Recognize the override file `rust-toolchain`
See original GitHub issuerustup show automatically installs an overridden toolchain if you have an override file rust-toolchain (Is it a bug? or a feature?).
This unexpected feature(?) of rust show makes toolchain action installs toolchains twice for the example in the README.md if you have the override file. An overridden toolchain is installed on rustup show and an nightly toolchain is installed after that.
It take 35 seconds per toolchain. I know it is not a large amount of time, but it bothers me when there’s a short task like
CHANGE: I found that it doesn’t call 'rustup show` anymore on the master branch.rustfmt (It takes < 3 seconds for my project).
Also, I think it is duplicated to put toolchain in the workflow’s input when you have the override file.
Can we automatically recognize the override file to fix this?
Issue Analytics
- State:
- Created 4 years ago
- Reactions:2
- Comments:5 (4 by maintainers)

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@thomaseizinger of course! I’m a bit short on a time right now, so any PRs would be really appreciated! Your flow of
rust-toolchain -> toolchain input -> errorseems to be best option here and it will also maintain the backwards compatibility, which is great.@svartalf How about making the
toolchainargument optional and falling back to therust-toolchainfile if it is not given? There should be no breakage this way.Also, we could default to
stableif neither atoolchainargument nor arust-toolchainfile is given.