Lint and check formatting (#6)

.github/workflows/ci.yml

@@ -16,6 +16,7 @@ jobs:
       - uses: actions/setup-go@v4
         with:
           go-version: "1.18"
+      - uses: golangci/golangci-lint-action@v3
       - run: go build -v ./...
       - run: go test -v -race -coverprofile=coverage.txt -covermode=atomic ./...
       - uses: codecov/codecov-action@v3

.golangci.yml

@@ -0,0 +1,4 @@
+linters:
+  enable:
+    - gofmt
+    - gocritic

cmd/root.go

@@ -18,8 +18,8 @@ var rootCmd = &cobra.Command{
 	Short: "Combine your contributors avatars into a single image",
 	Run: func(cmd *cobra.Command, args []string) {
 		f, err := os.Create("montage.png")
-		defer f.Close()
 		onError(err)
+		defer f.Close()
 		client, err := api.DefaultRESTClient()
 		onError(err)
 		repository, err := repository.Current()

pkg/usersource/usersource.go

@@ -8,7 +8,7 @@ type User struct {
 	// AvatarURL is the URL of the user's avatar.
 	AvatarURL string `json:"avatar_url"`
 	// Type is either "User" or "Bot".
-	Type    string `json:"type"`
+	Type string `json:"type"`
 }
 
 // UserSource provides a utility to iterate over users.