[nextest-runner] be build directory-aware

[sunshowers]

Upcoming versions of Cargo are going to incorporate a split between the build and target directories. The build directory is for intermediate artifacts, while final build outputs are uplifted to the target directory.

Also add --build-dir-remap to PathMapper and split map_binary() into map_target_path() and map_build_path(), so the --binaries-metadata + --target-dir-remap workflow works when build_directory != target_directory.

The remapping behavior is:

build_dir in metadata	--target-dir-remap	--build-dir-remap	target_dir maps to	build_dir maps to
== target_dir	(none)	(none)	unchanged	unchanged
== target_dir	/new/tgt	(none)	/new/tgt	/new/tgt (fallback)
== target_dir	/new/tgt	/new/bld	/new/tgt	/new/bld
!= target_dir	(none)	(none)	unchanged	unchanged
!= target_dir	/new/tgt	(none)	/new/tgt	/new/tgt (fallback)
!= target_dir	(none)	/new/bld	unchanged	/new/bld
!= target_dir	/new/tgt	/new/bld	/new/tgt	/new/bld

Also add an integration test with the new build directory support.

[codecov]

Codecov Report

❌ Patch coverage is 94.48529% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.22%. Comparing base (d9c9241) to head (f3965c5).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cargo-nextest/src/reuse_build.rs	70.00%	6 Missing ⚠️
nextest-runner/src/redact.rs	58.33%	5 Missing ⚠️
nextest-runner/src/list/binary_list.rs	94.33%	3 Missing ⚠️
nextest-runner/src/errors.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3169      +/-   ##
==========================================
+ Coverage   85.19%   85.22%   +0.03%     
==========================================
  Files         158      158              
  Lines       46399    46610     +211     
==========================================
+ Hits        39529    39723     +194     
- Misses       6870     6887      +17     

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[Copilot]

Pull request overview

This PR updates nextest’s build artifact handling to support Cargo’s upcoming split between build and target directories, ensuring reuse-build, archiving, and path remapping continue to work correctly when build_directory != target_directory.

Changes:

• Add build_directory throughout Rust build metadata and update path joining/mapping for test binaries, build script outputs, and linked paths.
• Extend reuse-build remapping with --build-dir-remap, and split path mapping into map_target_path() vs map_build_path().
• Update archive metadata emission to normalize/omit build_directory, and add CI coverage for Cargo build-dir mode.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
nextest-runner/src/test_command.rs	Sets OUT_DIR based on build_directory rather than target_directory.
nextest-runner/src/reuse_build/mod.rs	Adds build-dir remap plumbing and splits path mapping into target vs build mappings.
nextest-runner/src/reuse_build/archiver.rs	Writes archive metadata via archive-specific summaries; treats test binaries/build script outputs/linked paths as build-dir relative.
nextest-runner/src/redact.rs	Updates redactions to treat linked paths as build-dir relative; adds build-dir redaction.
nextest-runner/src/list/test_list.rs	Maps test binary paths via build-dir mapping.
nextest-runner/src/list/test_helpers.rs	Updates helper construction for new RustBuildMeta::new(target, build, ...) signature.
nextest-runner/src/list/rust_build_meta.rs	Introduces build_directory and updates dylib path resolution + summary/archive summary behavior.
nextest-runner/src/list/binary_list.rs	Detects Cargo build dir when available; produces archive-specific summaries that remap test binary paths under target/.
nextest-runner/src/errors.rs	Adds BuildDir kind for PathMapper construction errors.
nextest-metadata/src/test_list.rs	Adds optional build_directory to serialized metadata with backwards-compatible defaults.
fixtures/nextest-tests/cdylib/cdylib-link/build.rs	Avoids recursive build-dir locking and supports old/new dylib output locations.
cargo-nextest/src/reuse_build.rs	Adds --build-dir-remap and applies fallback behavior when constructing PathMapper.
cargo-nextest/src/dispatch/core/tests.rs	Extends CLI argument parsing tests for --build-dir-remap constraints.
cargo-nextest/src/dispatch/core/filter.rs	Passes build_directory into path-mapper creation for reuse-build workflows.
.github/workflows/ci.yml	Adds a CI job that runs/archives fixtures with Cargo build-dir enabled and validates archive portability.

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[trunk-io]

     

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