Add ISBN-10 to ISBN-13 validation and conversion

Enhance NormalizeISBN to validate and convert ISBNs: - Validate length (10 or 13 digits), return error if invalid - Convert ISBN-10 to ISBN-13 by prefixing '978' and recalculating checksum - Add NormalizeISBNSafe for backward compatibility in scanners This ensures all ISBNs stored in database are valid ISBN-13 format.
2026-02-11 09:42:18 -05:00
parent 0eee34ad01
commit 0f8db2ab07
6 changed files with 226 additions and 20 deletions
@@ -0,0 +1,118 @@
+package utils
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNormalizeISBN_Validation(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		expected    string
+		expectError bool
+	}{
+		{
+			name:        "valid ISBN-13",
+			input:       "978-0-306-40615-7",
+			expected:    "9780306406157",
+			expectError: false,
+		},
+		{
+			name:        "valid ISBN-10 converts to ISBN-13",
+			input:       "0-306-40615-2",
+			expected:    "9780306406157",
+			expectError: false,
+		},
+		{
+			name:        "ISBN-10 with X converts to ISBN-13",
+			input:       "0-596-00965-X",
+			expected:    "9780596009656",
+			expectError: false,
+		},
+		{
+			name:        "empty string",
+			input:       "",
+			expected:    "",
+			expectError: false,
+		},
+		{
+			name:        "11 digits - invalid",
+			input:       "97801234567",
+			expected:    "",
+			expectError: true,
+		},
+		{
+			name:        "12 digits - invalid",
+			input:       "978012345678",
+			expected:    "",
+			expectError: true,
+		},
+		{
+			name:        "14 digits - invalid",
+			input:       "97801234567890",
+			expected:    "",
+			expectError: true,
+		},
+		{
+			name:        "only hyphens",
+			input:       "---",
+			expected:    "",
+			expectError: true,
+		},
+		{
+			name:        "only text",
+			input:       "not-an-isbn",
+			expected:    "",
+			expectError: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result, err := NormalizeISBN(tt.input)
+
+			if tt.expectError {
+				require.Error(t, err)
+				assert.Equal(t, "", result)
+			} else {
+				require.NoError(t, err)
+				assert.Equal(t, tt.expected, result)
+			}
+		})
+	}
+}
+
+func TestConvertISBN10To13(t *testing.T) {
+	tests := []struct {
+		name     string
+		isbn10   string
+		expected string
+	}{
+		{
+			name:     "ISBN-10 0-306-40615-2",
+			isbn10:   "0306406152",
+			expected: "9780306406157",
+		},
+		{
+			name:     "ISBN-10 0-596-00965-X (X checksum)",
+			isbn10:   "059600965X",
+			expected: "9780596009656",
+		},
+		{
+			name:     "ISBN-10 0-8044-2957-X",
+			isbn10:   "080442957X",
+			expected: "9780804429573",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result, err := convertISBN10To13(tt.isbn10)
+			require.NoError(t, err)
+			assert.Equal(t, tt.expected, result)
+		})
+	}
+}