## Summary
Turn diff updates repeatedly rendered and serialized the entire
accumulated diff after every `apply_patch`. The event path also rendered
once before updating the tracker solely to test whether a diff existed.
In production feedback CODEX-20PW, 2,589 patches across 72 paths
produced 401 notifications totaling 441 MB, with the hottest paths
patched 518 and 495 times.
This change:
- replaces the pre-update render with a cheap cached-state check
- caches each rendered file diff by path and content revision, so an
update only invokes Myers for affected paths
- caches the deterministic aggregate diff so event emission and turn
completion reuse it without recomputation
- preserves invalidation and net-zero clear notifications
- applies a 100 ms per-file `similar` timeout; ordinary files complete
far below this threshold, while pathological rewrites fall back to a
coarse unified hunk that still represents the exact final contents
The 100 ms deadline bounds synchronous tool-completion latency while
leaving substantial headroom for normal diffs. The regression test
applies the fallback diff through the repository's patch parser and
verifies byte-for-byte final contents.
## Validation
- `cargo test -p codex-core turn_diff_tracker::tests` (14 passed)
- `cargo test -p codex-core tools::events::tests` (4 passed)
- `just fix -p codex-core`
- `just fmt`
Focused coverage verifies that 42 updates across two files perform 42
file renders rather than repeatedly rendering the accumulated set,
unchanged paths are not re-diffed, clear events remain correct, and a
48,000-line near-total rewrite returns promptly and applies to the exact
expected result. The full `codex-core` suite was not used as the final
gate because an unrelated existing multi-agent test hit a stack overflow
when run during investigation.
## Bug context
- Sentry feedback: CODEX-20PW
- Correlation IDs: `019eb2a9-13d2-74e0-b690-27ee224ffb6d`,
`019e9ad7-09c3-7cb2-b728-ee3acba103ab`
## Why
Turn diffs were tracked as one flat set of absolute paths. In
multi-environment turns, local and remote environments can report the
same path while representing different filesystems, so a single path key
can collapse distinct changes or attribute them to the wrong
environment.
The environment name is **NOT** included in the generated unified diff.
This can come later.
## Summary
- replace filesystem-based turn diff tracking with an operation-backed
accumulator
- preserve enough verified apply_patch state to render move-overwrite
cases correctly
- keep the turn/diff/updated contract intact while removing remote-only
turn-diff test skips
This takes the assumption that no 3P services rely on the output format
of `apply_patch`
## Why
For the CCA file system isolation push
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
`codex-core` was re-exporting APIs owned by sibling `codex-*` crates,
which made downstream crates depend on `codex-core` as a proxy module
instead of the actual owner crate.
Removing those forwards makes crate boundaries explicit and lets leaf
crates drop unnecessary `codex-core` dependencies. In this PR, this
reduces the dependency on `codex-core` to `codex-login` in the following
files:
```
codex-rs/backend-client/Cargo.toml
codex-rs/mcp-server/tests/common/Cargo.toml
```
## What
- Remove `codex-rs/core/src/lib.rs` re-exports for symbols owned by
`codex-login`, `codex-mcp`, `codex-rollout`, `codex-analytics`,
`codex-protocol`, `codex-shell-command`, `codex-sandboxing`,
`codex-tools`, and `codex-utils-path`.
- Delete the `default_client` forwarding shim in `codex-rs/core`.
- Update in-crate and downstream callsites to import directly from the
owning `codex-*` crate.
- Add direct Cargo dependencies where callsites now target the owner
crate, and remove `codex-core` from `codex-rs/backend-client`.
## Why
PR #13783 moved the `codex.rs` unit tests into `codex_tests.rs`. This
applies the same extraction pattern across the rest of `codex-rs/core`
so the production modules stay focused on runtime code instead of large
inline test blocks.
Keeping the tests in sibling files also makes follow-up edits easier to
review because product changes no longer have to share a file with
hundreds or thousands of lines of test scaffolding.
## What changed
- replaced each inline `mod tests { ... }` in `codex-rs/core/src/**`
with a path-based module declaration
- moved each extracted unit test module into a sibling `*_tests.rs`
file, using `mod_tests.rs` for `mod.rs` modules
- preserved the existing `cfg(...)` guards and module-local structure so
the refactor remains structural rather than behavioral
## Testing
- `cargo test -p codex-core --lib` (`1653 passed; 0 failed; 5 ignored`)
- `just fix -p codex-core`
- `cargo fmt --check`
- `cargo shear`
The only file to watch is the cargo.toml
All the others come from just fix + a few manual small fix
The set of rules have been taken from the list of clippy rules
arbitrarily while trying to optimise the learning and style of the code
while limiting the loss of productivity
Created this PR by:
- adding `redundant_clone` to `[workspace.lints.clippy]` in
`cargo-rs/Cargol.toml`
- running `cargo clippy --tests --fix`
- running `just fmt`
Though I had to clean up one instance of the following that resulted:
```rust
let codex = codex;
```
This PR:
* Added the clippy.toml to configure allowable expect / unwrap usage in
tests
* Removed as many expect/allow lines as possible from tests
* moved a bunch of allows to expects where possible
Note: in integration tests, non `#[test]` helper functions are not
covered by this so we had to leave a few lingering `expect(expect_used`
checks around
This lets us show an accumulating diff across all patches in a turn.
Refer to the docs for TurnDiffTracker for implementation details.
There are multiple ways this could have been done and this felt like the
right tradeoff between reliability and completeness:
*Pros*
* It will pick up all changes to files that the model touched including
if they prettier or another command that updates them.
* It will not pick up changes made by the user or other agents to files
it didn't modify.
*Cons*
* It will pick up changes that the user made to a file that the model
also touched
* It will not pick up changes to codegen or files that were not modified
with apply_patch
Jeremy RoseandGitHub
pakrym-oaiandGitHub
Michael BolinandGitHub
Parker ThompsonandGitHub
Gabriel PealandGitHub