code coverage (#12)

.github/workflows/ci.yml

@@ -1,9 +1,9 @@
 name: ci
 
-on:   
+on:
   pull_request:
     types: [opened, synchronize, reopened, ready_for_review]
-    
+
   push:
     branches:
       - "main"
@@ -15,15 +15,17 @@ jobs:
   ci:
     if: github.event.pull_request.draft == false
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go-version: ["1.19.x", "1.20.x", "1.21.x"]
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v3
 
-      - name: Set up Go
+      - name: Set up Go ${{ matrix.go-version }}
         uses: actions/setup-go@v3
         with:
-          go-version: '1.19.x'
-          # go-version-file: './go.mod'
+          go-version: ${{ matrix.go-version }}
           cache: true
 
       - name: Build
@@ -32,5 +34,7 @@ jobs:
       - name: Test
         run: go test -v ./... -race -covermode=atomic -coverprofile=coverage.out
 
-      - name: Upload coverage to Codecov
+      - name: Upload coverage reports to Codecov
         uses: codecov/codecov-action@v3
+        env:
+          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}