cp: manages target with trailing '/'

src/uu/cp/src/copydir.rs

@@ -17,7 +17,9 @@ use std::path::{Path, PathBuf, StripPrefixError};
 use indicatif::ProgressBar;
 use uucore::display::Quotable;
 use uucore::error::UIoError;
-use uucore::fs::{canonicalize, FileInformation, MissingHandling, ResolveMode};
+use uucore::fs::{
+    canonicalize, path_ends_with_terminator, FileInformation, MissingHandling, ResolveMode,
+};
 use uucore::show;
 use uucore::show_error;
 use uucore::uio_error;
@@ -170,7 +172,14 @@ impl Entry {
         let mut descendant =
             get_local_to_root_parent(&source_absolute, context.root_parent.as_deref())?;
         if no_target_dir {
-            descendant = descendant.strip_prefix(context.root)?.to_path_buf();
+            let source_is_dir: bool = direntry.path().is_dir();
+            if path_ends_with_terminator(context.target) && source_is_dir {
+                if let Err(e) = std::fs::create_dir_all(context.target) {
+                    eprintln!("Failed to create directory: {}", e);
+                }
+            } else {
+                descendant = descendant.strip_prefix(context.root)?.to_path_buf();
+            }
         }
 
         let local_to_target = context.target.join(descendant);

src/uu/cp/src/cp.rs

@@ -32,8 +32,8 @@ use platform::copy_on_write;
 use uucore::display::Quotable;
 use uucore::error::{set_exit_code, UClapError, UError, UResult, UUsageError};
 use uucore::fs::{
-    are_hardlinks_to_same_file, canonicalize, is_symlink_loop, paths_refer_to_same_file,
-    FileInformation, MissingHandling, ResolveMode,
+    are_hardlinks_to_same_file, canonicalize, is_symlink_loop, path_ends_with_terminator,
+    paths_refer_to_same_file, FileInformation, MissingHandling, ResolveMode,
 };
 use uucore::{backup_control, update_control};
 // These are exposed for projects (e.g. nushell) that want to create an `Options` value, which
@@ -1994,6 +1994,10 @@ fn copy_helper(
         fs::create_dir_all(parent)?;
     }
 
+    if path_ends_with_terminator(dest) && !dest.is_dir() {
+        return Err(Error::NotADirectory(dest.to_path_buf()));
+    }
+
     if source.as_os_str() == "/dev/null" {
         /* workaround a limitation of fs::copy
          * https://github.com/rust-lang/rust/issues/79390