[Lldb-commits] [lldb] [lldb][test] Enforce `pexpect` system availability by default (PR #84270)

[Jordan Rupprecht via lldb-commits]

rupprecht wrote:

@mysterymath do you run the API test suites with that custom python, i.e. `ninja check-lldb-api`? If so, would you be able to add bundle `pexpect` for your tests even if it's not in what you ship?

The goal is to be able to delete https://github.com/llvm/llvm-project/tree/main/lldb/third_party/Python/module/pexpect-4.6. This library is only used in the API tests.

The goal of the cmake check here is to be able to have an ~immediate feedback loop that `pexpect` needs to be installed, instead of waiting a long time until `ninja check-lldb-api` runs the tests and discovers that `import pexpect` fails. If you don't run these tests, but the cmake warning is still blocking you, maybe we should just remove the check. `LLDB_ENFORCE_STRICT_TEST_REQUIREMENTS` serves essentially the same purpose but is opt-in.

https://github.com/llvm/llvm-project/pull/84270