Add rust-toolchain.toml and bump to Rust 1.94 (#485)

* Introduce `rust-toolchain.toml`

So all CI builds and all local builds use the same Rust version

* Bump to Rust 1.94

Which is required for let chains, which we use!

Author: DavisVaughan

.github/workflows/build-linux.yml

@@ -3,9 +3,6 @@ name: "Build Linux"
 on:
   workflow_call:
 
-env:
-  RUST_TOOLCHAIN: "1.87"
-
 jobs:
   build:
     name: "Build Linux (${{ matrix.this.target }})"

.github/workflows/build-mac.yml

@@ -3,9 +3,6 @@ name: "Build macOS"
 on:
   workflow_call:
 
-env:
-  RUST_TOOLCHAIN: "1.87"
-
 jobs:
   build:
     name: "Build macOS (${{ matrix.this.target }})"

.github/workflows/build-windows.yml

@@ -3,9 +3,6 @@ name: "Build Windows"
 on:
   workflow_call:
 
-env:
-  RUST_TOOLCHAIN: "1.87"
-
 jobs:
   build:
     name: "Build Windows (${{ matrix.this.target }})"

CLAUDE.md

@@ -4,7 +4,7 @@
 
 Air is an R language server and formatter written in Rust. Workspace crate layout under `crates/` with a CLI binary in `crates/air/`.
 
-- Edition 2024, Rust 1.87+
+- Rust edition and version are reported in workspace level `Cargo.toml`
 - Uses `biome_formatter` for the formatting engine and `ignore` crate for file walking
 - Config file: `air.toml` discovered by walking up directory ancestors
 - Snapshot testing with `insta`

Cargo.toml

@@ -5,7 +5,7 @@ members = ["crates/*", "editors/zed", "xtask/codegen"]
 [workspace.package]
 authors = ["Posit Software, PBC"]
 edition = "2024"
-rust-version = "1.87"
+rust-version = "1.94"
 homepage = "https://github.com/posit-dev/air"
 repository = "https://github.com/posit-dev/air"
 license = "MIT"

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "1.94"