test: 13 Integration-Tests hinzugefügt + .gitignore optimiert

Integration-Tests:
- test_help_flag, test_version_flag
- test_dry_run_no_changes, test_actual_rename
- test_hidden_files_preserved, test_hidden_file_with_spaces
- test_umlaut_conversion, test_double_extension
- test_exclude_pattern, test_quiet_mode
- test_multiple_paths, test_parentheses_removed
- test_special_identifiers_preserved

.gitignore:
- Besser organisiert (Kategorien)
- Cargo.lock hinzugefügt
- Temporäre Dateien (*.tmp, *.log, *.bak)
- OS-spezifische Dateien (Thumbs.db)
- Test-Artefakte

Gesamt: 22 Tests (9 Unit + 13 Integration)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

tests/integration_tests.rs

@@ -0,0 +1,194 @@
+use assert_cmd::assert::OutputAssertExt;
+use assert_cmd::cargo::CommandCargoExt;
+use predicates::prelude::*;
+use std::fs;
+use std::process::Command;
+use tempfile::TempDir;
+
+#[test]
+fn test_help_flag() {
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg("--help");
+    cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("Usage: ntu"));
+}
+
+#[test]
+fn test_version_flag() {
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg("--version");
+    cmd.assert()
+        .success()
+        .stdout(predicate::str::contains("NameToUnix"));
+}
+
+#[test]
+fn test_dry_run_no_changes() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("test file.txt");
+    fs::write(&file_path, "test content").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg("--dry-run").arg(temp_dir.path());
+    cmd.assert().success();
+
+    // File should still have spaces (not renamed)
+    assert!(file_path.exists());
+    assert!(!temp_dir.path().join("test_file.txt").exists());
+}
+
+#[test]
+fn test_actual_rename() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("test file.txt");
+    fs::write(&file_path, "test content").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // File should be renamed
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join("test_file.txt").exists());
+}
+
+#[test]
+fn test_hidden_files_preserved() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join(".gitignore");
+    fs::write(&file_path, "*.tmp").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // Hidden file should not be renamed
+    assert!(file_path.exists());
+}
+
+#[test]
+fn test_hidden_file_with_spaces() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join(".my config");
+    fs::write(&file_path, "config content").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // Hidden file should be renamed but keep leading dot
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join(".my_config").exists());
+}
+
+#[test]
+fn test_umlaut_conversion() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("Müller.txt");
+    fs::write(&file_path, "test").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // Umlaut should be converted
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join("Mueller.txt").exists());
+}
+
+#[test]
+fn test_double_extension() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("my archive.tar.gz");
+    fs::write(&file_path, "archive").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // Should keep .tar.gz intact
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join("my_archive.tar.gz").exists());
+}
+
+#[test]
+fn test_exclude_pattern() {
+    let temp_dir = TempDir::new().unwrap();
+    let file1 = temp_dir.path().join("test file.txt");
+    let file2 = temp_dir.path().join("test file.tmp");
+    fs::write(&file1, "test1").unwrap();
+    fs::write(&file2, "test2").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg("--exclude")
+        .arg("*.tmp")
+        .arg(temp_dir.path());
+    cmd.assert().success();
+
+    // .txt should be renamed, .tmp should not
+    assert!(!file1.exists());
+    assert!(temp_dir.path().join("test_file.txt").exists());
+    assert!(file2.exists()); // Excluded
+}
+
+#[test]
+fn test_quiet_mode() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("test file.txt");
+    fs::write(&file_path, "test").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg("--quiet").arg(temp_dir.path());
+    cmd.assert()
+        .success()
+        .stdout(predicate::str::is_empty());
+}
+
+#[test]
+fn test_multiple_paths() {
+    let temp_dir1 = TempDir::new().unwrap();
+    let temp_dir2 = TempDir::new().unwrap();
+    let file1 = temp_dir1.path().join("file 1.txt");
+    let file2 = temp_dir2.path().join("file 2.txt");
+    fs::write(&file1, "test1").unwrap();
+    fs::write(&file2, "test2").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir1.path()).arg(temp_dir2.path());
+    cmd.assert().success();
+
+    // Both files should be renamed
+    assert!(temp_dir1.path().join("file_1.txt").exists());
+    assert!(temp_dir2.path().join("file_2.txt").exists());
+}
+
+#[test]
+fn test_parentheses_removed() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("Document (1).txt");
+    fs::write(&file_path, "test").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // Parentheses should be replaced with underscores
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join("Document_1.txt").exists());
+}
+
+#[test]
+fn test_special_identifiers_preserved() {
+    let temp_dir = TempDir::new().unwrap();
+    let file_path = temp_dir.path().join("C++ Guide.pdf");
+    fs::write(&file_path, "test").unwrap();
+
+    let mut cmd = Command::cargo_bin("ntu").unwrap();
+    cmd.arg(temp_dir.path());
+    cmd.assert().success();
+
+    // C++ should be preserved
+    assert!(!file_path.exists());
+    assert!(temp_dir.path().join("C++_Guide.pdf").exists());
+}