cp: expand target path before checking (nushell#11692)

# Description
Fixes: nushell#11683

# User-Facing Changes
NaN

# Tests + Formatting
~~I don't think we need to add a test, or else it'll copy some file to
user's directory, it seems bad.~~
Done.

# After Submitting
NaN

crates/nu-command/src/filesystem/ucp.rs

@@ -172,6 +172,8 @@ impl Command for UCp {
         let target_path = PathBuf::from(&nu_utils::strip_ansi_string_unlikely(
             target.item.to_string(),
         ));
+        let cwd = current_dir(engine_state, stack)?;
+        let target_path = nu_path::expand_path_with(&target_path, &cwd);
         if target.item.as_ref().ends_with(PATH_SEPARATOR) && !target_path.is_dir() {
             return Err(ShellError::GenericError {
                 error: "is not a directory".into(),
@@ -184,7 +186,6 @@ impl Command for UCp {
 
         // paths now contains the sources
 
-        let cwd = current_dir(engine_state, stack)?;
         let mut sources: Vec<PathBuf> = Vec::new();
 
         for mut p in paths {
@@ -227,8 +228,6 @@ impl Command for UCp {
             }
         }
 
-        let target_path = nu_path::expand_path_with(&target_path, &cwd);
-
         let attributes = make_attributes(preserve)?;
 
         let options = uu_cp::Options {

crates/nu-command/tests/commands/ucp.rs

@@ -1122,3 +1122,19 @@ fn test_cp_inside_glob_metachars_dir() {
         assert!(files_exist_at(vec!["test_file.txt"], dirs.test()));
     });
 }
+
+#[cfg(not(windows))]
+#[test]
+fn test_cp_to_customized_home_directory() {
+    Playground::setup("cp_to_home", |dirs, sandbox| {
+        std::env::set_var("HOME", dirs.test());
+        sandbox.with_files(vec![EmptyFile("test_file.txt")]);
+        let actual = nu!(cwd: dirs.test(), "mkdir test; cp test_file.txt ~/test/");
+
+        assert!(actual.err.is_empty());
+        assert!(files_exist_at(
+            vec!["test_file.txt"],
+            dirs.test().join("test")
+        ));
+    })
+}