uucore: use single quotes for shell-quoted names containing '!'

src/uucore/src/lib/features/quoting_style/mod.rs

@@ -1217,6 +1217,16 @@ mod tests {
                 ("'can'\\''\\t'", "shell-escape-always"),
             ],
         );
+
+        check_names_both(
+            "can'!t",
+            &[
+                ("'can'\\''!t'", "shell"),
+                ("'can'\\''!t'", "shell-always"),
+                ("'can'\\''!t'", "shell-escape"),
+                ("'can'\\''!t'", "shell-escape-always"),
+            ],
+        );
     }
 
     #[test]

src/uucore/src/lib/features/quoting_style/shell_quoter.rs

@@ -247,7 +247,7 @@ fn bytes_start_with(bytes: &[u8], pattern: &[u8]) -> bool {
 /// Return a set of characters that implies quoting of the word in
 /// shell-quoting mode.
 fn shell_escaped_char_set(is_dirname: bool) -> &'static [u8] {
-    const ESCAPED_CHARS: &[u8] = b":\"`$\\^\n\t\r=";
+    const ESCAPED_CHARS: &[u8] = b":\"`$\\^\n\t\r=!";
     // the ':' colon character only induce quoting in the
     // context of ls displaying a directory name before listing its content.
     // (e.g. with the recursive flag -R)
@@ -299,6 +299,22 @@ mod tests {
             (ShellQuotes::Double, true)
         );
 
+        // Simple quote uses double quotes in non-escape mode
+        assert_eq!(
+            initial_quoting(b"a'b", false, false, false),
+            (ShellQuotes::Double, true)
+        );
+
+        // `!` is history-expanded inside double quotes, so a quote with `!` uses single quotes
+        assert_eq!(
+            initial_quoting(b"a'!b", false, false, true),
+            (ShellQuotes::Single, true)
+        );
+        assert_eq!(
+            initial_quoting(b"a'!b", false, false, false),
+            (ShellQuotes::Single, true)
+        );
+
         // Shell special chars force single quotes in escape mode
         assert_eq!(
             initial_quoting(b"test$var", false, false, true),

tests/by-util/test_ls.rs

@@ -3080,6 +3080,24 @@ mod quoting {
         );
     }
 
+    #[test]
+    fn test_ls_quoting_single_quote_exclamation() {
+        check_quoting_dirname(
+            "dir'!name",
+            &[
+                ("shell", "'dir'\\''!name'", "'./dir'\\''!name'"),
+                ("shell-always", "'dir'\\''!name'", "'./dir'\\''!name'"),
+                ("shell-escape", "'dir'\\''!name'", "'./dir'\\''!name'"),
+                (
+                    "shell-escape-always",
+                    "'dir'\\''!name'",
+                    "'./dir'\\''!name'",
+                ),
+            ],
+            &[],
+        );
+    }
+
     #[test]
     fn test_ls_quoting_double_quote() {
         check_quoting_dirname(

tests/by-util/test_printf.rs

@@ -20,6 +20,7 @@ use uutests::new_ucmd;
 #[case::sub_q_string_non_printable(&["non-printable: %q", "\"$test\""], "non-printable: '\"$test\"'")]
 #[case::sub_q_string_special_non_printable(&["non-printable: %q", "test~"], "non-printable: test~")]
 #[case::sub_q_string_empty(&["%q", ""], "''")]
+#[case::sub_q_string_quote_and_bang(&["%q", "a'!b"], "'a'\\''!b'")]
 #[case::sub_char(&["the letter %c", "A"], "the letter A")]
 #[case::sub_char_from_string(&["%c%c%c", "five", "%", "oval"], "f%o")]
 #[case::sub_num_int(&["twenty is %i", "20"], "twenty is 20")]