@cfxlabsinc/nx-bun-test

Infers a test target for every package, running bun test.

Replaces the test target @nx/vitest used to contribute. Nx's targetDefaults can only augment a target that already exists, so without an inference plugin every package would need to declare "test": {} by hand.

What it infers

bun test <projectRoot>/ --pass-with-no-tests [--preload ./<projectRoot>/<preload>]
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plus a coverage configuration that adds --coverage --coverage-reporter=lcov.

• --pass-with-no-tests — the target is inferred for every package, the same way the vitest one was; a package with no tests is not a failure.
• No --parallel / --isolate. bun already runs one package's files sequentially in a single process, which is what the surfpool and Temporal suites need — they previously spelled it pool: "forks" + fileParallelism: false in their vite configs. Adding either for speed would silently reintroduce those collisions.

Cache inputs and outputs

inputs:  default
         ^production
         {workspaceRoot}/bunfig.toml
         {workspaceRoot}/tools/test/**/*
outputs: {workspaceRoot}/coverage/{projectRoot}
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• default, not production — production drops *.test.ts, which is the one thing this target exists to run. ^production on the dependency side is right, though: an upstream package's own tests can't change this one's result.
• The two {workspaceRoot} entries. The command runs with cwd = workspace root, so the root bunfig.toml is the only one bun reads, and it decides both what gets collected (pathIgnorePatterns) and what runs before every file ([test].preload → tools/test/). Neither is reachable from default — that's {projectRoot}/**/* plus sharedGlobals, and sharedGlobals is only tsconfig.base.json. Without them, dropping the global timeout or changing an ignore pattern leaves every test cache warm and wrong.
• outputs is declared for both configurations because only the coverage one writes it and Nx configurations carry executor options alone — outputs is target-level and can't be narrowed per configuration. A plain test run captures nothing.

Not covered: the root package.json / bun.lock. A dependency bump doesn't invalidate any test cache — that's a workspace-wide gap (build has it too) and belongs in sharedGlobals, not here.

Preloads

A package opts in by having the file; there is no per-package project.json wiring.

A preload's module body executes once per bun test invocation, and a top-level afterAll fires after the final test file — the same once-per-package-with-teardown contract globalSetup provided.

The per-test timeout is set once in tools/test/preload.ts, wired via [test].preload in bunfig.toml, rather than testTimeout: 0 in every package.