chcon: allow overriding between --dereference and --no-dereference

src/uu/chcon/src/chcon.rs

@@ -163,7 +163,7 @@ pub fn uu_app() -> Command {
         .arg(
             Arg::new(options::dereference::DEREFERENCE)
                 .long(options::dereference::DEREFERENCE)
-                .conflicts_with(options::dereference::NO_DEREFERENCE)
+                .overrides_with(options::dereference::NO_DEREFERENCE)
                 .help(
                     "Affect the referent of each symbolic link (this is the default), \
                      rather than the symbolic link itself.",

tests/by-util/test_chcon.rs

@@ -88,6 +88,33 @@ fn valid_context_on_valid_symlink() {
     assert_eq!(get_file_context(dir.plus("a.tmp")).unwrap(), a_context);
 }
 
+#[test]
+fn valid_context_on_valid_symlink_override_dereference() {
+    let (dir, mut cmd) = at_and_ucmd!();
+    dir.touch("a.tmp");
+    dir.symlink_file("a.tmp", "la.tmp");
+
+    let a_context = get_file_context(dir.plus("a.tmp")).unwrap();
+    let la_context = get_file_context(dir.plus("la.tmp")).unwrap();
+    let new_a_context = "guest_u:object_r:etc_t:s0:c42";
+    assert_ne!(a_context.as_deref(), Some(new_a_context));
+    assert_ne!(la_context.as_deref(), Some(new_a_context));
+
+    cmd.args(&[
+        "--verbose",
+        "--no-dereference",
+        "--dereference",
+        new_a_context,
+    ])
+    .arg(dir.plus("la.tmp"))
+    .succeeds();
+    assert_eq!(
+        get_file_context(dir.plus("a.tmp")).unwrap().as_deref(),
+        Some(new_a_context)
+    );
+    assert_eq!(get_file_context(dir.plus("la.tmp")).unwrap(), la_context);
+}
+
 #[test]
 fn valid_context_on_broken_symlink() {
     let (dir, mut cmd) = at_and_ucmd!();
@@ -104,6 +131,29 @@ fn valid_context_on_broken_symlink() {
     );
 }
 
+#[test]
+fn valid_context_on_broken_symlink_after_deref() {
+    let (dir, mut cmd) = at_and_ucmd!();
+    dir.symlink_file("a.tmp", "la.tmp");
+
+    let la_context = get_file_context(dir.plus("la.tmp")).unwrap();
+    let new_la_context = "guest_u:object_r:etc_t:s0:c42";
+    assert_ne!(la_context.as_deref(), Some(new_la_context));
+
+    cmd.args(&[
+        "--verbose",
+        "--dereference",
+        "--no-dereference",
+        new_la_context,
+    ])
+    .arg(dir.plus("la.tmp"))
+    .succeeds();
+    assert_eq!(
+        get_file_context(dir.plus("la.tmp")).unwrap().as_deref(),
+        Some(new_la_context)
+    );
+}
+
 #[test]
 fn valid_context_with_prior_xattributes() {
     let (dir, mut cmd) = at_and_ucmd!();