parallelize CI (#11)

Author: TDHolmes

.github/workflows/rust.yml

@@ -11,7 +11,7 @@ env:
   CARGO_TERM_COLOR: always
 
 jobs:
-  build:
+  msrv:
 
     runs-on: ubuntu-latest
 
@@ -21,13 +21,23 @@ jobs:
       with:
         profile: minimal
         toolchain: nightly
-        override: true
         target: thumbv7em-none-eabihf
-        components: clippy, rustfmt
 
     - name: Checkout Sources
       uses: actions/checkout@v2
 
+    - name: Cache Cargo Dependencies
+      uses: actions/cache@v2
+      with:
+        path: |
+          - ~/.cargo/bin/
+          - ~/.cargo/registry/index/
+          - ~/.cargo/registry/cache/
+          - ~/.cargo/git/db/
+        key: ${{ runner.OS }}-cargo-msrv-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.OS }}-cargo-msrv
+
     - name: install cargo-msrv
       uses: actions-rs/install@v0.1
       with:
@@ -42,21 +52,90 @@ jobs:
         cargo msrv --verify --path ./ep-systick -- cargo check
         cargo msrv --verify --path ./ep-dwt -- cargo check
 
-    - name: Check Formatting
-      run: cargo fmt --check
+  build:
+
+    runs-on: ubuntu-latest
+    env:
+      CARGO_BUILD_TARGET: thumbv7em-none-eabihf
+      RUSTFLAGS: -D warnings
+
+    steps:
+    - name: Install Rust (thumbv7em)
+      uses: actions-rs/toolchain@v1
+      with:
+        profile: minimal
+        toolchain: nightly
+        override: true
+        target: thumbv7em-none-eabihf
+
+    - name: Checkout Sources
+      uses: actions/checkout@v2
+
+    - name: Cache Cargo Dependencies
+      uses: actions/cache@v2
+      with:
+        path: |
+          - ~/.cargo/bin/
+          - ~/.cargo/registry/index/
+          - ~/.cargo/registry/cache/
+          - ~/.cargo/git/db/
+        key: ${{ runner.OS }}-cargo-build-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.OS }}-cargo-build
+
+    - name: Cache Build Output Dependencies
+      uses: actions/cache@v2
+      with:
+        path: target
+        key: ${{ runner.OS }}-build-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.OS }}-build-
 
     - name: Build (default)
-      env:
-        CARGO_BUILD_TARGET: thumbv7em-none-eabihf
-        RUSTFLAGS: -D warnings
       run: cargo build
 
     - name: Build (all features)
-      env:
-        CARGO_BUILD_TARGET: thumbv7em-none-eabihf
-        RUSTFLAGS: -D warnings
       run: cargo build --all-features
 
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Install Rust (thumbv7em)
+      uses: actions-rs/toolchain@v1
+      with:
+        profile: minimal
+        toolchain: nightly
+        override: true
+        target: thumbv7em-none-eabihf
+        components: clippy, rustfmt
+
+    - name: Checkout Sources
+      uses: actions/checkout@v2
+
+    - name: Cache Cargo Dependencies
+      uses: actions/cache@v2
+      with:
+        path: |
+          - ~/.cargo/bin/
+          - ~/.cargo/registry/index/
+          - ~/.cargo/registry/cache/
+          - ~/.cargo/git/db/
+        key: ${{ runner.OS }}-cargo-test-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.OS }}-cargo-test
+
+    - name: Cache Build Output Dependencies
+      uses: actions/cache@v2
+      with:
+        path: target
+        key: ${{ runner.OS }}-test-${{ hashFiles('**/Cargo.lock') }}
+        restore-keys: |
+          ${{ runner.OS }}-test
+
+    - name: Check Formatting
+      run: cargo fmt --check
+
     - name: test all crates
       env:
         RUSTFLAGS: -D warnings