SubMiner/backlog/tasks/task-281 - Prevent-Windows-launcher-tests-from-leaking-backslash-temp-files-on-POSIX.md

id, title, status, assignee, created_date, updated_date, labels, dependencies, documentation, priority

id	title	status	assignee	created_date	updated_date	labels	dependencies	documentation	priority
TASK-281	Prevent Windows launcher tests from leaking backslash temp files on POSIX	Done	codex	2026-04-05 21:13	2026-04-05 21:20	tests launcher bug		/home/sudacode/github/SubMiner2/AGENTS.md	medium

Description

Windows-specific launcher tests in launcher/mpv.test.ts currently create real filesystem entries using path.win32.join(...) with a POSIX mkdtemp base. On Linux/macOS this produces literal backslash-named paths like \tmp\subminer-test-win-dir-* inside the repo/worktree, and the existing cleanup only removes the POSIX /tmp base directory. Fix the tests so they still cover Windows path resolution behavior without leaking stray files into the working tree.

Acceptance Criteria

• #1 Running the Windows findAppBinary tests on a POSIX host does not create new untracked \tmp\subminer-test-win-* files in the repository root.
• #2 The Windows launcher tests still validate PATH and install-directory resolution behavior.
• #3 Relevant launcher tests pass after the change.

Implementation Plan

1. Add a regression test in launcher/mpv.test.ts that exercises the Windows findAppBinary cases on a POSIX host and asserts they do not leave new backslash-named temp artifacts in the repository root.
2. Refactor the Windows launcher tests to avoid creating real filesystem paths from path.win32.join(...) on POSIX; keep Windows path assertions via stubs and only create real files with native POSIX paths where needed.
3. Run the targeted launcher tests and confirm no new \tmp\subminer-test-win-* artifacts appear in git status.

Implementation Notes

Investigation: reproduced the leak locally. The source is launcher/mpv.test.ts Windows findAppBinary tests that combine a POSIX mkdtemp base with path.win32.join(...), creating literal backslash-named entries like \tmp\subminer-test-win-dir-* in the repo root. Existing cleanup only removes the POSIX /tmp base directory.

User approved implementation plan on 2026-04-05.

Implemented in launcher/mpv.test.ts by replacing the leaky Windows PATH/install-directory helpers with pure fs stubs (access/exists/stat) and fixed Windows path strings instead of creating real path.win32 filesystem entries on POSIX. Added a regression test that snapshots repo-root \tmp\subminer-test-win-* artifacts before/after running the Windows cases and asserts no new entries are created.

Verification: bun test launcher/mpv.test.ts --test-name-pattern 'findAppBinary Windows cases do not leak backslash temp artifacts on POSIX|findAppBinary resolves SubMiner.exe on PATH on Windows|findAppBinary resolves a Windows install directory to SubMiner.exe' passed (3/3). bun test launcher/mpv.test.ts still has one unrelated pre-existing sandbox failure in launchAppCommandDetached handles child process spawn errors because the test opens ~/.config/SubMiner/logs/app-2026-04-05.log and hits EROFS in this environment.

Final Summary

Reworked the Windows findAppBinary tests in launcher/mpv.test.ts so they no longer create real backslash-named temp files on POSIX hosts. The PATH and install-directory cases now use synthetic Windows path strings plus fs.accessSync / fs.existsSync / fs.statSync stubs to exercise the same resolver behavior without writing \\tmp\\subminer-test-win-* entries into the repository root.

Added a POSIX regression test that snapshots existing repo-root \\tmp\\subminer-test-win-* artifacts, runs the Windows path-resolution cases, and asserts the artifact set is unchanged. This catches future regressions where a Windows-path test accidentally writes literal backslash paths on Linux/macOS.

Tests run:

• bun test launcher/mpv.test.ts --test-name-pattern 'findAppBinary Windows cases do not leak backslash temp artifacts on POSIX|findAppBinary resolves SubMiner.exe on PATH on Windows|findAppBinary resolves a Windows install directory to SubMiner.exe'
• bun test launcher/mpv.test.ts (all relevant findAppBinary tests passed; one unrelated existing sandbox failure remains in launchAppCommandDetached handles child process spawn errors due EROFS opening ~/.config/SubMiner/logs/...)