context: copy symlinks as symlinks and improve error messages

src/context/mod.rs

@@ -147,4 +147,37 @@ mod tests {
             "subcontent"
         );
     }
+
+    /// Copying a tree containing a dangling symlink must reproduce the link
+    /// itself rather than failing to follow it (which previously surfaced as
+    /// a bare "No such file or directory (os error 2)").
+    #[test]
+    fn test_context_copy_preserves_dangling_symlink() {
+        use std::os::unix::fs::symlink;
+        let temp_dir = tempfile::tempdir().unwrap();
+        let ctx = Context::new(ContextConfig::Local);
+
+        let src_dir = temp_dir.path().join("src");
+        std::fs::create_dir_all(&src_dir).unwrap();
+        // A regular file alongside the symlink, to ensure normal copies still work.
+        std::fs::write(src_dir.join("real.txt"), "data").unwrap();
+        // A dangling symlink pointing to a non-existent target.
+        symlink("/nonexistent/target", src_dir.join("dangling")).unwrap();
+
+        let dest_dir = temp_dir.path().join("dest");
+        ctx.copy_path(&src_dir, &dest_dir).unwrap();
+
+        // The regular file was copied.
+        assert_eq!(
+            ctx.read_file(&dest_dir.join("real.txt")).unwrap(),
+            "data"
+        );
+        // The symlink was reproduced as a symlink (not followed).
+        let meta = std::fs::symlink_metadata(dest_dir.join("dangling")).unwrap();
+        assert!(meta.file_type().is_symlink());
+        assert_eq!(
+            std::fs::read_link(dest_dir.join("dangling")).unwrap(),
+            std::path::Path::new("/nonexistent/target")
+        );
+    }
 }