Migrate test terminal emulator from vt100 to rio-vt

[raphamorim]

Swaps the redraw tests' terminal emulator from vt100 to rio-vt, Rio's terminal engine, behind a tiny Parser adapter in src/test.rs that keeps the same process / screen().contents() / screen().cursor_position() shape. The call sites in multiselect.rs / select.rs are unchanged apart from the type name, and the full test suite passes (the cursor-drift and frame-shrink redraw assertions hold identically).

rio-vt is a safe-Rust, dependency-light terminal core (VT state machine, grid, parser) and is actively maintained — the swap also drops the transitive net2 (RUSTSEC-2020-0016) that older terminal parsers pull in.

• Benchmark against vt100 and alacritty_terminal: https://github.com/raphamorim/rio-vt-benchmark
• Background on the engine: https://rioterm.com/blog/2026/07/27/rio-vt-and-librio

Summary by CodeRabbit

• Tests
  • Improved Unix terminal test emulation by switching from the previous vt100-based parser to a shared rio-vt-backed Parser with Screen assertions.
  • Updated select and multiselect regression tests to use the shared terminal emulator for redraw and wrapped-option behavior.
  • Preserved existing redraw stability and prompt/redraw clearing coverage while updating the replay/parser wiring.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Central YAML (base), Organization UI (inherited)

Review profile: CHILL

Plan: Pro Plus

Run ID: 827d3d3d-a3ff-4d3c-a23d-53b89d61e8cb

📥 Commits

Reviewing files that changed from the base of the PR and between 34b686a and e1c9441.

📒 Files selected for processing (3)

• src/multiselect.rs
• src/select.rs
• src/test.rs

🚧 Files skipped from review as they are similar to previous changes (3)

• src/test.rs
• src/multiselect.rs
• src/select.rs

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📝 Walkthrough

Walkthrough

Unix test terminal emulation migrated from vt100 to a shared rio-vt-backed parser, with redraw regression tests updated to use the new adapter.

Changes

Terminal parser migration

Layer / File(s)	Summary
rio-vt capture adapter Cargo.toml, src/test.rs	Replaces the Unix test dependency on vt100 with rio-vt and adds parser, screen, content, cursor, and replay support.
Redraw regression test migration src/multiselect.rs, src/select.rs	Updates redraw tests to construct and use the shared test Parser while preserving their existing assertions.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Poem

A rabbit hops through bytes of light,
With rio-vt parsing screens just right.
Frames redraw, prompts stay neat,
No stacked copies underfoot or feet.
Test ears twitch: the cursor’s bright!

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: replacing vt100 with rio-vt in the test terminal emulator.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[greptile-apps]

Dependency cannot be resolved

On Unix test targets, Cargo resolves this plain version requirement through crates.io, where the requested rio-vt package is unavailable, causing the test suite to fail before compilation.

[greptile-apps]

Greptile Summary

Migrates Unix redraw-test terminal emulation from vt100 to a shared rio-vt adapter.

• Adds an adapter exposing the existing processing, screen-content, and cursor-position test interface.
• Updates selection and multiselection redraw tests to use the adapter.
• Replaces the Unix development dependency on vt100 with rio-vt.

Confidence Score: 3/5

The PR is not safe to merge until the rio-vt dependency is changed to a source Cargo can resolve.

The manifest still declares rio-vt = "0.5.1" as a plain Unix development dependency without a repository override, so Unix test runs fail during dependency resolution before compilation.

Files Needing Attention: Cargo.toml

Important Files Changed

Filename	Overview
Cargo.toml	Replaces vt100 with the unresolved plain crates.io dependency rio-vt = "0.5.1"; the previously reported resolution failure remains.
src/test.rs	Adds a Unix-only rio-vt adapter preserving the terminal-processing and screen-inspection interface used by redraw tests.
src/multiselect.rs	Switches redraw regression tests from the former parser type to the shared adapter without changing their assertions.
src/select.rs	Switches the frame-shrink regression test to the shared parser adapter without changing tested behavior.

_{Reviews (2): Last reviewed commit: "sort test imports for rustfmt" | Re-trigger Greptile}

[raphamorim]

Pushed a fix. For the record, the Greptile note about rio-vt being "unavailable from the configured registry" isn't accurate — the crate resolved and compiled fine on all three OSes (the log shows Checking demand … Finished before the failing step). The only red check was cargo fmt --check: the migrated test imports weren't sorted ({capture_term, replay, snapshot, Parser} → {Parser, capture_term, replay, snapshot}). That's fixed now; cargo fmt --check + cargo test --lib --tests are green locally.