From 7c24ede827dcd0221ca80d2644283810f83b7fd7 Mon Sep 17 00:00:00 2001
From: Wondr <wondr.design@gmail.com>
Date: Fri, 5 Jun 2026 03:08:16 +0100
Subject: [PATCH 1/2] grep: handle zero-width matches at EOF

---
 src/matcher.rs     |  2 ++
 tests/test_grep.rs | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/src/matcher.rs b/src/matcher.rs
index 6d72b69..cb61884 100644
--- a/src/matcher.rs
+++ b/src/matcher.rs
@@ -209,6 +209,8 @@ struct Cursor<'a> {
 
 impl Cursor<'_> {
     fn refill(&mut self) {
+        // Searching at EOF is still meaningful for zero-width patterns such as
+        // `$` and `x*`. After emitting one, `offset` is nudged past EOF below.
         if self.offset > self.line.len() {
             self.pending = None;
             return;
diff --git a/tests/test_grep.rs b/tests/test_grep.rs
index 2c16db4..e01dd1b 100644
--- a/tests/test_grep.rs
+++ b/tests/test_grep.rs
@@ -587,6 +587,23 @@ fn only_matching() {
         .succeeds()
         .stdout_only("Hello\nhELLO\nHELLO\n");
 
+    // Zero-width matches do not print in -o mode, but still mark the line as
+    // matched. This matters for -v because matched lines must not be selected.
+    let (_s, mut c) = ucmd();
+    c.args(&["-o", "$"]).pipe_in("\n").succeeds().no_output();
+
+    let (_s, mut c) = ucmd();
+    c.args(&["-o", "-v", "$"])
+        .pipe_in("a\n\nb\n")
+        .fails_with_code(1)
+        .no_output();
+
+    let (_s, mut c) = ucmd();
+    c.args(&["-o", "-v", "x*"])
+        .pipe_in("a\n\nb\n")
+        .fails_with_code(1)
+        .no_output();
+
     // After a match ends, ^ must not re-match at that position.
     let (_s, mut c) = ucmd();
     c.args(&["-o", "^hello*"])

From 5ea366761347e01fa0bac3531885bdd610f9aa66 Mon Sep 17 00:00:00 2001
From: Wondr <wondr.design@gmail.com>
Date: Fri, 5 Jun 2026 15:41:15 +0100
Subject: [PATCH 2/2] grep: narrow zero-width EOF PR to coverage

---
 src/matcher.rs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/matcher.rs b/src/matcher.rs
index cb61884..6d72b69 100644
--- a/src/matcher.rs
+++ b/src/matcher.rs
@@ -209,8 +209,6 @@ struct Cursor<'a> {
 
 impl Cursor<'_> {
     fn refill(&mut self) {
-        // Searching at EOF is still meaningful for zero-width patterns such as
-        // `$` and `x*`. After emitting one, `offset` is nudged past EOF below.
         if self.offset > self.line.len() {
             self.pending = None;
             return;