test(backends): add unit coverage for nativeToolRuntime shims

[aaight]

Summary

• Adds tests/unit/backends/nativeToolRuntime.test.ts with 15 unit tests covering createNativeToolRuntimeArtifacts and buildNativeToolPath
• Verifies shim directory creation, gh shim file existence, executable permissions, and best-effort cleanup
• Verifies PATH construction: shim-first ordering, CLI tools inclusion, base PATH preservation, and filtering of empty/undefined entries

Test plan

• createNativeToolRuntimeArtifacts — shim dir created on disk
• createNativeToolRuntimeArtifacts — gh shim file exists
• createNativeToolRuntimeArtifacts — gh shim contains correct shell script content
• createNativeToolRuntimeArtifacts — gh shim has executable permissions (0o755)
• createNativeToolRuntimeArtifacts — cleanup removes shim directory
• createNativeToolRuntimeArtifacts — double-cleanup does not throw (best-effort)
• createNativeToolRuntimeArtifacts — two consecutive calls produce unique directories
• buildNativeToolPath — shim dir placed first
• buildNativeToolPath — cliToolsDir placed before basePath
• buildNativeToolPath — basePath preserved at end
• buildNativeToolPath — shimDir omitted when not provided
• buildNativeToolPath — works with only cliToolsDir
• buildNativeToolPath — filters empty string entries
• buildNativeToolPath — filters undefined basePath
• buildNativeToolPath — correct full ordering with all three entries

Trello card: https://trello.com/c/Y4JTi0vG/564-as-a-developer-i-want-unit-coverage-for-native-tool-runtime-shims-so-that-cascade-native-tool-execution-stays-predictable

🤖 Generated with Claude Code

🕵️ claude-code · claude-sonnet-4-6 · run details

[nhopeatall]

LGTM — well-structured unit tests that directly exercise both exported functions from nativeToolRuntime.ts. Tests cover the key behaviors (filesystem creation, shim content, permissions, cleanup idempotency, PATH ordering, and filtering) without over-mocking. All CI checks pass.

Nitpick

• tests/unit/backends/nativeToolRuntime.test.ts:2 — beforeEach is imported from vitest but never used in the file. Only afterEach is used.

🕵️ claude-code · claude-opus-4-6 · run details