chown: show "ownership of 'foo' retained" message

* Display a message when the owner is not changed.

* Display a message when the current user/group doesn't match those specified in the `--from` args.

* print messages to stdout

* Show the message "ownership of 'foo' retained as 'bar'" for every path entry when `chown -v -R --from=`

* fix chown tests: test stdout and not stderr

* factorize duplicate code in a function

* Display a message when the owner is not changed.

* Display a message when the current user/group doesn't match those specified in the `--from` args.

* print messages to stdout

* Show the message "ownership of 'foo' retained as 'bar'" for every path entry when `chown -v -R --from=`

* fix chown tests: test stdout and not stderr

* factorize duplicate code in a function

* display the retained ownership details according to the destination ownership.

src/uucore/src/lib/features/perms.rs

@@ -271,6 +271,11 @@ impl ChownExecutor {
                 }
             }
         } else {
+            self.print_verbose_ownership_retained_as(
+                path,
+                meta.uid(),
+                self.dest_gid.map(|_| meta.gid()),
+            );
             0
         };
 
@@ -332,6 +337,11 @@ impl ChownExecutor {
             };
 
             if !self.matched(meta.uid(), meta.gid()) {
+                self.print_verbose_ownership_retained_as(
+                    path,
+                    meta.uid(),
+                    self.dest_gid.map(|_| meta.gid()),
+                );
                 continue;
             }
 
@@ -393,6 +403,35 @@ impl ChownExecutor {
             IfFrom::UserGroup(u, g) => u == uid && g == gid,
         }
     }
+
+    fn print_verbose_ownership_retained_as(&self, path: &Path, uid: u32, gid: Option<u32>) {
+        if self.verbosity.level == VerbosityLevel::Verbose {
+            match (self.dest_uid, self.dest_gid, gid) {
+                (Some(_), Some(_), Some(gid)) => {
+                    println!(
+                        "ownership of {} retained as {}:{}",
+                        path.quote(),
+                        entries::uid2usr(uid).unwrap_or_else(|_| uid.to_string()),
+                        entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
+                    );
+                }
+                (None, Some(_), Some(gid)) => {
+                    println!(
+                        "ownership of {} retained as {}",
+                        path.quote(),
+                        entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
+                    );
+                }
+                (_, _, _) => {
+                    println!(
+                        "ownership of {} retained as {}",
+                        path.quote(),
+                        entries::uid2usr(uid).unwrap_or_else(|_| uid.to_string()),
+                    );
+                }
+            }
+        }
+    }
 }
 
 pub mod options {

tests/by-util/test_chown.rs

@@ -742,3 +742,263 @@ fn test_chown_file_notexisting() {
     // TODO: uncomment once message changed from "cannot dereference" to "cannot access"
     // result.stderr_contains("cannot access 'not_existing': No such file or directory");
 }
+
+#[test]
+fn test_chown_no_change_to_user_from_user() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42")
+        .arg("43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {user_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_user_from_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=:42")
+        .arg("43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {user_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_user_from_user_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42:42")
+        .arg("43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {user_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_group_from_user() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42")
+        .arg(":43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {group_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_group_from_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=:42")
+        .arg(":43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {group_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_group_from_user_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42:42")
+        .arg(":43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!("ownership of '{file}' retained as {group_name}\n"));
+}
+
+#[test]
+fn test_chown_no_change_to_user_group_from_user() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42")
+        .arg("43:43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!(
+            "ownership of '{file}' retained as {user_name}:{group_name}\n"
+        ));
+}
+
+#[test]
+fn test_chown_no_change_to_user_group_from_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=:42")
+        .arg("43:43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!(
+            "ownership of '{file}' retained as {user_name}:{group_name}\n"
+        ));
+}
+
+#[test]
+fn test_chown_no_change_to_user_group_from_user_group() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    let result = scene.cmd("whoami").run();
+    if skipping_test_is_okay(&result, "whoami: cannot find name for user ID") {
+        return;
+    }
+    let user_name = String::from(result.stdout_str().trim());
+    assert!(!user_name.is_empty());
+    let result = scene.cmd("id").arg("-ng").run();
+    if skipping_test_is_okay(&result, "id: cannot find name for group ID") {
+        return;
+    }
+    let group_name = String::from(result.stdout_str().trim());
+    assert!(!group_name.is_empty());
+
+    let file = "f";
+    at.touch(file);
+    scene
+        .ucmd()
+        .arg("-v")
+        .arg("--from=42:42")
+        .arg("43:43")
+        .arg(file)
+        .succeeds()
+        .stdout_only(format!(
+            "ownership of '{file}' retained as {user_name}:{group_name}\n"
+        ));
+}