minorbug(cp): io error messages vague when using -g

src/uu/cp/src/cp.rs

@@ -835,12 +835,22 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let (sources, target) = parse_path_args(paths, &options)?;
 
     if let Err(error) = copy(&sources, &target, &options) {
-        if let CpError::NotAllFilesCopied = error {
-            // Error::NotAllFilesCopied is non-fatal, but the error
-            // code should still be EXIT_ERR as does GNU cp
-        } else {
-            // Else we caught a fatal bubbled-up error, log it to stderr
-            show_error!("{error}");
+        match error {
+            CpError::NotAllFilesCopied => {
+                // non-fatal; exit code still EXIT_ERR
+            }
+            CpError::IoErr(io_err) if io_err.kind() == io::ErrorKind::NotFound => {
+                show_error!(
+                    "{}",
+                    translate!(
+                        "cp-error-cannot-stat",
+                        "source" => format!("'{}'", sources[0].display())
+                    )
+                );
+            }
+            _ => {
+                show_error!("{error}");
+            }
         }
         set_exit_code(EXIT_ERR);
     }

tests/by-util/test_cp.rs

@@ -8067,3 +8067,13 @@ fn test_cp_p_preserves_posix_acls() {
         "cp -p must preserve POSIX ACLs (GNU tests/cp/acl regression)",
     );
 }
+
+#[test]
+fn test_progressbar_inexistent_source() {
+    let (_, mut ucmd) = at_and_ucmd!();
+    ucmd.arg("-g")
+        .arg("inexistent1")
+        .arg("inexistent2")
+        .fails_with_code(1)
+        .stderr_contains("cp: cannot stat 'inexistent1': No such file or directory");
+}