touch: Respect -h when getting metadata (#5951)

* Add tests that stat symlinks

* Check follow first in stat

* Don't run tests on FreeBSD

It would be possible to get them to run on FreeBSD by avoiding
get_symlink_times, but the behavior we're testing is not
platform-specific, so it's fine to not test it on FreeBSD.

---------

Co-authored-by: Sylvestre Ledru <sylvestre@debian.org>

src/uu/touch/src/touch.rs

@@ -326,12 +326,12 @@ fn update_times(
 // If `follow` is `true`, the function will try to follow symlinks
 // If `follow` is `false` or the symlink is broken, the function will return metadata of the symlink itself
 fn stat(path: &Path, follow: bool) -> UResult<(FileTime, FileTime)> {
-    let metadata = match fs::metadata(path) {
-        Ok(metadata) => metadata,
-        Err(e) if e.kind() == std::io::ErrorKind::NotFound && !follow => fs::symlink_metadata(path)
-            .map_err_context(|| format!("failed to get attributes of {}", path.quote()))?,
-        Err(e) => return Err(e.into()),
-    };
+    let metadata = if follow {
+        fs::metadata(path).or_else(|_| fs::symlink_metadata(path))
+    } else {
+        fs::symlink_metadata(path)
+    }
+    .map_err_context(|| format!("failed to get attributes of {}", path.quote()))?;
 
     Ok((
         FileTime::from_last_access_time(&metadata),

tests/by-util/test_touch.rs

@@ -5,7 +5,7 @@
 // spell-checker:ignore (formats) cymdhm cymdhms mdhm mdhms ymdhm ymdhms datetime mktime
 
 use crate::common::util::{AtPath, TestScenario};
-use filetime::FileTime;
+use filetime::{self, set_symlink_file_times, FileTime};
 use std::fs::remove_file;
 use std::path::PathBuf;
 
@@ -854,3 +854,40 @@ fn test_touch_invalid_date_format() {
         .fails()
         .stderr_contains("touch: invalid date format '+1000000000000 years'");
 }
+
+#[test]
+#[cfg(not(target_os = "freebsd"))]
+fn test_touch_symlink_with_no_deref() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    let target = "foo.txt";
+    let symlink = "bar.txt";
+    let time = FileTime::from_unix_time(123, 0);
+
+    at.touch(target);
+    at.relative_symlink_file(target, symlink);
+    set_symlink_file_times(at.plus(symlink), time, time).unwrap();
+
+    ucmd.args(&["-a", "--no-dereference", symlink]).succeeds();
+    // Modification time shouldn't be set to the destination's modification time
+    assert_eq!(time, get_symlink_times(&at, symlink).1);
+}
+
+#[test]
+#[cfg(not(target_os = "freebsd"))]
+fn test_touch_reference_symlink_with_no_deref() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    let target = "foo.txt";
+    let symlink = "bar.txt";
+    let arg = "baz.txt";
+    let time = FileTime::from_unix_time(123, 0);
+
+    at.touch(target);
+    at.relative_symlink_file(target, symlink);
+    set_symlink_file_times(at.plus(symlink), time, time).unwrap();
+    at.touch(arg);
+
+    ucmd.args(&["--reference", symlink, "--no-dereference", arg])
+        .succeeds();
+    // Times should be taken from the symlink, not the destination
+    assert_eq!((time, time), get_symlink_times(&at, arg));
+}