Add visibility parameters to control scope of generated extension

Tests/ResgenSwiftTests/Generate/StringsConfigurationTests.swift

@@ -0,0 +1,98 @@
+//
+//  StringsConfigurationTests.swift
+//  ResgenSwift
+//
+//  Created by Thibaut Schmitt on 18/07/2025.
+//
+
+import Foundation
+@testable import ResgenSwift
+import XCTest
+
+final class StringsConfigurationTests: XCTestCase {
+
+    let projectDirectory = "projectDirectory/"
+    
+    func test_argsGeneration_requiredArgs() {
+        // Given
+        let testingConfiguration = StringsConfiguration(
+            inputFile: "path/to/strings.txt",
+            outputPath: "Strings/Generated",
+            langs: "fr en en-us",
+            defaultLang: "en",
+            extensionOutputPath: nil, // Strings/Generated
+            extensionName: nil, // String
+            extensionSuffix: nil, // Testing
+            visibility: nil, // "internal"
+            staticMembers: nil, // true
+            xcStrings: nil // true
+        )
+
+        // When
+        let arguments = testingConfiguration.getArguments(
+            projectDirectory: projectDirectory,
+            force: false
+        )
+                
+        // Expect
+        let expectedArguments = [
+            "projectDirectory/path/to/strings.txt",
+            "--output-path",
+            "projectDirectory/Strings/Generated",
+            "--langs",
+            "fr en en-us",
+            "--default-lang",
+            "en"
+        ]
+
+        XCTAssertEqual(arguments, expectedArguments)
+    }
+    
+    func test_argsGeneration_allArguments() {
+        // Given
+        let testingConfiguration = StringsConfiguration(
+            inputFile: "path/to/strings.txt",
+            outputPath: "Strings/Generated",
+            langs: "fr en en-us",
+            defaultLang: "en",
+            extensionOutputPath: "Strings/Generated",
+            extensionName: "AppString",
+            extensionSuffix: "Testing",
+            visibility: "internal",
+            staticMembers: true,
+            xcStrings: true
+        )
+
+        // When
+        let arguments = testingConfiguration.getArguments(
+            projectDirectory: projectDirectory,
+            force: true
+        )
+
+        // Expect
+        let expectedArguments = [
+            "-f",
+            "projectDirectory/path/to/strings.txt",
+            "--output-path",
+            "projectDirectory/Strings/Generated",
+            "--langs",
+            "fr en en-us",
+            "--default-lang",
+            "en",
+            "--extension-output-path",
+            "projectDirectory/Strings/Generated",
+            "--extension-name",
+            "AppString",
+            "--extension-suffix",
+            "Testing",
+            "--visibility",
+            "internal",
+            "--xc-strings",
+            "true",
+            "--static-members",
+            "true"
+        ]
+
+        XCTAssertEqual(arguments, expectedArguments)
+    }
+}