From 01ac6dfd186e380b848bfea56ae8e8b8485d53ab Mon Sep 17 00:00:00 2001
From: Will Shuttleworth <willshuttle21@gmail.com>
Date: Mon, 16 Jun 2025 03:45:11 -0400
Subject: [PATCH] Merge pull request #8135 from
 willshuttleworth/stty-set-undefined

stty: fix mappings with empty string literal args
---
 src/uu/stty/src/stty.rs    |  2 +-
 tests/by-util/test_stty.rs | 38 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/src/uu/stty/src/stty.rs b/src/uu/stty/src/stty.rs
index e6ed38d2a..7866ecaad 100644
--- a/src/uu/stty/src/stty.rs
+++ b/src/uu/stty/src/stty.rs
@@ -598,7 +598,7 @@ fn apply_char_mapping(termios: &mut Termios, mapping: &(SpecialCharacterIndices,
 //
 // This function returns the ascii value of valid control chars, or ControlCharMappingError if invalid
 fn string_to_control_char(s: &str) -> Result<u8, ControlCharMappingError> {
-    if s == "undef" || s == "^-" {
+    if s == "undef" || s == "^-" || s.is_empty() {
         return Ok(0);
     }
 
diff --git a/tests/by-util/test_stty.rs b/tests/by-util/test_stty.rs
index 997336281..864888fc2 100644
--- a/tests/by-util/test_stty.rs
+++ b/tests/by-util/test_stty.rs
@@ -22,11 +22,11 @@ fn runs() {
 #[test]
 #[ignore = "Fails because cargo test does not run in a tty"]
 fn print_all() {
-    let res = new_ucmd!().succeeds();
+    let res = new_ucmd!().args(&["--all"]).succeeds();
 
     // Random selection of flags to check for
     for flag in [
-        "parenb", "parmrk", "ixany", "iuclc", "onlcr", "ofdel", "icanon", "noflsh",
+        "parenb", "parmrk", "ixany", "onlcr", "ofdel", "icanon", "noflsh",
     ] {
         res.stdout_contains(flag);
     }
@@ -167,3 +167,37 @@ fn invalid_baud_setting() {
         .fails()
         .stderr_contains("invalid ospeed '995'");
 }
+
+#[test]
+#[ignore = "Fails because cargo test does not run in a tty"]
+fn set_mapping() {
+    new_ucmd!().args(&["intr", "'"]).succeeds();
+    new_ucmd!()
+        .args(&["--all"])
+        .succeeds()
+        .stdout_contains("intr = '");
+
+    new_ucmd!().args(&["intr", "undef"]).succeeds();
+    new_ucmd!()
+        .args(&["--all"])
+        .succeeds()
+        .stdout_contains("intr = <undef>");
+
+    new_ucmd!().args(&["intr", "^-"]).succeeds();
+    new_ucmd!()
+        .args(&["--all"])
+        .succeeds()
+        .stdout_contains("intr = <undef>");
+
+    new_ucmd!().args(&["intr", ""]).succeeds();
+    new_ucmd!()
+        .args(&["--all"])
+        .succeeds()
+        .stdout_contains("intr = <undef>");
+
+    new_ucmd!().args(&["intr", "^C"]).succeeds();
+    new_ucmd!()
+        .args(&["--all"])
+        .succeeds()
+        .stdout_contains("intr = ^C");
+}