extract checkargs

instrgen/driver/driver_test.go

@@ -96,6 +96,14 @@ func TestCommands(t *testing.T) {
 	require.NoError(t, err)
 }
 
+func TestArgs(t *testing.T) {
+	err := checkArgs(nil)
+	require.Error(t, err)
+	args := []string{"driver", "--inject", "", "./..."}
+	err = checkArgs(args)
+	require.NoError(t, err)
+}
+
 func TestUnknown(t *testing.T) {
 	err := executeCommand("unknown", "a", "b")
 	require.Error(t, err)

instrgen/driver/main.go

@@ -129,13 +129,21 @@ func executeCommand(command string, projectPath string, packagePattern string) e
 	return errors.New("unknown command")
 }
 
+func checkArgs(args []string) error {
+	if len(args) != 4 {
+		_ = usage()
+		return errors.New("wrong arguments")
+	}
+	return nil
+}
+
 func main() {
 	fmt.Println("autotel compiler")
-	if len(os.Args) != 4 {
-		_ = usage()
-		os.Exit(-1)
+	err := checkArgs(os.Args)
+	if err != nil {
+		return
 	}
-	err := executeCommand(os.Args[1], os.Args[2], os.Args[3])
+	err = executeCommand(os.Args[1], os.Args[2], os.Args[3])
 	if err != nil {
 		log.Fatal(err)
 	}

instrgen/driver/testdata/interface/go.mod

@@ -4,14 +4,12 @@ go 1.18
 
 replace go.opentelemetry.io/contrib/instrgen => ../../..
 
-require (
-	go.opentelemetry.io/contrib/instrgen v0.0.0-20221228173227-92e0588b124b
-	go.opentelemetry.io/otel v1.11.2
-)
+require go.opentelemetry.io/contrib/instrgen v0.0.0-20221228173227-92e0588b124b
 
 require (
 	github.com/go-logr/logr v1.2.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
+	go.opentelemetry.io/otel v1.11.2 // indirect
 	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.11.2 // indirect
 	go.opentelemetry.io/otel/sdk v1.11.2 // indirect
 	go.opentelemetry.io/otel/trace v1.11.2 // indirect