ms 1.2439 ms]
thrpt: [50.246 MiB/s 50.283 MiB/s 50.322 MiB/s]
change:
time: [-0.3495% -0.0401% +0.1990%] (p = 0.80 > 0.05)
thrpt: [-0.1986% +0.0401% +0.3507%]
No change in performance detected.
Found 7 outliers among 100 measurements (7.00%)
6 (6.00%) high mild
1 (1.00%) high severe
point_to_offset/4096 time: [16.104 µs 16.119 µs 16.134 µs]
thrpt: [242.11 MiB/s 242.33 MiB/s 242.56 MiB/s]
change:
time: [-1.3816% -0.2497% +2.2181%] (p = 0.84 > 0.05)
thrpt: [-2.1699% +0.2503% +1.4009%]
No change in performance detected.
Found 6 outliers among 100 measurements (6.00%)
3 (3.00%) low mild
1 (1.00%) high mild
2 (2.00%) high severe
point_to_offset/65536 time: [356.28 µs 356.57 µs 356.86 µs]
thrpt: [175.14 MiB/s 175.28 MiB/s 175.42 MiB/s]
change:
time: [-3.7072% -2.3338% -1.4742%] (p = 0.00 < 0.05)
thrpt: [+1.4962% +2.3896% +3.8499%]
Performance has improved.
Found 1 outliers among 100 measurements (1.00%)
1 (1.00%) low mild
cursor/4096 time: [18.893 µs 18.934 µs 18.974 µs]
thrpt: [205.87 MiB/s 206.31 MiB/s 206.76 MiB/s]
change:
time: [-2.3645% -2.0729% -1.7931%] (p = 0.00 < 0.05)
thrpt: [+1.8259% +2.1168% +2.4218%]
Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
12 (12.00%) high mild
cursor/65536 time: [459.97 µs 460.40 µs 461.04 µs]
thrpt: [135.56 MiB/s 135.75 MiB/s 135.88 MiB/s]
change:
time: [-5.7445% -4.2758% -3.1344%] (p = 0.00 < 0.05)
thrpt: [+3.2358% +4.4668% +6.0946%]
Performance has improved.
Found 2 outliers among 100 measurements (2.00%)
1 (1.00%) high mild
1 (1.00%) high severe
append many/small to large
time: [38.364 ms 38.620 ms 38.907 ms]
thrpt: [313.75 MiB/s 316.08 MiB/s 318.19 MiB/s]
change:
time: [-0.2042% +1.0954% +2.3334%] (p = 0.10 > 0.05)
thrpt: [-2.2802% -1.0836% +0.2046%]
No change in performance detected.
Found 21 outliers among 100 measurements (21.00%)
9 (9.00%) high mild
12 (12.00%) high severe
append many/large to small
time: [48.045 ms 48.322 ms 48.648 ms]
thrpt: [250.92 MiB/s 252.62 MiB/s 254.07 MiB/s]
change:
time: [-6.5298% -5.6919% -4.8532%] (p = 0.00 < 0.05)
thrpt: [+5.1007% +6.0354% +6.9859%]
Performance has improved.
Found 11 outliers among 100 measurements (11.00%)
2 (2.00%) high mild
9 (9.00%) high severe
```
</details>
Release Notes:
- N/A *or* Added/Fixed/Improved ...
## Fix incorrect directory path folding in slash command file collection
**Description:**
This PR fixes a bug in the `collect_files` function where the directory
folding logic (used to compact chains like `.github/workflows`) failed
to reset its state when traversing out of a folded branch.
**The Issue:**
The `folded_directory_names` accumulator was persisting across loop
iterations. If the traversal moved from a folded directory (e.g.,
`.github/workflows`) to a sibling directory (e.g., `.zed`), the sibling
would incorrectly inherit the prefix of the previously folded path,
resulting in incorrect paths like `.github/.zed`.
**The Fix:**
* Introduced `folded_directory_path` to track the specific path
currently being folded.
* Added a check to reset `folded_directory_names` whenever the traversal
encounters an entry that is not a child of the currently folded path.
* Ensured state is cleared immediately after a folded directory is
rendered.
**Release Notes:**
- Fixed an issue where using slash commands to collect files would
sometimes display incorrect directory paths (e.g., showing
`.github/.zed` instead of `.zed`) when adjacent directories were
automatically folded.
---------
Co-authored-by: Lukas Wirth <lukas@zed.dev>
### Summary:
- Ensure the external agents with ACP servers start via non-interactive
shells to prevent shell startup noise from corrupting JSON-RPC.
- Apply the same tweak to MCP stdio transports so remote context servers
aren’t affected by prompts or greetings.
### Description:
Switch both ACP and MCP stdio launch paths to call
`ShellBuilder::non_interactive()` before building the command. This
removes `-i` on POSIX shells, suppressing prompt/title sequences that
previously prefixed the first JSON line and caused `serde_json` parse
failures. No functional regressions are expected: both code paths only
need a shell for Windows/npm script compatibility, not for
interactivity.
Release Notes:
- Fixed external agents that hung on “Loading…” when shell startup
output broke JSON-RPC initialization.
Zed currently doesn’t support all protocol extensions implemented by
`clangd`, but it does support two:
- `textDocument/inactiveRegion`
- `textDocument/switchSourceHeader`
Release Notes:
- N/A
---------
Co-authored-by: Kunall Banerjee <hey@kimchiii.space>
Fixes#33958
## Problem
When opening a terminal in Zed, `SHLVL` incorrectly starts at 2 instead
of 1. On `workspace: reload`, it increases by 2 instead of 1.
## Root Cause
1. Zed's `shell_env::capture()` spawns a login shell (`-l -i -c`) to
capture the user's environment, which increments `SHLVL`
2. The captured `SHLVL` is passed through to the PTY options
3. When alacritty_terminal spawns the user's shell, it increments
`SHLVL` again
Result: `SHLVL` = captured value + 1 = 2 (when launched from Finder)
## Solution
Remove `SHLVL` from the environment in `TerminalBuilder::new()` before
passing it to alacritty_terminal. This allows the spawned shell to
initialize `SHLVL` to 1 on its own, matching the behavior of standalone
terminal emulators like iTerm2, Kitty, and Alacritty.
## Testing
- Launch Zed from Finder → open terminal → `echo $SHLVL` → should output
`1`
- Launch Zed from shell → open terminal → `echo $SHLVL` → should output
`1`
- `workspace: reload` → open terminal → `echo $SHLVL` → should remain
`1`
- Tested with bash, zsh, fish
Release Notes:
- Fixed terminal `$SHLVL` starting at 2 instead of 1
([#33958](https://github.com/zed-industries/zed/issues/33958))
This PR adds a staff-only button to the edit prediction menu for
capturing your current editing session as edit prediction example file.
When you click that button, it opens a markdown tab with the example. By
default, the most recent change that you've made is used as the expected
patch, and all of the previous events are used as the editing history.
<img width="303" height="123" alt="Screenshot 2025-12-14 at 6 58 33 PM"
src="https://github.com/user-attachments/assets/600c7bf2-7cf4-4d27-8cd4-8bb70d0b20b0"
/>
Release Notes:
- N/A
Imitating the approach of #41829. Prevents e.g. reverting a hunk and
having that excerpt yanked out from under the cursor.
Release Notes:
- git: Improved stability of excerpts when editing in the project diff.
The test `test_collaborating_with_completion` has a latent race
condition that hasn't manifested on CI yet but could cause hangs with
certain task orderings.
## The Bug
Commit `fd1494c31a` set up LSP request handlers AFTER typing the trigger
character:
```rust
// Type trigger first - spawns async tasks to send completion request
editor_b.update_in(cx_b, |editor, window, cx| {
editor.handle_input(".", window, cx);
});
// THEN set up handlers (race condition!)
fake_language_server
.set_request_handler::<lsp::request::Completion, _, _>(...)
.next().await.unwrap(); // Waits for handler to receive a request
```
Whether this works depends on task scheduling order, which varies by
seed. If the completion request is processed before the handler is
registered, the request goes to `on_unhandled_notification` which claims
to handle it but sends no response, causing a hang.
## Changes
- Move handler setup BEFORE typing the trigger character
- Make `TestDispatcher::spawn_realtime` panic to prevent future
non-determinism from real OS threads
- Add `execution_hash()` and `execution_count()` to TestDispatcher for
debugging
- Add `DEBUG_SCHEDULER=1` logging for task execution tracing
- Document the investigation in `situation.md`
cc @localcc @SomeoneToIgnore (authors of related commits)
Release Notes:
- N/A
---------
Co-authored-by: Kirill Bulatov <kirill@zed.dev>
This adds implementations of `std::iter::Sum` for `Pixels`, allowing the
use of `.sum()` on iterators of `Pixels` values.
### Changes
- Implement `Sum<Pixels>` for `Pixels` (owned values)
- Implement `Sum<&Pixels>` for `Pixels` (references)
This enables ergonomic patterns like:
```rust
let total: Pixels = pixel_values.iter().sum();
```
This change matches how normal hovers are handled (which early return
with `None` in this branch)
Release Notes:
- Fixed hover boxes for inlays blinking in and out without movement when
cursor blinking was enabled
When an external agent doesn't provide an icon, we were using different
fallback icons in all the places we display icons (settings view, thread
new menu, and the thread view toolbar itself).
Release Notes:
- N/A
Fix a bug where the branch picker would be dismissed before completing
the add remote flow, thus making Zed unable to add remote repositories
through the branch picker.
This bug was caused by the picker always being dismissed on the confirm
action, so the fix was stopping the branch modal from being dismissed
too early.
I also cleaned up the UI a bit and code.
1. Removed the loading field from the Branch delegate because it was
never used and the activity indicator will show remote add command if it
takes a while.
2. I replaced some async task spawning with the use of `cx.defer`.
3. Added a `add remote name` fake entry when the picker is in the name
remote state. I did this so the UI would be consistent with the other
states.
4. Added two regression tests.
4.1 One to prevent this bug from occurring again:
https://github.com/zed-industries/zed/pull/44742
4.2 Another to prevent the early dismissal bug from occurring
5. Made `init_branch_list_test` param order consistent with Zed's code
base
###### Updated UI
<img width="1150" height="298" alt="image"
src="https://github.com/user-attachments/assets/edead508-381c-4bd8-8a41-394dd5b7b781"
/>
Release Notes:
- N/A
Add the repository name when:
- there's more than one repository, and
- the name of the active repository doesn't match the name of the
project (to avoid stuttering with the adjacent project switcher button)
Release Notes:
- The branch name in the title bar now includes the name of the current
repository when needed to disambiguate.
- Edit prediction providers can now be configured through the settings
UI
- Cleaned up the status bar menu to only show _configured_ providers
- Added to the status bar icon button tooltip the name of the active
provider
- Only display the data collection functionality under "Privacy" for the
Zed models
- Moved the Codestral edit prediction provider out of the Mistral
section in the agent panel into the settings UI
- Refined and improved UI and states for configuring GitHub Copilot as
both an agent and edit prediction provider
#### Todos before merge:
- [x] UI: Unify with settings UI style and tidy it all up
- [x] Unify Copilot modal `impl`s to use separate window
- [x] Remove stop light icons from GitHub modal
- [x] Make dismiss events work on GitHub modal
- [ ] Investigate workarounds to tell if Copilot authenticated even when
LSP not running
Release Notes:
- settings_ui: Added a section for configuring edit prediction providers
under AI > Edit Predictions, including Codestral and GitHub Copilot.
Once you've updated you can use the following link to open it:
zed://settings/edit_predictions.providers
---------
Co-authored-by: Ben Kunkle <ben@zed.dev>
This fixes an issue where a user could get confused by the branch picker
because it would only show the 10 most recent branches, instead of all
branches.
Release Notes:
- git: Show all branches in branch picker when search field is empty
We were panicking whenever something went wrong with an example in the
CLI. This can be very disruptive when running many examples, and e.g a
single request fails. Instead, if running more than one example, errors
will now be logged alongside instructions to explore and re-run the
example by itself.
<img width="1454" height="744" alt="CleanShot 2025-12-12 at 13 32 04@2x"
src="https://github.com/user-attachments/assets/87c59e64-08b9-4461-af5b-03af5de94152"></img>
You can still opt in to stop as soon as en error occurs with the new
`--failfast` argument.
Release Notes:
- N/A
Improves the scheduler by allowing tasks to have a set priority which
will significantly improve responsiveness.
Release notes:
- N/A
---------
Co-authored-by: Yara <git@yara.blue>
Co-authored-by: dvdsk <noreply@davidsk.dev>
- Limit status lines to 10 in case `max_parallelism` is specified with a
grater value
- Handle logging gracefully rather than writing over it when clearing
status lines
Release Notes:
- N/A
Currently we have a single cache for this data shared between all
snapshots which is incorrect, as we might update the cache to a new
version while having old snapshots around which then may try to access
new data with old offsets/rows.
Release Notes:
- N/A *or* Added/Fixed/Improved ...
Update the issue template used for "Report a bug" to include a field
specifically for the user's keymap file, as we've seen multiple cases
where we end up asking the users for their custom keymap, to ensure that
they're not overriding existing defaults.
Release Notes:
- N/A
- Fix missing font features in
`git_ui::blame_ui::GitBlameRenderer.render_blame_entry`
- Fix missing buffer font features in
`markdown_preview::markdown_renderer`
- Update the way that the markdown style is built for hover popovers so
that, for code blocks, the buffer font features are used.
- Introduce `gpui::Styled.font_features` to allow callers to also set
the font's features, similar to how `gpui::Styled.font_family` already
exists.
Relates to #44209
Release Notes:
- Fixed wrong font features in Blame UI, Hover Popover and Markdown
Preview
Closes#41567
We were using the git panel editor to check the focus where the commit
modal has its only editor.
Release Notes:
- Fixed an issue where commit and amend actions wouldn’t trigger when
using keybinds in the commit modal.
Update the behavior of `git::Amend` to ensure that the latest head
commit message, if available, is always loaded into the commit message
editor, regardless of its state. The previous text, if any, is now also
restored after the amend is finished.
- Update `FakeGitRepository.show` to include a message in the returned
`CommitDetails` so we can assert that this specific commit message is
set in the commit message editor.
- Add default implementation for `FakeGitRepository.commit` and
`FakeGitRepository.run_hook` to ensure that tests are able to run and
don't panic on `unimplemented!()`
- Refactor `GitPanel.load_last_commit_message_if_empty` to
`GitPanel.load_last_commit_message`, ensuring that the head commit
message is always loaded, regardless of whether the commit message
editor is empty.
- Update `GitPanel.commit_changes` to ensure that the pending amend
state is only updated if the editor managed to actually commit the
changes. This also ensures that we don't restore the commit message
editor's contents when amending a commit, before the amend is actually
processed.
- Update `CommitModal.amend`, removing the call to
`GitPanel.set_amend_pending` as that is now handled by the background
task created in `GitPanel.commit_changes`.
- Split the `commit` and `amend` methods from the event handlers so that
the methods can be called directly, as is now being done by
`CommitModal.on_commit` and `CommitModal.on_amend`.
Release Notes:
- Updated the `git: amend` command to always load the latest head
commit message, and to restore any previously entered text in the commit
message editor after the amend completes
