Added fuzzer in Litmusctl (litmuschaos#210)

Signed-off-by: Saranya-jena <[email protected]>

pkg/utils/common.go

@@ -123,6 +123,9 @@ func PrintInYamlFormat(inf interface{}) {
 }
 
 func GenerateRandomString(n int) (string, error) {
+	if n <= 0 {
+		return "", fmt.Errorf("length should not be negative")
+	}
 	const letters = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-"
 	ret := make([]byte, n)
 	for i := 0; i < n; i++ {

pkg/utils/testdata/fuzz/FuzzGenerateRandomString/db3c85722c184874f5c5f7a0dc70931623063a57537f3add9bea423066303259

@@ -0,0 +1,2 @@
+go test fuzz v1
+int(-82)

pkg/utils/utils_fuzz_test.go

@@ -0,0 +1,41 @@
+package utils
+
+import (
+	"strings"
+	"testing"
+)
+
+func isValidString(s string) bool {
+	// Define the set of valid characters
+	validChars := "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-"
+
+	// Iterate over each character in the string
+	for _, char := range s {
+		// Check if the character is not in the set of valid characters
+		if !strings.ContainsRune(validChars, char) {
+			return false
+		}
+	}
+	return true
+}
+
+func FuzzGenerateRandomString(f *testing.F) {
+	f.Add(10)
+	f.Fuzz(func(t *testing.T, n int) {
+		randomString, err := GenerateRandomString(n)
+		if err != nil && n > 0 {
+			t.Errorf("Error generating random string: %v", err)
+		}
+		// Perform checks on the generated string
+		// Check if the length matches the expected length
+		if n >= 0 && len(randomString) != n {
+			t.Errorf("Generated string length doesn't match expected length")
+		}
+
+		// Check if the string contains only valid characters
+		if !isValidString(randomString) {
+			t.Errorf("Generated string contains invalid characters")
+		}
+	})
+
+}