Lazily load mixlib-shellout - #436
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mixlib-shellout costs ~9ms to require and pulls in etc, fileutils, tmpdir and fcntl (7 files). It is used in exactly one place -- shelling out from `Mixlib::Install.detect_platform` -- so load it there rather than making every consumer pay for it at require time. Measured on Ruby 4.0.6 (min of 15 fresh subprocesses): before 54.79 ms 240 loaded features after 45.40 ms 233 loaded features Compatibility note: this is the one deferral in this series with an observable effect. Code that called `Mixlib::ShellOut` after only requiring mixlib-install, without requiring mixlib-shellout itself, will now get a NameError until it adds the require. Our own functional spec did exactly that, and is fixed here. Please drop this commit if that risk is not worth ~9ms. Generated output is unchanged: all 176 golden SHA256 digests match main. Signed-off-by: Tim Smith <tsmith84@proton.me>
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Summary
mixlib-shellout costs ~9 ms to require and pulls in
etc,fileutils,tmpdirandfcntl— 7 files. It is used in exactly one place: shelling out fromMixlib::Install.detect_platform. This loads it there instead of making every consumer pay for it at require time.Measurements
Ruby 4.0.6, minimum of 15 fresh subprocesses:
Compatibility note — please read
This is the one deferral in this series with an externally observable effect, so it is deliberately split into its own PR.
Code that calls
Mixlib::ShellOutafter only requiringmixlib-install, without requiringmixlib-shelloutitself, will now get aNameErroruntil it adds the require. That is relying on a transitive require, but it is easy to do by accident — our own functional spec did exactly that, and is fixed in this PR.The three main consumers (chef, chef-cli, test-kitchen) all require mixlib-shellout directly, so I believe the risk is low. But it is a real behaviour change for ~9 ms, and it is entirely reasonable to close this one and keep the other load-time PRs in this series. Happy either way.
Verification
chefstyleclean.Mixlib::Install.detect_platformverified working in a bare process:Mixlib::ShellOutis undefined at load, defined after the call, and the returned platform hash is correct.main.