rust/Processes.md

This document outlines processes regarding management of rustfmt.

Stabilising an Option

In this Section, we describe how to stabilise an option of the rustfmt's configuration.

Conditions

• Is the default value correct ?
• The design and implementation of the option are sound and clean.
• The option is well tested, both in unit tests and, optimally, in real usage.
• There is no open bug about the option that prevents its use.

Steps

Open a pull request that closes the tracking issue. The tracking issue is listed beside the option in Configurations.md.

• Update the Config enum marking the option as stable.
• Update the the Configuration.md file marking the option as stable.
• Update CHANGELOG.md marking the option as stable.

After the stabilisation

The option should remain backward-compatible with previous parameters of the option. For instance, if the option is an enum enum Foo { Alice, Bob } and the variant Foo::Bob is removed/renamed, existing use of the Foo::Bob variant should map to the new logic. Breaking changes can be applied under the condition they are version-gated.

Make a Release

0. Update CHANGELOG.md

1. Update Cargo.toml and Cargo.lock

For example, 1.0.0 -> 1.0.1:

-version = "1.0.0"
+version = "1.0.1"

2. Push the commit to the master branch

E.g., 5274b49caa

3. Create a release tag

git tag -s v1.2.3 -m "Release 1.2.3"

4. Publish to crates.io

cargo publish

5. Create a PR to rust-lang/rust to update the rustfmt submodule

Note that if you are updating rustc-ap-* crates, then you need to update every submodules in the rust-lang/rust repository that depend on the crates to use the same version of those.

As of 2019/05, there are two such crates: rls and racer (racer depends on rustc-ap-syntax and rls depends on racer, and rls is one of submodules of the rust-lang/rust repository).