uucore: use --suffix to enable backup mode (#9741)

Author: jacek-kurlit

src/uucore/src/lib/features/backup_control.rs

@@ -359,6 +359,14 @@ pub fn determine_backup_mode(matches: &ArgMatches) -> UResult<BackupMode> {
         } else {
             Ok(BackupMode::Existing)
         }
+    } else if matches.contains_id(arguments::OPT_SUFFIX) {
+        // Suffix option is enough to determine mode even if --backup is not set.
+        // If VERSION_CONTROL is not set, the default backup type is 'existing'.
+        if let Ok(method) = env::var("VERSION_CONTROL") {
+            match_method(&method, "$VERSION_CONTROL")
+        } else {
+            Ok(BackupMode::Existing)
+        }
     } else {
         // No option was present at all
         Ok(BackupMode::None)
@@ -653,6 +661,29 @@ mod tests {
         unsafe { env::remove_var(ENV_VERSION_CONTROL) };
     }
 
+    // Using --suffix without --backup defaults to --backup=existing
+    #[test]
+    fn test_backup_mode_suffix_without_backup_option() {
+        let _dummy = TEST_MUTEX.lock().unwrap();
+        let matches = make_app().get_matches_from(vec!["command", "--suffix", ".bak"]);
+
+        let result = determine_backup_mode(&matches).unwrap();
+
+        assert_eq!(result, BackupMode::Existing);
+    }
+
+    // Using --suffix without --backup uses env var if existing
+    #[test]
+    fn test_backup_mode_suffix_without_backup_option_with_env_var() {
+        let _dummy = TEST_MUTEX.lock().unwrap();
+        unsafe { env::set_var(ENV_VERSION_CONTROL, "numbered") };
+        let matches = make_app().get_matches_from(vec!["command", "--suffix", ".bak"]);
+
+        let result = determine_backup_mode(&matches).unwrap();
+
+        assert_eq!(result, BackupMode::Numbered);
+    }
+
     #[test]
     fn test_suffix_takes_hyphen_value() {
         let _dummy = TEST_MUTEX.lock().unwrap();

tests/by-util/test_cp.rs

@@ -1123,6 +1123,23 @@ fn test_cp_arg_suffix() {
     );
 }
 
+#[test]
+fn test_cp_arg_suffix_without_backup_option() {
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    ucmd.arg(TEST_HELLO_WORLD_SOURCE)
+        .arg("--suffix")
+        .arg(".bak")
+        .arg(TEST_HOW_ARE_YOU_SOURCE)
+        .succeeds();
+
+    assert_eq!(at.read(TEST_HOW_ARE_YOU_SOURCE), "Hello, World!\n");
+    assert_eq!(
+        at.read(&format!("{TEST_HOW_ARE_YOU_SOURCE}.bak")),
+        "How are you?\n"
+    );
+}
+
 #[test]
 fn test_cp_arg_suffix_hyphen_value() {
     let (at, mut ucmd) = at_and_ucmd!();

tests/by-util/test_install.rs

@@ -1231,6 +1231,30 @@ fn test_install_backup_short_custom_suffix() {
     assert!(at.file_exists(format!("{file_b}{suffix}")));
 }
 
+#[test]
+fn test_install_suffix_without_backup_option() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let file_a = "test_install_backup_custom_suffix_file_a";
+    let file_b = "test_install_backup_custom_suffix_file_b";
+    let suffix = "super-suffix-of-the-century";
+
+    at.touch(file_a);
+    at.touch(file_b);
+    scene
+        .ucmd()
+        .arg(format!("--suffix={suffix}"))
+        .arg(file_a)
+        .arg(file_b)
+        .succeeds()
+        .no_stderr();
+
+    assert!(at.file_exists(file_a));
+    assert!(at.file_exists(file_b));
+    assert!(at.file_exists(format!("{file_b}{suffix}")));
+}
+
 #[test]
 fn test_install_backup_short_custom_suffix_hyphen_value() {
     let scene = TestScenario::new(util_name!());

tests/by-util/test_ln.rs

@@ -194,6 +194,31 @@ fn test_symlink_custom_backup_suffix() {
     assert_eq!(at.resolve_link(backup), file);
 }
 
+#[test]
+fn test_symlink_suffix_without_backup_option() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    at.write("a", "a\n");
+    at.write("b", "b2\n");
+
+    assert!(at.file_exists("a"));
+    assert!(at.file_exists("b"));
+    let suffix = ".sfx";
+    let suffix_arg = &format!("--suffix={suffix}");
+    scene
+        .ucmd()
+        .args(&["-s", "-f", suffix_arg, "a", "b"])
+        .succeeds()
+        .no_stderr();
+    assert!(at.file_exists("a"));
+    assert!(at.file_exists("b"));
+    assert_eq!(at.read("a"), "a\n");
+    assert_eq!(at.read("b"), "a\n");
+    // we should have created backup for b file
+    assert_eq!(at.read(&format!("b{suffix}")), "b2\n");
+}
+
 #[test]
 fn test_symlink_custom_backup_suffix_hyphen_value() {
     let (at, mut ucmd) = at_and_ucmd!();

tests/by-util/test_mv.rs

@@ -801,6 +801,26 @@ fn test_mv_custom_backup_suffix() {
     assert!(at.file_exists(format!("{file_b}{suffix}")));
 }
 
+#[test]
+fn test_suffix_without_backup_option() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    let file_a = "test_mv_custom_backup_suffix_file_a";
+    let file_b = "test_mv_custom_backup_suffix_file_b";
+    let suffix = "super-suffix-of-the-century";
+
+    at.touch(file_a);
+    at.touch(file_b);
+    ucmd.arg(format!("--suffix={suffix}"))
+        .arg(file_a)
+        .arg(file_b)
+        .succeeds()
+        .no_stderr();
+
+    assert!(!at.file_exists(file_a));
+    assert!(at.file_exists(file_b));
+    assert!(at.file_exists(format!("{file_b}{suffix}")));
+}
+
 #[test]
 fn test_mv_custom_backup_suffix_hyphen_value() {
     let (at, mut ucmd) = at_and_ucmd!();