ratatui-v0.30.2

![a gift](https://github.com/ratatui/ratatui-website/raw/refs/heads/main/src/assets/a-gift.png)

We are excited to announce the new version of `ratatui` - a Rust library that's all about cooking up TUIs 👨‍🍳🐀

✨ **Release highlights**: <https://ratatui.rs/highlights/v0302/>

⚠️ List of breaking changes can be found [here](https://github.com/ratatui/ratatui/blob/main/BREAKING-CHANGES.md).

### Features

- [90639c1](https://github.com/ratatui/ratatui/commit/90639c179ddcbe483ea05f21b1ce3fa09767441a) *(uncategorized)* Add Termina backend by `@joshka` in [#2561](https://github.com/ratatui/ratatui/pull/2561)

  > ## Summary
  >
  > - add the `ratatui-termina` backend crate using the published `termina`
  > crate
  > - expose the backend through the `termina` feature and Ratatui
  > prelude/backend re-exports
  > - add a small Termina event-loop example and wire the backend into CI,
  > xtask, README generation, and docs
  >
  > Refs #1784
  >
  > ## Validation
  >
  > - `cargo +nightly fmt`
  > - `cargo check -p ratatui-termina --all-features --all-targets`
  > - `cargo check -p ratatui --no-default-features --features termina`
  > - `cargo check -p xtask`
  > - `cargo check -p release-header`
  > - `cargo xtask check-backend termina`
  > - `cargo xtask test-backend termina`
  > - `cargo xtask rdme --check`
  > - `markdownlint-cli2 ARCHITECTURE.md ratatui-termina/README.md
  > .github/ISSUE_TEMPLATE/bug_report.md`
  >
  > ---------

### Bug Fixes

- [fce3c80](https://github.com/ratatui/ratatui/commit/fce3c80d53d5cf367e62cadf1d5c819947d23e4c) *(widgets)* Require thread-safe shadow effects by `@joshka` in [#2584](https://github.com/ratatui/ratatui/pull/2584)

  > ## Summary
  >
  > - require custom shadow effects to preserve the auto traits expected by
  > Block-backed widgets
  > - document the CellEffect auto-trait contract
  > - add a public widget regression test for the affected ratatui::widgets
  > re-exports
  >
  > Fixes #2583
  >
  > ---------

- [e306ce6](https://github.com/ratatui/ratatui/commit/e306ce69df3113d41c00c483e36ba3ecc88f3c79) *(buffer)* Create updates for "uncovered" cells by `@benjajaja` in [#2587](https://github.com/ratatui/ratatui/pull/2587)

  > When a wide cell from the previous buffer is replaced by a short/normal
  > cell, the trailing cell does not get an update if its content does not
  > change. But if the wide cell has a background (or other) style, the
  > terminal *did* render the trailing cell with that style.
  >
  > Force trailing cells to update if background, underline, or modifiers
  > are different than the wide cell. We can ignore foreground.
  >
  > Fixes #2585 (see that for the detailed visual reports)

- [81e667f](https://github.com/ratatui/ratatui/commit/81e667f354489a809e0db1f95e378efe859dd409) *(scrollbar)* Keep a large thumb within the track at the end by `@satyakwok` in [#2594](https://github.com/ratatui/ratatui/pull/2594)
  >
  > Closes #2582.
  >
  > ## Problem
  >
  > When the content is shorter than the viewport, the thumb is large
  > relative to the track. With the position at the end, `part_lengths`
  > clamped `thumb_start` to `track_length - 1` while `thumb_length` was
  > clamped independently to `[1, track_length]`, so `thumb_start +
  > thumb_length` could exceed `track_length`.
  >
  > `bar_symbols` lays out `begin + track_start + thumb + track_end + end`
  > and zips it against the cells of the area. When the thumb overruns the
  > track, `track_end` saturates to `0` but the thumb still emits more cells
  > than the track can hold, so the trailing `end` symbol is pushed past the
  > end of the area. The last visible cell ends up being a thumb (`█`) where
  > the end arrow (`▼`) should be.
  >
  > Concretely, for the issue's repro (`VerticalRight`, `content_length =
  > 9`, `position = 8`, height `24`): track is `22`, `thumb_length = 17`,
  > `thumb_start = 6`, and `6 + 17 = 23 > 22`.
  >
  > This is a regression from v0.30.0, where `thumb_length` was derived as
  > `thumb_end - thumb_start` and therefore always fit within the track.
  >
  > ## Fix
  >
  > Clamp `thumb_start` to `track_length - thumb_length` (instead of
  > `track_length - 1`) so the thumb always fits within the track and the
  > end symbol is preserved.
  >
  > ## Test
  >
  > Two regression tests, both fail on `main` and pass with the fix:
  >
  > - `thumb_stays_within_track_for_large_thumb_at_end` checks
  > `part_lengths` directly with the issue's parameters — asserts
  > `thumb_start + thumb_length <= track_length` and that the parts sum to
  > the track length.
  > - `render_scrollbar_keeps_end_symbol_for_large_thumb` renders the #2582
  > case (both arrows, large thumb at the end) and asserts the end symbol is
  > drawn rather than overwritten by a thumb cell.
  >
  > All existing scrollbar tests still pass.


### Miscellaneous Tasks

- [c75d778](https://github.com/ratatui/ratatui/commit/c75d7782be5c8157b0c140821090a13fd8cb8eb0) *(ci)* Add cargo-udeps dependency check by `@joshka` in [#2599](https://github.com/ratatui/ratatui/pull/2599)

  > Adds cargo xtask udeps and runs it from CI as a required job.
  >
  > This complements cargo-machete rather than replacing it. cargo-machete
  > is a fast static source scan, which is why it missed the package-level
  > unused deps fixed in #2598 when the same dependency names were still
  > referenced by example crates. cargo-udeps compiles the workspace and
  > checks rustc dep-info, so it can catch unused dependency declarations
  > for the package being checked.
  >
  > To make the new job pass, this also removes the remaining true-positive
  > unused dev-deps and records explicit cargo-udeps ignores for current
  > false positives / intentional cases: ratatui-core critical-section,
  > ratatui-crossterm's duplicate crossterm version feature shape, and
  > ratatui-termwiz's doc-example-only ratatui dev-dependency.
  >
  > I searched existing issues and PRs for udeps / cargo-udeps / "cargo
  > udeps". I did not find prior ratatui discussion about adopting
  > cargo-udeps; the only hits were Dependabot PR bodies for
  > taiki-e/install-action release notes mentioning cargo-udeps version
  > updates, for example #1971, #2095, #2194, and #2522.
  >
  > Validation:- cargo xtask udeps
  > - cargo xtask format --check
  >
  > ---------

- [4a63d41](https://github.com/ratatui/ratatui/commit/4a63d41b21b730e1986d95853596d1df527d76b4) *(uncategorized)* Remove unused dependencies by `@KikiKian` in [#2598](https://github.com/ratatui/ratatui/pull/2598)

  > Audit removes these dependencies that are not used:
  >
  >   ratatui/Cargo.toml — Removed from [dev-dependencies]:
  >   - futures
  >   - rand_chacha
  >   - tokio
  >   - tracing
  >   - tracing-appender
  >   - tracing-subscriber
  >
  > ratatui-core/Cargo.toml — Moved from [dependencies] →
  > [dev-dependencies]:
  >   - indoc
  >
  > ---------

### Continuous Integration

- [36854ef](https://github.com/ratatui/ratatui/commit/36854ef4f1af3dd551988e0af000e4eec43ebc74) *(uncategorized)* Add auto-merge required gate by `@joshka` in [#2596](https://github.com/ratatui/ratatui/pull/2596)

  > ## Summary
  >
  > This makes GitHub auto-merge usable for Ratatui PRs once maintainers are
  > happy with the change but CI is still running.
  >
  > The workflow change adds a single aggregate `required` job to the main
  > CI workflow. The repository now has [auto-merge
  > enabled](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/managing-auto-merge-for-pull-requests-in-your-repository)
  > and an `ensure checks pass`
  > [ruleset](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/about-rulesets)
  > that requires that `required` status context on `main`.
  >
  > ## Why
  >
  > Without a required status context, GitHub's auto-merge button is not
  > useful for the maintainer flow we want. The goal is to let a maintainer
  > review a PR, decide it is ready, click auto-merge, and move on without
  > coming back later just to check whether the remaining jobs finished.
  >
  > This does not relax the merge policy. GitHub's own auto-merge behavior
  > is to merge only after all required reviews and required status checks
  > are satisfied. This change gives GitHub a stable required status to wait
  > on automatically.
  >
  > ## Precedent
  >
  > I have been using this same auto-merge pattern in
  > [`ratatui/tui-widgets`](https://github.com/ratatui/tui-widgets), where
  > it has worked well for the intended maintainer flow: once a PR looks
  > ready, I can enable auto-merge and let GitHub merge it after the
  > remaining checks and review requirements are satisfied.
  >
  > ## How it works
  >
  > The new `required` job depends on the main CI jobs in
  > `.github/workflows/ci.yml` and always runs after them. It fails if any
  > required dependency fails, is cancelled, or is skipped.
  >
  > The repository ruleset requires only this aggregate `required` context
  > instead of requiring every individual matrix job separately. That gives
  > GitHub one stable status to wait on while preserving the existing CI
  > coverage.
  >
  > ## Things to know
  >
  > - Auto-merge is opt-in per PR. Maintainers still choose when to click
  > it.
  > - It does not skip review requirements, status checks, labels, or any
  > other protection rule.
  > - A PR with auto-merge enabled can still show as blocked while checks or
  > required reviews are pending. That is expected.
  > - If something needs to merge normally, maintainers can still use the
  > regular merge path or an allowed ruleset bypass. This is a convenience
  > path, not a hard blocker.
  > - Existing open PRs may need a rebase or synchronize event after this
  > lands so they pick up the new `required` workflow job.
  > - If a new required CI job is added later, it should be added to the
  > `required.needs` list or it will not be represented by the aggregate
  > gate.
  > - Jobs that are intentionally allowed to fail should be handled
  > carefully before adding them to `required.needs`, because skipped,
  > cancelled, and failed dependencies make the aggregate fail.
  >
  > ## Current PR state
  >
  > Auto-merge is already enabled on this PR. If you approve it and the
  > required checks pass, GitHub will squash-merge it automatically;
  > approving it is enough to let the PR merge once the remaining
  > requirements are satisfied.
  >
  > ## GitHub docs
  >
  > - [Automatically merging a pull
  > request](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/incorporating-changes-from-a-pull-request/automatically-merging-a-pull-request)
  > - [Managing auto-merge for pull requests in your
  > repository](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/managing-auto-merge-for-pull-requests-in-your-repository)
  > - [About
  > rulesets](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/about-rulesets)
  > - [Require status checks to pass before
  > merging](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/managing-rulesets/available-rules-for-rulesets#require-status-checks-to-pass-before-merging)
  > - [About status
  > checks](https://docs.github.com/articles/about-status-checks)
  > - [Troubleshooting required status
  > checks](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/collaborating-on-repositories-with-code-quality-features/troubleshooting-required-status-checks)
  >
  > ## Validation
  >
  > - `ruby -e 'require "yaml"; YAML.load_file(".github/workflows/ci.yml");
  > puts "ok"'`
  > - `actionlint .github/workflows/ci.yml`
  > - Verified `ratatui/ratatui` has `allow_auto_merge: true`
  > - Verified the active `ensure checks pass` ruleset requires status
  > context `required`
  > - Verified this PR has squash auto-merge enabled and is blocked pending
  > checks/review

### New Contributors

* `@satyakwok` made their first contribution in [#2594](https://github.com/ratatui/ratatui/pull/2594)
* `@KikiKian` made their first contribution in [#2598](https://github.com/ratatui/ratatui/pull/2598)

**Full Changelog**: https://github.com/ratatui/ratatui/compare/ratatui-v0.30.1...ratatui-v0.30.2