Use caching in actions workflow

.github/workflows/build.yml

@@ -2,18 +2,32 @@ name: Build
 on: [push, pull_request]
 jobs:
   build:
+    name: Build
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macOS-latest]
     steps:
-    - uses: actions/checkout@v1
-      with:
-        fetch-depth: 1
+    - uses: actions/checkout@v2
     - uses: actions-rs/toolchain@v1
       with:
         toolchain: stable
         override: true
+    - name: Cache Cargo registry
+      uses: actions/cache@v1
+      with:
+        path: ~/.cargo/registry
+        key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+    - name: Cache Cargo index
+      uses: actions/cache@v1
+      with:
+        path: ~/.cargo/git
+        key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
+    - name: Cache Cargo build
+      uses: actions/cache@v1
+      with:
+        path: target
+        key: ${{ runner.os }}-cargo-build-target-${{ hashFiles('**/Cargo.lock') }}
     - name: Build project
       uses: actions-rs/cargo@v1
       with:

.github/workflows/check.yml

@@ -2,11 +2,10 @@ name: Checks
 on: [pull_request]
 jobs:
   checks:
+    name: Checks
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
-      with:
-        fetch-depth: 1
+    - uses: actions/checkout@v2
     - uses: actions-rs/toolchain@v1
       with:
         toolchain: stable