cp: set status code when encountering circular symbolic links

src/uu/cp/src/copydir.rs

@@ -22,7 +22,6 @@ use uucore::fs::{
     FileInformation, MissingHandling, ResolveMode, canonicalize, path_ends_with_terminator,
 };
 use uucore::show;
-use uucore::show_error;
 use uucore::translate;
 use uucore::uio_error;
 use walkdir::{DirEntry, WalkDir};
@@ -513,7 +512,7 @@ pub(crate) fn copy_directory(
             }
 
             // Print an error message, but continue traversing the directory.
-            Err(e) => show_error!("{e}"),
+            Err(e) => show!(CpError::WalkDirErr(e)),
         }
     }
 

tests/by-util/test_cp.rs

@@ -7383,3 +7383,26 @@ fn test_cp_recurse_verbose_output_with_symlink_already_exists() {
         .no_stderr()
         .stdout_is(output);
 }
+
+#[test]
+fn test_cp_circular_symbolic_links_in_directory() {
+    let source_dir = "source_dir";
+    let target_dir = "target_dir";
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    at.mkdir(source_dir);
+    at.symlink_file(
+        format!("{source_dir}/a").as_str(),
+        format!("{source_dir}/b").as_str(),
+    );
+    at.symlink_file(
+        format!("{source_dir}/b").as_str(),
+        format!("{source_dir}/a").as_str(),
+    );
+
+    ucmd.arg(source_dir)
+        .arg(target_dir)
+        .arg("-rL")
+        .fails_with_code(1)
+        .stderr_contains("Too many levels of symbolic links");
+}