From e75d4f8a100af4cf2a8c09ed29c56f345ce454a7 Mon Sep 17 00:00:00 2001
From: Logic769 <tiancongyu769@outlook.com>
Date: Fri, 30 Oct 2026 03:36:25 +0800
Subject: [PATCH 1/3] nl: accept negative values for -v and -i

---
 src/uu/nl/src/nl.rs      | 2 ++
 tests/by-util/test_nl.rs | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/src/uu/nl/src/nl.rs b/src/uu/nl/src/nl.rs
index 3f58e77cdff..ec69895fc23 100644
--- a/src/uu/nl/src/nl.rs
+++ b/src/uu/nl/src/nl.rs
@@ -353,6 +353,7 @@ pub fn uu_app() -> Command {
                 .long(options::LINE_INCREMENT)
                 .help(translate!("nl-help-line-increment"))
                 .value_name("NUMBER")
+                .allow_negative_numbers(true)
                 .value_parser(clap::value_parser!(i64)),
         )
         .arg(
@@ -392,6 +393,7 @@ pub fn uu_app() -> Command {
                 .long(options::STARTING_LINE_NUMBER)
                 .help(translate!("nl-help-starting-line-number"))
                 .value_name("NUMBER")
+                .allow_negative_numbers(true)
                 .value_parser(clap::value_parser!(i64)),
         )
         .arg(
diff --git a/tests/by-util/test_nl.rs b/tests/by-util/test_nl.rs
index d63a1790c0a..cee8cdb27a1 100644
--- a/tests/by-util/test_nl.rs
+++ b/tests/by-util/test_nl.rs
@@ -1039,3 +1039,12 @@ fn test_other_numeric_options_still_reject_values_above_the_limit() {
             .stderr_contains("invalid value '18446744073709551616'");
     }
 }
+
+#[test]
+fn test_negative_starting_line_and_increment() {
+    new_ucmd!()
+        .args(&["-v", "-1"])
+        .pipe_in("a\nb\n")
+        .succeeds()
+        .stdout_is("    -1\ta\n     0\tb\n");
+}

From 906c09873abedba8a090cf773163a3cd357ddd5c Mon Sep 17 00:00:00 2001
From: Logic769 <tiancongyu769@outlook.com>
Date: Fri, 30 Oct 2026 21:10:30 +0800
Subject: [PATCH 2/3] nl: cover a negative increment given as a separate
 argument

---
 tests/by-util/test_nl.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tests/by-util/test_nl.rs b/tests/by-util/test_nl.rs
index cee8cdb27a1..17557c4bf38 100644
--- a/tests/by-util/test_nl.rs
+++ b/tests/by-util/test_nl.rs
@@ -1048,3 +1048,14 @@ fn test_negative_starting_line_and_increment() {
         .succeeds()
         .stdout_is("    -1\ta\n     0\tb\n");
 }
+
+#[test]
+fn test_negative_line_increment_as_a_separate_argument() {
+    for arg in ["-i", "--line-increment"] {
+        new_ucmd!()
+            .args(&[arg, "-1"])
+            .pipe_in("a\nb\nc\n")
+            .succeeds()
+            .stdout_is("     1\ta\n     0\tb\n    -1\tc\n");
+    }
+}

From 4c480a981434e93aa8d53a4e60ac045fbd7994e0 Mon Sep 17 00:00:00 2001
From: Logic769 <tiancongyu769@outlook.com>
Date: Mon, 2 Nov 2026 13:29:20 +0800
Subject: [PATCH 3/3] test(nl): cover negative starting line as a separate
 argument

---
 tests/by-util/test_nl.rs | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/tests/by-util/test_nl.rs b/tests/by-util/test_nl.rs
index 17557c4bf38..fd27723ba00 100644
--- a/tests/by-util/test_nl.rs
+++ b/tests/by-util/test_nl.rs
@@ -1041,12 +1041,14 @@ fn test_other_numeric_options_still_reject_values_above_the_limit() {
 }
 
 #[test]
-fn test_negative_starting_line_and_increment() {
-    new_ucmd!()
-        .args(&["-v", "-1"])
-        .pipe_in("a\nb\n")
-        .succeeds()
-        .stdout_is("    -1\ta\n     0\tb\n");
+fn test_negative_starting_line_as_a_separate_argument() {
+    for arg in ["-v", "--starting-line-number"] {
+        new_ucmd!()
+            .args(&[arg, "-1"])
+            .pipe_in("a\nb\n")
+            .succeeds()
+            .stdout_is("    -1\ta\n     0\tb\n");
+    }
 }
 
 #[test]