chore: add tests for misuses of NewAuthorizationHasher

Add tests for misuses of NewAuthorizationHasher and improve an error
message.

Author: gwossum

authorization/hasher_test.go

@@ -0,0 +1,45 @@
+package authorization_test
+
+import (
+	"testing"
+
+	"github.com/go-crypt/crypt/algorithm"
+	"github.com/influxdata/influxdb/v2/authorization"
+	influxdb2_algo "github.com/influxdata/influxdb/v2/pkg/crypt/algorithm/influxdb2"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_NewAuthorizationHasher_EmptyDecoderVariants(t *testing.T) {
+	hasher, err := authorization.NewAuthorizationHasher(
+		authorization.WithDecoderVariants([]influxdb2_algo.Variant{}),
+	)
+
+	require.ErrorIs(t, err, authorization.ErrNoDecoders)
+	require.Nil(t, hasher)
+}
+
+func TestNewAuthorizationHasher_WithInvalidDecoderVariant(t *testing.T) {
+	// Test that using an invalid decoder variant returns an error
+	hasher, err := authorization.NewAuthorizationHasher(
+		authorization.WithDecoderVariants([]influxdb2_algo.Variant{
+			influxdb2_algo.Variant(-1), // Invalid variant
+		}),
+	)
+
+	// Should return an error and nil hasher
+	require.ErrorIs(t, err, algorithm.ErrParameterInvalid)
+	require.Contains(t, err.Error(), "registering variant")
+	require.Nil(t, hasher)
+}
+
+func TestNewAuthorizationHasher_WithHasherVariantInvalid(t *testing.T) {
+	// Test that using VariantNone returns an error
+	hasher, err := authorization.NewAuthorizationHasher(
+		authorization.WithHasherVariant(influxdb2_algo.Variant(-1)),
+	)
+
+	// Should return an error and nil hasher
+	require.ErrorIs(t, err, algorithm.ErrParameterInvalid)
+	require.ErrorContains(t, err, "creating hasher")
+	require.Nil(t, hasher)
+}

pkg/crypt/algorithm/influxdb2/variant.go

@@ -62,7 +62,7 @@ func (v Variant) RegisterDecoder(r algorithm.DecoderRegister) error {
 	case VariantSHA512:
 		return RegisterDecoderSHA512(r)
 	default:
-		return fmt.Errorf("RegisterDecoder with invalid variant %v", v)
+		return fmt.Errorf("RegisterDecoder with invalid variant %v: %w", v, algorithm.ErrParameterInvalid)
 	}
 }