From 95ccc54d05892db5630e1a9413474041605fe2f0 Mon Sep 17 00:00:00 2001
From: Daniel Hofstetter <daniel.hofstetter@42dh.com>
Date: Sat, 30 Sep 2023 15:35:05 +0200
Subject: [PATCH] nl: defer showing "line number overflow" error

---
 src/uu/nl/src/nl.rs      | 17 ++++++++++-------
 tests/by-util/test_nl.rs | 16 ++++++++++++++++
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/src/uu/nl/src/nl.rs b/src/uu/nl/src/nl.rs
index ea37e00dc..71b4aac28 100644
--- a/src/uu/nl/src/nl.rs
+++ b/src/uu/nl/src/nl.rs
@@ -56,14 +56,14 @@ impl Default for Settings {
 }
 
 struct Stats {
-    line_number: i64,
+    line_number: Option<i64>,
     consecutive_empty_lines: u64,
 }
 
 impl Stats {
     fn new(starting_line_number: i64) -> Self {
         Self {
-            line_number: starting_line_number,
+            line_number: Some(starting_line_number),
             consecutive_empty_lines: 0,
         }
     }
@@ -344,7 +344,7 @@ fn nl<T: Read>(reader: &mut BufReader<T>, stats: &mut Stats, settings: &Settings
         if let Some(new_style) = new_numbering_style {
             current_numbering_style = new_style;
             if settings.renumber {
-                stats.line_number = settings.starting_line_number;
+                stats.line_number = Some(settings.starting_line_number);
             }
             println!();
         } else {
@@ -364,18 +364,21 @@ fn nl<T: Read>(reader: &mut BufReader<T>, stats: &mut Stats, settings: &Settings
             };
 
             if is_line_numbered {
+                let Some(line_number) = stats.line_number else {
+                    return Err(USimpleError::new(1, "line number overflow"));
+                };
                 println!(
                     "{}{}{}",
                     settings
                         .number_format
-                        .format(stats.line_number, settings.number_width),
+                        .format(line_number, settings.number_width),
                     settings.number_separator,
                     line
                 );
                 // update line number for the potential next line
-                match stats.line_number.checked_add(settings.line_increment) {
-                    Some(new_line_number) => stats.line_number = new_line_number,
-                    None => return Err(USimpleError::new(1, "line number overflow")),
+                match line_number.checked_add(settings.line_increment) {
+                    Some(new_line_number) => stats.line_number = Some(new_line_number),
+                    None => stats.line_number = None, // overflow
                 }
             } else {
                 let spaces = " ".repeat(settings.number_width + 1);
diff --git a/tests/by-util/test_nl.rs b/tests/by-util/test_nl.rs
index 87f218166..78c8975a8 100644
--- a/tests/by-util/test_nl.rs
+++ b/tests/by-util/test_nl.rs
@@ -539,6 +539,22 @@ fn test_line_number_overflow() {
         .stderr_is("nl: line number overflow\n");
 }
 
+#[test]
+fn test_line_number_no_overflow() {
+    new_ucmd!()
+        .arg(format!("--starting-line-number={}", i64::MAX))
+        .pipe_in("a\n\\:\\:\nb")
+        .succeeds()
+        .stdout_is(format!("{0}\ta\n\n{0}\tb\n", i64::MAX));
+
+    new_ucmd!()
+        .arg(format!("--starting-line-number={}", i64::MIN))
+        .arg("--line-increment=-1")
+        .pipe_in("a\n\\:\\:\nb")
+        .succeeds()
+        .stdout_is(format!("{0}\ta\n\n{0}\tb\n", i64::MIN));
+}
+
 #[test]
 fn test_section_delimiter() {
     for arg in ["-dabc", "--section-delimiter=abc"] {