diff --git a/tests/by-util/test_basename.rs b/tests/by-util/test_basename.rs
index ecbfe6c5d..7ad5008b2 100644
--- a/tests/by-util/test_basename.rs
+++ b/tests/by-util/test_basename.rs
@@ -278,3 +278,21 @@ fn test_suffix_implies_multiple() {
         .succeeds()
         .stdout_is("foo\no\n");
 }
+
+#[test]
+fn test_emoji_handling() {
+    new_ucmd!()
+        .arg("/path/to/🦀.txt")
+        .succeeds()
+        .stdout_only("🦀.txt\n");
+
+    new_ucmd!()
+        .arg("/🌍/path/to/🚀.exe")
+        .succeeds()
+        .stdout_only("🚀.exe\n");
+
+    new_ucmd!()
+        .args(&["/path/to/file🎯.emoji", ".emoji"])
+        .succeeds()
+        .stdout_only("file🎯\n");
+}
diff --git a/tests/by-util/test_comm.rs b/tests/by-util/test_comm.rs
index 9c04f39c6..96a1e5497 100644
--- a/tests/by-util/test_comm.rs
+++ b/tests/by-util/test_comm.rs
@@ -587,3 +587,19 @@ fn test_comm_extra_arg_error() {
         .stderr_contains("Usage: comm [OPTION]... FILE1 FILE2")
         .stderr_contains("For more information, try '--help'.");
 }
+
+#[test]
+fn comm_emoji_sorted_inputs() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    at.write("file1", "💐\n🦀\n");
+    at.write("file2", "🦀\n🪽\n");
+
+    scene
+        .ucmd()
+        .args(&["file1", "file2"])
+        .env("LC_ALL", "C.UTF-8")
+        .succeeds()
+        .stdout_only("💐\n\t\t🦀\n\t🪽\n");
+}
diff --git a/tests/by-util/test_dirname.rs b/tests/by-util/test_dirname.rs
index 933e882d7..d5aedc45a 100644
--- a/tests/by-util/test_dirname.rs
+++ b/tests/by-util/test_dirname.rs
@@ -84,3 +84,21 @@ fn test_dirname_non_utf8_paths() {
     assert!(!output.is_empty());
     assert!(output.contains("test_"));
 }
+
+#[test]
+fn test_emoji_handling() {
+    new_ucmd!()
+        .arg("/🌍/path/to/🦀.txt")
+        .succeeds()
+        .stdout_is("/🌍/path/to\n");
+
+    new_ucmd!()
+        .arg("/🎉/path/to/🚀/")
+        .succeeds()
+        .stdout_is("/🎉/path/to\n");
+
+    new_ucmd!()
+        .args(&["-z", "/🌟/emoji/path/🦋.file"])
+        .succeeds()
+        .stdout_is("/🌟/emoji/path\u{0}");
+}
diff --git a/tests/by-util/test_echo.rs b/tests/by-util/test_echo.rs
index ab5b8b1ab..34e60e316 100644
--- a/tests/by-util/test_echo.rs
+++ b/tests/by-util/test_echo.rs
@@ -785,3 +785,21 @@ fn test_escape_sequence_ctrl_c() {
         .success()
         .stdout_only("show");
 }
+
+#[test]
+fn test_emoji_output() {
+    new_ucmd!()
+        .arg("Hello 🌍 World 🚀")
+        .succeeds()
+        .stdout_only("Hello 🌍 World 🚀\n");
+
+    new_ucmd!()
+        .args(&["-n", "Status: 🎯 Complete"])
+        .succeeds()
+        .stdout_only("Status: 🎯 Complete");
+
+    new_ucmd!()
+        .args(&["🦀", "loves", "🚀", "and", "🌟"])
+        .succeeds()
+        .stdout_only("🦀 loves 🚀 and 🌟\n");
+}
diff --git a/tests/by-util/test_env.rs b/tests/by-util/test_env.rs
index 82cec1889..b2db4a277 100644
--- a/tests/by-util/test_env.rs
+++ b/tests/by-util/test_env.rs
@@ -1755,6 +1755,17 @@ fn test_simulation_of_terminal_pty_pipes_into_data_and_sends_eot_automatically()
     std::assert_eq!(String::from_utf8_lossy(out.stderr()), "");
 }
 
+#[test]
+#[cfg(not(windows))]
+fn test_emoji_env_vars() {
+    new_ucmd!()
+        .arg("🎯_VAR=Hello 🌍")
+        .arg("printenv")
+        .arg("🎯_VAR")
+        .succeeds()
+        .stdout_contains("Hello 🌍");
+}
+
 #[cfg(unix)]
 #[test]
 fn test_simulation_of_terminal_pty_write_in_data_and_sends_eot_automatically() {
diff --git a/tests/by-util/test_expr.rs b/tests/by-util/test_expr.rs
index 729b91290..bd5e19099 100644
--- a/tests/by-util/test_expr.rs
+++ b/tests/by-util/test_expr.rs
@@ -58,6 +58,16 @@ fn test_simple_arithmetic() {
         .args(&["4", "/", "2"])
         .succeeds()
         .stdout_only("2\n");
+
+    new_ucmd!()
+        .args(&["4", "=", "2"])
+        .fails_with_code(1)
+        .stdout_only("0\n");
+
+    new_ucmd!()
+        .args(&["4", "=", "4"])
+        .succeeds()
+        .stdout_only("1\n");
 }
 
 #[test]
@@ -1927,3 +1937,32 @@ mod gnu_expr_multibyte {
         }
     }
 }
+
+#[test]
+fn test_emoji_operations() {
+    new_ucmd!()
+        .args(&["🚀", "=", "🚀"])
+        .succeeds()
+        .stdout_only("1\n");
+
+    new_ucmd!()
+        .args(&["🚀", "!=", "🚀"])
+        .fails()
+        .stdout_only("0\n");
+
+    new_ucmd!()
+        .args(&["🚀", "=", "🧨"])
+        .fails()
+        .stdout_only("0\n");
+
+    new_ucmd!()
+        .args(&["length", "🦀🚀🎯"])
+        .env("LC_ALL", "fr_FR.UTF-8")
+        .succeeds()
+        .stdout_only("3\n");
+
+    new_ucmd!()
+        .args(&["🌍", "!=", "🌎"])
+        .succeeds()
+        .stdout_only("1\n");
+}
diff --git a/tests/by-util/test_fmt.rs b/tests/by-util/test_fmt.rs
index abf2e132c..5959569de 100644
--- a/tests/by-util/test_fmt.rs
+++ b/tests/by-util/test_fmt.rs
@@ -388,3 +388,12 @@ fn test_fmt_non_utf8_paths() {
 
     ucmd.arg(&filename).succeeds();
 }
+
+#[test]
+fn fmt_reflow_unicode() {
+    new_ucmd!()
+        .args(&["-w", "4"])
+        .pipe_in("漢字漢字 💐 日本語の文字\n")
+        .succeeds()
+        .stdout_is("漢字漢字\n💐\n日本語の文字\n");
+}
diff --git a/tests/by-util/test_printf.rs b/tests/by-util/test_printf.rs
index 5e2c0c7a0..a10d5fd18 100644
--- a/tests/by-util/test_printf.rs
+++ b/tests/by-util/test_printf.rs
@@ -1453,3 +1453,11 @@ fn non_utf_8_input() {
         .fails()
         .stderr_contains("expected a numeric value");
 }
+
+#[test]
+fn test_emoji_formatting() {
+    new_ucmd!()
+        .args(&["Status: %s 🎯 Count: %d\n", "Success 🚀", "42"])
+        .succeeds()
+        .stdout_only("Status: Success 🚀 🎯 Count: 42\n");
+}
diff --git a/tests/by-util/test_tail.rs b/tests/by-util/test_tail.rs
index 1e40a2791..3f6455c21 100644
--- a/tests/by-util/test_tail.rs
+++ b/tests/by-util/test_tail.rs
@@ -4946,3 +4946,12 @@ fn test_dev_zero() {
         .succeeds()
         .stdout_only("\0");
 }
+
+#[test]
+fn tail_n_lines_with_emoji() {
+    new_ucmd!()
+        .args(&["-n", "1"])
+        .pipe_in("a\n💐\n")
+        .succeeds()
+        .stdout_only("💐\n");
+}