reckless: process hung in CI

[daywalker90]

I tried reckless through the recklessrpc plugin like this:

l1 = node_factory.get_node()
l1.rpc.call("reckless", ["source", "remove", "https://github.com/lightningd/plugins"])

and this works on my machine with CLN v25.12 just fine but on the CI, also v25.12, i get:

lightningd-1 2025-12-05T16:07:44.179Z DEBUG   plugin-recklessrpc: calling: reckless -v --json -l /tmp/ltests-lpr9tg9f/test_program_1/lightning-1/ --network regtest source remove https://github.com/lightningd/plugins (null)
lightningd-1 2025-12-05T16:07:44.271Z DEBUG   plugin-recklessrpc: confirming config creation
lightningd-1 2025-12-05T16:07:44.291Z DEBUG   plugin-recklessrpc: reckless failed to exit, killing now.

error: {'code': -3, 'message': 'reckless process hung'}

Now if i try this in the CI:

l1 = node_factory.get_node()

ln_dir = str(Path(l1.info["lightning-dir"]).parent)
subprocess.run(
         [
             "reckless",
             "-v",
             "--json",
             "-l",
             ln_dir,
             "--network",
             "regtest",
             "source",
             "remove",
             "https://github.com/lightningd/plugins",
         ],
         input="Y\n",
         text=True,
         capture_output=True,
     )

it works.

[endothermicdev]

I'm still not sure of the exact root cause, but the plugin was definitely having trouble finding the reckless executable in the system path (even though running it as subprocess works fine as you point out.) I tried a few different ways to resolve this in #8630 including passing the location of the executable as an argument to the reckless-rpc plugin, but ultimately went with manually prepending PATH in the pytest environment before running the reckless tests. I think that should be sufficient for CI use and local testing of test_reckless.py at least. Let me know if there's another test scenario that needs to be addressed.