tests: fix flaky ls tests that depend on filesystem directory order

The tests test_f_flag_disables_sorting, test_big_u_overrides_f_sort, and test_f_overrides_sort_flags made incorrect assumptions that unsorted directory order would always differ from sorted order. However, fs::read_dir() returns entries in filesystem-dependent order which may accidentally match sorted order on some filesystems. Changes: - Removed assertions comparing unsorted vs sorted outputs - Added deterministic checks (e.g., verifying --sort after -f works) - Added explicit order verification for size-sorted outputs - Tests now verify flag precedence without relying on directory order Fixes CI failures on Windows and SELinux platforms. Quality checks passed: - cargo fmt --check: ✓ - cargo clippy --test tests: ✓ - all 3 modified tests pass: ✓

Author: naoNao89

tests/by-util/test_ls.rs

@@ -6331,43 +6331,54 @@ fn test_f_flag_enables_all() {
 
 #[test]
 fn test_f_flag_disables_sorting() {
- // Test that -f disables sorting by comparing with -a (sorted) and -U (unsorted)
- // We compare outputs instead of relying on filesystem directory order
+ // Test that -f disables sorting by verifying it matches -U behavior
+ // and that explicitly sorting after -f works (proving sorting was disabled)
  let scene = TestScenario::new(util_name!());
  let at = &scene.fixtures;
  at.touch("zebra");
  at.touch("apple");
  at.touch("banana");
 
  // Get outputs with different flags
- let out_a = scene
+ let out_f = scene
  .ucmd()
+ .arg("-f")
+ .arg("-1")
+ .succeeds()
+ .stdout_move_str();
+ let out_u_all = scene
+ .ucmd()
+ .arg("-U")
  .arg("-a")
  .arg("-1")
  .succeeds()
  .stdout_move_str();
- let out_f = scene
+
+ // Test that explicit sorting after -f works (proves -f disabled sorting)
+ let out_f_then_sort = scene
  .ucmd()
  .arg("-f")
+ .arg("--sort=name")
  .arg("-1")
  .succeeds()
  .stdout_move_str();
- let out_u_all = scene
+
+ // Get sorted output for comparison
+ let out_sorted = scene
  .ucmd()
- .arg("-U")
  .arg("-a")
  .arg("-1")
  .succeeds()
  .stdout_move_str();
 
- // -f output should differ from sorted -a output (proves sorting is disabled)
- assert_ne!(
- out_a, out_f,
- "-f should produce different order than sorted -a"
- );
-
  // -f output should match -U output (both use directory order)
  assert_eq!(out_f, out_u_all, "-f should match unsorted -U behavior");
+
+ // Explicit --sort after -f should enable sorting
+ assert_eq!(
+ out_f_then_sort, out_sorted,
+ "--sort after -f should enable sorting"
+ );
 }
 
 #[test]
@@ -6508,10 +6519,6 @@ fn test_f_overrides_sort_flags() {
  out_s_f, out_u,
  "-f should win: output should match unsorted -U"
  );
- assert_ne!(
- out_s_f, out_s,
- "-f should win: output should differ from sorted -S"
- );
 }
 
 #[test]
@@ -6570,19 +6577,24 @@ fn test_big_u_overrides_f_sort() {
  "-S should win: output should be size-sorted"
  );
 
- // -S then -U: -U wins, should be unsorted
+ // -S then -U: -U wins, should match plain -U output
  let out_s_u = scene
  .ucmd()
  .arg("-S")
  .arg("-U")
  .arg("-1")
  .succeeds()
  .stdout_move_str();
- assert_eq!(out_s_u, out_u, "-U should win: output should be unsorted");
- assert_ne!(
- out_s_u, out_s,
- "-U should win: output should differ from sorted -S"
+ assert_eq!(
+ out_s_u, out_u,
+ "-U should win: output should match plain -U"
  );
+
+ // Verify size-sorted output is in correct order (this is deterministic)
+ let lines: Vec<&str> = out_s.lines().collect();
+ assert_eq!(lines[0], "large.txt", "First file should be largest");
+ assert_eq!(lines[1], "medium.txt", "Second file should be medium");
+ assert_eq!(lines[2], "small.txt", "Third file should be smallest");
 }
 
 #[test]