bug(chmod): chmod on symlink pointing to non existing file is failing (#1694)

src/uu/chmod/src/chmod.rs

@@ -182,7 +182,17 @@ impl Chmoder {
             Ok(meta) => meta.mode() & 0o7777,
             Err(err) => {
                 if !self.quiet {
-                    show_error!("{}", err);
+                    if is_symlink(file) {
+                        if self.verbose {
+                            show_info!(
+                                "neither symbolic link '{}' nor referent has been changed",
+                                file.display()
+                            );
+                        }
+                        return Ok(());
+                    } else {
+                        show_error!("{}: '{}'", err, file.display());
+                    }
                 }
                 return Err(1);
             }
@@ -260,3 +270,10 @@ impl Chmoder {
         }
     }
 }
+
+pub fn is_symlink<P: AsRef<Path>>(path: P) -> bool {
+    match fs::symlink_metadata(path) {
+        Ok(m) => m.file_type().is_symlink(),
+        Err(_) => false,
+    }
+}

tests/by-util/test_chmod.rs

@@ -346,3 +346,31 @@ fn test_chmod_preserve_root() {
         .stderr
         .contains("chmod: error: it is dangerous to operate recursively on '/'"));
 }
+
+#[test]
+fn test_chmod_symlink_non_existing_file() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    at.symlink_file("/non-existing", "test-long.link");
+
+    let result = ucmd
+        .arg("-R")
+        .arg("755")
+        .arg("-v")
+        .arg("test-long.link")
+        .fails();
+}
+
+#[test]
+fn test_chmod_symlink_non_existing_recursive() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    at.mkdir("tmp");
+    at.symlink_file("/non-existing", "tmp/test-long.link");
+
+    let result = ucmd.arg("-R").arg("755").arg("-v").arg("tmp").succeeds();
+    // it should be a success
+    println!("stderr {}", result.stderr);
+    println!("stdout {}", result.stdout);
+    assert!(result
+        .stderr
+        .contains("neither symbolic link 'tmp/test-long.link' nor referent has been changed"));
+}