chore: add Rust CI

* validate that the rustutils crate is valid
* currently uses hardcoded CI script, but should move it all to justfile similar to many other similar crates
* add MSRV (tested with `cargo msrv find` + CI for it
* ensure rustutils crate is not published, and set version to 0.0.0 as it has no internal version

.github/workflows/rust-ci.yaml

@@ -0,0 +1,79 @@
+name: rust-ci
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: bash
+    working-directory: rustutils/
+
+jobs:
+  test:
+    name: Rust tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: Swatinem/rust-cache@v2
+        if: github.event_name != 'release' && github.event_name != 'workflow_dispatch'
+      - name: Test rustutils
+        run: |
+          # Eventually this script should be moved to a justfile as a "ci-test" recipe
+          # rust-info:
+          rustc --version
+          cargo --version
+          #
+          # Test code formatting
+          # test-fmt:
+          cargo fmt --all -- --check
+          #
+          # Run cargo clippy
+          # clippy:
+          cargo clippy --workspace --all-targets -- -D warnings
+          #
+          # Quick compile
+          # check:
+          RUSTFLAGS='-D warnings' cargo check --workspace --all-targets
+          #
+          # Run all tests
+          # test:
+          cargo test --workspace --all-targets
+          #
+          # Test documentation
+          # test-doc:
+          RUSTDOCFLAGS="-D warnings" cargo doc --no-deps
+
+  msrv:
+    name: Rust tests MSRV
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: Swatinem/rust-cache@v2
+        if: github.event_name != 'release' && github.event_name != 'workflow_dispatch'
+      - name: Read crate metadata
+        id: metadata
+        run: echo "rust-version=$(sed -ne 's/rust-version *= *\"\(.*\)\"/\1/p' Cargo.toml)" >> $GITHUB_OUTPUT
+      - name: Install Rust
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ steps.metadata.outputs.rust-version }}
+          components: rustfmt
+      - name: Test rustutils
+        working-directory: rustutils/
+        run: |
+          # Eventually this script should be moved to a justfile as a "ci-test-msrv" recipe
+          # rust-info:
+          rustc --version
+          cargo --version
+          #
+          # Quick compile
+          # check:
+          RUSTFLAGS='-D warnings' cargo check --workspace --all-targets
+          #
+          # Run all tests
+          # test:
+          cargo test --workspace --all-targets

rustutils/Cargo.toml

@@ -1,11 +1,13 @@
 [package]
 name = "rustutils"
-version = "0.1.0"
+version = "0.0.0"
+publish = false  # This crate is not intended to be published on crates.io
 authors = ["MapLibre contributors"]
 description = "Core Rust utilities for MapLibre Native"
 edition = "2021"
 license = "BSD-2-Clause"
 repository = "https://github.com/maplibre/maplibre-native"
+rust-version = "1.78.0"
 
 [lib]
 crate-type = ["staticlib"]