From f43bcb502435ccd99e163671204371dd8b62024f Mon Sep 17 00:00:00 2001 From: Owen Jacobson Date: Wed, 17 Jun 2020 19:05:53 -0400 Subject: Move from rust-toolchain to rustup overrides for rust version selection. This is a complicated one. There are a few factors in action here: * For background, the `maud` library requires nightly. The macro shenanigans it pulls are not supported on stable. * Travis installs Rust "cold," with no prior Rust installation, using `rustup`, for each entry in the build matrix. Travis _always_ uses the "minimal" profile. * Since 2020-06-10, the "nightly" release of the Rust language has not included the `rustfmt` component. Note that the information on that page is likely to be different by the time you look at it. * The Travis test suite requires `rustfmt` to validate commits. See `.travis.yml` for that one. * Rustup will prefer `rust-toolchain` files over command-line options when selecting a Rust version to install. Because of this wide range of factors, since the eleventh, it has not been possible to run `rustfmt` via `cargo fmt` on Travis. Tests have been broken since we added `rustfmt` as a mandatory step. This change causes Travis to use both a known-good nightly (June 10th's), and also to try the build with current nightly. Current nightly is permitted to fail; once this starts passing, we can make that build mandatory and reinstate `rust-toolchain`. Note that this doesn't affect most developers, as they use `rustup`'s default profile, which always includes `rustfmt`. `rustup` accomplishes this by walking back in time until it finds a nightly build that includes all the components in the profile, but it only does this when installing a fresh toolchain, not when trying to add a component to an installed toolchain. I would vastly prefer to keep `rust-toolchain`, but it interferes with `rustup`'s installation logic, so it has to go for now. Score one for never using `nightly`... --- README.md | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'README.md') diff --git a/README.md b/README.md index cfdd2f2..9cffd6d 100644 --- a/README.md +++ b/README.md @@ -13,6 +13,12 @@ I thought this was such a good idea, I turned it into a web bot. Want to work on this code, or run it yourself? Install the following: * [An installed copy of the Rust toolchain](https://rustup.rs). +* The `nightly` toolchain: + + ```bash + rustup toolchain add nightly + rustup override set nightly + ``` Building, testing, &c follow Rust norms: use [Cargo](https://doc.rust-lang.org/cargo/guide/working-on-an-existing-project.html) -- cgit v1.2.3