cp: fix crash on -T/--no-preserve-target

src/uu/cp/src/copydir.rs

@@ -9,8 +9,9 @@
 #[cfg(windows)]
 use std::borrow::Cow;
 use std::collections::{HashMap, HashSet};
+use std::convert::identity;
 use std::env;
-use std::fs;
+use std::fs::{self, exists};
 use std::io;
 use std::path::{Path, PathBuf, StripPrefixError};
 
@@ -20,10 +21,9 @@ use uucore::error::UIoError;
 use uucore::fs::{
     FileInformation, MissingHandling, ResolveMode, canonicalize, path_ends_with_terminator,
 };
-use uucore::translate;
-
 use uucore::show;
 use uucore::show_error;
+use uucore::translate;
 use uucore::uio_error;
 use walkdir::{DirEntry, WalkDir};
 
@@ -194,15 +194,23 @@ impl Entry {
             get_local_to_root_parent(&source_absolute, context.root_parent.as_deref())?;
         if no_target_dir {
             let source_is_dir = source.is_dir();
-            if path_ends_with_terminator(context.target) && source_is_dir {
+            if path_ends_with_terminator(context.target)
+                && source_is_dir
+                && !exists(context.target).is_ok_and(identity)
+            {
                 if let Err(e) = fs::create_dir_all(context.target) {
                     eprintln!(
                         "{}",
                         translate!("cp-error-failed-to-create-directory", "error" => e)
                     );
                 }
-            } else {
-                descendant = descendant.strip_prefix(context.root)?.to_path_buf();
+            } else if let Some(stripped) = context
+                .root
+                .components()
+                .next_back()
+                .and_then(|stripped| descendant.strip_prefix(stripped).ok())
+            {
+                descendant = stripped.to_path_buf();
             }
         } else if context.root == Path::new(".") && context.target.is_dir() {
             // Special case: when copying current directory (.) to an existing directory,

tests/by-util/test_cp.rs

@@ -7090,3 +7090,49 @@ fn test_cp_recursive_files_ending_in_backslash() {
     ts.ucmd().args(&["-r", "a", "b"]).succeeds();
     assert!(at.file_exists("b/foo\\"));
 }
+
+#[test]
+fn test_cp_no_preserve_target_directory() {
+    /* Expected result:
+    ├── a
+    │   └── b
+    │       └── c
+    │           └── d
+    │               └── f1
+    ├── d
+    │   └── f1
+    └── e
+        ├── b
+        │   └── c
+        │       └── d
+        │           ├── c
+        │           │   └── d
+        │           │       └── f1
+        │           └── f1
+        ├── d
+        │   └── f1
+        ├── f2
+        └── f3
+     */
+
+    let ts = TestScenario::new(util_name!());
+    let at = &ts.fixtures;
+    at.mkdir_all("a/b/c/d");
+    at.touch("a/b/c/d/f1");
+    ts.ucmd().args(&["-rT", "a", "e"]).succeeds();
+    at.touch("e/f2");
+    ts.ucmd().args(&["-rT", "a/", "e/"]).succeeds();
+    at.touch("e/f3");
+    ts.ucmd().args(&["-rvT", "a/b/c", "e/"]).succeeds();
+    ts.ucmd().args(&["-rvT", "a/b/", "e/b/c/d/"]).succeeds();
+    ts.ucmd().args(&["-rT", "a/b/c", "."]).succeeds();
+    assert!(!at.dir_exists("e/a"));
+    assert!(at.file_exists("e/b/c/d/f1"));
+    assert!(at.file_exists("e/b/c/d/c/d/f1"));
+    assert!(!at.dir_exists("e/c"));
+    assert!(!at.dir_exists("e/c/d/b"));
+    assert!(at.file_exists("e/d/f1"));
+    assert!(at.file_exists("./d/f1"));
+    assert!(at.file_exists("e/f2"));
+    assert!(at.file_exists("e/f3"));
+}