Vitest spins endlessly when monorepo contains "too many" tests

[tjprescott]

Describe the bug

I'm running Vitest in a monorepo that has a lot of packages and a lot of tests. I'm using the Vitest extension with VSCode's test explorer. When I try to "run all" the tests just all spin endlessly or are marked as "not yet running". An examination of the logs reveals that it is basically passing a command line with the path to every test file, and when that command line is too long it just exits with code 1 and spins endlessly.

Reproduction

1. Clone: https://github.com/Azure/typespec-azure
2. Install the Vitest extension in VSCode
3. Run pnpm install
4. Discover tests and choose "Run All" from the test explorer
5. Go to Output tab for Vitest. You should see (or at least I do!) a trace that ends with...

[INFO 11:01:55 AM] [RUN.cwd] C:/repos/typespec-azure
[Error 11:01:55 AM] Process exited with code 1
[INFO 11:01:55 AM] WS Close
[INFO 11:01:55 AM] The command line is too long.

[INFO 11:01:55 AM] The command line is too long.

System Info

System:
    OS: Windows 11 10.0.22631
    CPU: (16) x64 AMD EPYC 7763 64-Core Processor
    Memory: 43.95 GB / 63.95 GB
  Binaries:
    Node: 18.17.0 - C:\Program Files\nodejs\node.EXE
    npm: 9.6.7 - C:\Program Files\nodejs\npm.CMD
    pnpm: 8.12.0 - C:\.tools\.npm-global\pnpm.CMD
  Browsers:
    Edge: Chromium (121.0.2277.128)
    Internet Explorer: 11.0.22621.1

Used Package Manager

npm

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[sheremet-va]

This should be fixed in pre-release 0.5.0 and higher. Note that the extension now requires Vitest 1.4.0 or higher.