Set environment variables before running rust-cache

Show how the related rustfmt action can be used.

.github/dependabot.yml

@@ -0,0 +1,11 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "monthly"

.github/workflows/ci.yml

@@ -13,9 +13,28 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        rust: [nightly, beta, stable]
+        rust: [
+          # Test with toolchain file override
+          "1.50",
+          "nightly",
+          "beta",
+          "stable",
+        ]
     steps:
       - uses: actions/checkout@v3
+      # Test toolchain file support
+      - name: Write rust-toolchain.toml
+        run: |
+          cat <<EOF >>rust-toolchain.toml
+          [toolchain]
+          channel = "nightly-2020-07-10"
+          components = [ "rustfmt", "rustc-dev" ]
+          targets = [ "wasm32-unknown-unknown", "thumbv2-none-eabi" ]
+          profile = "minimal"
+          EOF
+        shell: bash
+        if: matrix.rust == '1.50'
+
       - uses: ./
         name: Run actions-rust-lang/setup-rust-toolchain ${{matrix.rust}}
         id: toolchain

CHANGELOG.md

@@ -0,0 +1,52 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.2.1] - 2022-07-29
+
+### Fixed
+
+* Set environment variables before invoking the cache action.
+    This ensures restoring and saving are using the same cache key.
+
+## [1.2.0] - 2022-07-21
+
+### Added
+
+* Prefer toolchain definitions in `rust-toolchain` or `rust-toolchain.toml` files ([Toolchain File](https://rust-lang.github.io/rustup/overrides.html#the-toolchain-file)).
+    Other input values are ignored if either file is found.
+
+## [1.1.0] - 2022-07-19
+
+### Added
+
+* Install rustup if not available in the CI environment. (Linux only)
+    The code is taken from this issue: <https://github.com/dtolnay/rust-toolchain/pull/8>
+* Add rustc version output suitable as a cache key.
+    This is based on <https://github.com/dtolnay/rust-toolchain/pull/20> and <https://github.com/dtolnay/rust-toolchain/pull/17>.
+
+### Changed
+
+* Update to `Swatinem/rust-cache@v2`.
+
+## [1.0.2] - 2022-05-02
+
+### Changed
+
+* Enable colored cargo output.
+* Print short backtraces during test failure.
+
+## [1.0.1] - 2022-04-20
+
+### Added
+
+* Release action on marketplace
+
+## [1.0.0] - 2022-04-20
+
+Initial Version

README.md

@@ -24,11 +24,26 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions-rust-lang/setup-rust-toolchain@v1
       - run: cargo test --all-features
+ 
+  # Check formatting with rustfmt
+  formatting:
+    name: cargo fmt
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      # Ensure rustfmt is installed and setup problem matcher
+      - uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: rustfmt
+      - name: Rustfmt Check
+        uses: actions-rust-lang/rustfmt@v1
 ```
 
 ## Inputs
 
 All inputs are optional.
+If a [toolchain file](https://rust-lang.github.io/rustup/overrides.html#the-toolchain-file) (i.e., `rust-toolchain` or `rust-toolchain.toml`) is found in the root of the repository, it takes precedence.
+All input values are ignored if a toolchain file exists.
 
 | Name         | Description                                                                       | Default |
 | ------------ | --------------------------------------------------------------------------------- | ------- |

action.yml

@@ -1,8 +1,7 @@
 name: Setup Rust Toolchain for GitHub CI
 description: |
-  Setup specific Rust versions and integrate nicely into the ecosystem.
-  The action enabled caching of Rust tools and build artifacts and sets environment variables for faster and more efficient caching.
-  It also sets up problem matchers showing compilation and formatting issues.
+  Setup specific Rust versions with caching pre-configured.
+  It provides problem matchers for cargo and rustfmt issues.
 
 branding:
   icon: "play"
@@ -34,6 +33,9 @@ outputs:
   rustup-version:
     description: "Version as reported by `rustup --version`"
     value: ${{steps.versions.outputs.rustup-version}}
+  cachekey:
+    description: A short hash of the rustc version, appropriate for use as a cache key. "20220627a831"
+    value: ${{steps.versions.outputs.cachekey}}
 
 runs:
   using: composite
@@ -48,30 +50,54 @@ runs:
         targets: ${{inputs.target}}
         components: ${{inputs.components}}
       shell: bash
-    - name: rustup toolchain install ${{inputs.toolchain}}
-      run: |
-        rustup toolchain install ${{inputs.toolchain}}${{steps.flags.outputs.targets}}${{steps.flags.outputs.components}} --profile minimal${{steps.flags.outputs.downgrade}} --no-self-update
-        rustup default ${{inputs.toolchain}}
-      shell: bash
-    - name: Print installed versions
-      id: versions
-      run: |
-        echo "::set-output name=rustc-version::$(rustc --version)"
-        rustc --version
-        echo "::set-output name=cargo-version::$(cargo --version)"
-        cargo --version
-        echo "::set-output name=rustup-version::$(rustup --version)"
-        rustup --version
-      shell: bash
-
-    - name: "Setup Rust Caching"
-      uses: Swatinem/rust-cache@v1
-    - name: "Install Rust Problem Matcher"
-      run: echo "::add-matcher::${{ github.action_path }}/rust.json"
-      shell: bash
+    # The environment variables always need to be set before the caching action
     - name: "Setting Environment Variables"
       run: |
         echo "CARGO_INCREMENTAL=0" >> $GITHUB_ENV
         echo "CARGO_PROFILE_DEV_DEBUG=0" >> $GITHUB_ENV
+        echo "CARGO_TERM_COLOR=always" >> $GITHUB_ENV
+        echo "RUST_BACKTRACE=short" >> $GITHUB_ENV
         echo "RUSTFLAGS=-D warnings" >> $GITHUB_ENV
       shell: bash
+    - name: "Install Rust Problem Matcher"
+      run: echo "::add-matcher::${{ github.action_path }}/rust.json"
+      shell: bash
+
+    - name: Install rustup, if needed
+      run: |
+        if ! command -v rustup &> /dev/null ; then
+          curl --proto '=https' --tlsv1.2 --retry 10 --retry-connrefused -fsSL "https://sh.rustup.rs" | sh -s -- --default-toolchain none -y
+          echo "${CARGO_HOME:-~/.cargo}/bin" >> $GITHUB_PATH
+        fi
+      if: runner.os != 'Windows'
+      shell: bash
+    - name: rustup toolchain install ${{inputs.toolchain}}
+      run: |
+        if [[ -f "rust-toolchain" || -f "rust-toolchain.toml" ]]
+        then
+          # Install the toolchain as specified in the file
+          # Might break at some point: https://github.com/rust-lang/rustup/issues/1397
+          rustup show
+        else
+          rustup toolchain install ${{inputs.toolchain}}${{steps.flags.outputs.targets}}${{steps.flags.outputs.components}} --profile minimal${{steps.flags.outputs.downgrade}} --no-self-update
+          rustup default ${{inputs.toolchain}}
+        fi
+      shell: bash
+
+    - name: Print installed versions
+      id: versions
+      run: |
+        echo "::set-output name=rustc-version::$(rustc --version)"
+        rustc --version --verbose
+        echo "::set-output name=cargo-version::$(cargo --version)"
+        cargo --version --verbose
+        echo "::set-output name=rustup-version::$(rustup --version)"
+        rustup --version
+
+        DATE=$(rustc --version --verbose | sed -ne 's/^commit-date: \(20[0-9][0-9]\)-\([01][0-9]\)-\([0-3][0-9]\)$/\1\2\3/p')
+        HASH=$(rustc --version --verbose | sed -ne 's/^commit-hash: //p')
+        echo "::set-output name=cachekey::$(echo $DATE$HASH | head -c12)"
+      shell: bash
+
+    - name: "Setup Rust Caching"
+      uses: Swatinem/rust-cache@v2