Check error returns to satisfy errcheck lint

main.go

@@ -55,8 +55,8 @@ func main() {
 // non-nil error on any failure.
 func run(args []string, out io.Writer) error {
 	if len(args) == 2 && (args[1] == "-v" || args[1] == "--version") {
-		fmt.Fprintf(out, "encapic %s\n", version)
-		return nil
+		_, err := fmt.Fprintf(out, "encapic %s\n", version)
+		return err
 	}
 	if len(args) != 2 {
 		return fmt.Errorf("usage: %s <certname>", args[0])
@@ -95,7 +95,7 @@ func fetch(baseURL, certname string) ([]byte, error) {
 	if err != nil {
 		return nil, fmt.Errorf("request %s: %w", url, err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {

main_test.go

@@ -92,7 +92,7 @@ func TestFetchTimeout(t *testing.T) {
 	client := &http.Client{Timeout: 20 * time.Millisecond}
 	resp, err := client.Get(srv.URL + "/cblr/svc/op/puppet/hostname/host.example")
 	if err == nil {
-		resp.Body.Close()
+		_ = resp.Body.Close()
 		t.Fatalf("expected timeout error, got none")
 	}
 }
@@ -119,7 +119,9 @@ func TestRunVersion(t *testing.T) {
 
 func TestDefaultBaseURLCompiledIn(t *testing.T) {
 	// Guard against accidental changes to the in-cluster default.
-	os.Unsetenv("ENCAPI_URL")
+	if err := os.Unsetenv("ENCAPI_URL"); err != nil {
+		t.Fatalf("unsetenv: %v", err)
+	}
 	if defaultBaseURL != "http://encapi.encapi.svc.cluster.local" {
 		t.Errorf("defaultBaseURL = %q", defaultBaseURL)
 	}