From 003975841b4886b4559411d3122fe7587c195657 Mon Sep 17 00:00:00 2001
From: Przemek Delewski <pdelewski@users.noreply.github.com>
Date: Thu, 29 Dec 2022 14:40:39 +0100
Subject: [PATCH] extract checkargs

---
 instrgen/driver/driver_test.go |  8 ++++++++
 instrgen/driver/main.go        | 16 ++++++++++++----
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/instrgen/driver/driver_test.go b/instrgen/driver/driver_test.go
index 37572cae290..1cb0bb2ecb2 100644
--- a/instrgen/driver/driver_test.go
+++ b/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)
diff --git a/instrgen/driver/main.go b/instrgen/driver/main.go
index bbb85b452b0..b9844c8a148 100644
--- a/instrgen/driver/main.go
+++ b/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)
 	}