## Why
Mixed prose lines that contained URLs started taking the URL-preserving
wrapping path, but that path could split ordinary words mid-token. A
follow-up issue remained in scrollback insertion: when already-rendered
indented rows were wrapped again, continuation rows could lose their
margin and fall back to terminal hard wrapping. Together those bugs made
normal Markdown output look broken around links, lists, blockquotes, and
indented content.
Separately, the local argument-comment lint wrappers failed under
environments that set `PYTHONSAFEPATH=1`, because Python no longer adds
the script directory to `sys.path` automatically. That prevented the
lint from reaching Rust callsites at all.
<img width="1778" height="1558" alt="CleanShot 2026-05-09 at 11 51 38"
src="https://github.com/user-attachments/assets/9274d150-1757-4f1a-89ac-5bdc9997d8cb"
/>
## What Changed
- Preserve URL tokens without turning every neighboring prose word into
a character-level split point.
- Add a mixed URL/prose wrapper that keeps ordinary words whole,
preserves leading whitespace, and re-splits long non-URL tokens against
the actual width available on continuation rows.
- Reuse a rendered history row's leading whitespace as the continuation
indent when scrollback insertion has to pre-wrap it again.
- Add regression coverage for markdown wrapping, history-cell rendering,
scrollback continuation margins, leading-indent width accounting, and
continuation-row re-splitting.
- Make both argument-comment lint entrypoints explicitly add their own
directory to `sys.path`, so sibling imports still work when
`PYTHONSAFEPATH=1`.
## How to Test
1. Start Codex and render a long Markdown response that mixes prose with
inline links, blockquotes, lists, and indented code-like text.
2. Confirm that ordinary words next to links stay whole instead of
breaking mid-word.
3. Resize or replay the transcript and confirm wrapped continuation rows
keep their expected left margin for blockquotes, lists, and indented
content.
4. Run the source argument-comment lint from a shell with
`PYTHONSAFEPATH=1` and confirm it starts normally instead of failing to
import `wrapper_common`.
Targeted tests:
- `cargo test -p codex-tui mixed_line --lib`
- `cargo test -p codex-tui preserves_prefix_on_wrapped_rows --lib`
- `cargo test -p codex-tui
agent_markdown_cell_does_not_split_words_after_inline_markdown --lib`
- `cargo test -p codex-tui
mixed_url_markdown_wraps_prose_without_splitting_words_snapshot --lib`
- `python3 tools/argument-comment-lint/test_wrapper_common.py`
- `just argument-comment-lint-from-source -p codex-tui -- --lib`
Notes:
- `cargo test -p codex-tui` currently reaches the new tests
successfully, then still aborts in the pre-existing
`tests::fork_last_filters_latest_session_by_cwd_unless_show_all`
stack-overflow failure.
## Why
The `argument-comment-lint` entrypoints had grown into two shell
wrappers with duplicated parsing, environment setup, and Cargo
forwarding logic. The recent `--` separator regression was a good
example of the problem: the behavior was subtle, easy to break, and hard
to verify.
This change rewrites those wrappers in Python so the control flow is
easier to follow, the shared behavior lives in one place, and the tricky
argument/defaulting paths have direct test coverage.
## What changed
- replaced `tools/argument-comment-lint/run.sh` and
`tools/argument-comment-lint/run-prebuilt-linter.sh` with Python
entrypoints: `run.py` and `run-prebuilt-linter.py`
- moved shared wrapper behavior into
`tools/argument-comment-lint/wrapper_common.py`, including:
- splitting lint args from forwarded Cargo args after `--`
- defaulting repo runs to `--manifest-path codex-rs/Cargo.toml
--workspace --no-deps`
- defaulting non-`--fix` runs to `--all-targets` unless the caller
explicitly narrows the target set
- setting repo defaults for `DYLINT_RUSTFLAGS` and `CARGO_INCREMENTAL`
- kept the prebuilt wrapper thin: it still just resolves the packaged
DotSlash entrypoint, keeps `rustup` shims first on `PATH`, infers
`RUSTUP_HOME` when needed, and then launches the packaged `cargo-dylint`
path
- updated `justfile`, `rust-ci.yml`, and
`tools/argument-comment-lint/README.md` to use the Python entrypoints
- updated `rust-ci` so the package job runs Python syntax checks plus
the new wrapper unit tests, and the OS-specific lint jobs invoke the
wrappers through an explicit Python interpreter
This is a follow-up to #16054: it keeps the current lint semantics while
making the wrapper logic maintainable enough to iterate on safely.
## Validation
- `python3 -m py_compile tools/argument-comment-lint/wrapper_common.py
tools/argument-comment-lint/run.py
tools/argument-comment-lint/run-prebuilt-linter.py
tools/argument-comment-lint/test_wrapper_common.py`
- `python3 -m unittest discover -s tools/argument-comment-lint -p
'test_*.py'`
- `python3 ./tools/argument-comment-lint/run-prebuilt-linter.py -p
codex-terminal-detection -- --lib`
- `python3 ./tools/argument-comment-lint/run.py -p
codex-terminal-detection -- --lib`
