date: improve date to allow the fuzzer to pass

.github/workflows/fuzzing.yml

@@ -79,8 +79,7 @@ jobs:
       matrix:
         test-target:
           - { name: fuzz_test, should_pass: true }
-          # https://github.com/uutils/coreutils/issues/5311
-          - { name: fuzz_date, should_pass: false }
+          - { name: fuzz_date, should_pass: true }
           - { name: fuzz_expr, should_pass: true }
           - { name: fuzz_printf, should_pass: true }
           - { name: fuzz_echo, should_pass: true }

fuzz/fuzz_targets/fuzz_date.rs

@@ -3,12 +3,38 @@ use libfuzzer_sys::fuzz_target;
 
 use std::ffi::OsString;
 use uu_date::uumain;
+use uufuzz::generate_and_run_uumain;
 
 fuzz_target!(|data: &[u8]| {
     let delim: u8 = 0; // Null byte
-    let args = data
+    let fuzz_args: Vec<OsString> = data
         .split(|b| *b == delim)
         .filter_map(|e| std::str::from_utf8(e).ok())
-        .map(OsString::from);
-    uumain(args);
+        .map(OsString::from)
+        .collect();
+
+    // Skip test cases that would cause the program to read from stdin
+    // These would hang the fuzzer waiting for input
+    for i in 0..fuzz_args.len() {
+        if let Some(arg) = fuzz_args.get(i) {
+            let arg_str = arg.to_string_lossy();
+            // Skip if -f- or --file=- (reads dates from stdin)
+            if (arg_str == "-f"
+                && fuzz_args
+                    .get(i + 1)
+                    .map(|a| a.to_string_lossy() == "-")
+                    .unwrap_or(false))
+                || arg_str == "-f-"
+                || arg_str == "--file=-"
+            {
+                return;
+            }
+        }
+    }
+
+    // Add program name as first argument (required for proper argument parsing)
+    let mut args = vec![OsString::from("date")];
+    args.extend(fuzz_args);
+
+    let _ = generate_and_run_uumain(&args, uumain, None);
 });

src/uu/date/locales/en-US.ftl

@@ -104,3 +104,4 @@ date-error-date-overflow = date overflow '{$date}'
 date-error-setting-date-not-supported-macos = setting the date is not supported by macOS
 date-error-setting-date-not-supported-redox = setting the date is not supported by Redox
 date-error-cannot-set-date = cannot set date
+date-error-extra-operand = extra operand '{$operand}'

src/uu/date/locales/fr-FR.ftl

@@ -99,3 +99,4 @@ date-error-date-overflow = débordement de date '{$date}'
 date-error-setting-date-not-supported-macos = la définition de la date n'est pas prise en charge par macOS
 date-error-setting-date-not-supported-redox = la définition de la date n'est pas prise en charge par Redox
 date-error-cannot-set-date = impossible de définir la date
+date-error-extra-operand = opérande supplémentaire '{$operand}'

src/uu/date/src/date.rs

@@ -171,7 +171,39 @@ fn parse_military_timezone_with_offset(s: &str) -> Option<i32> {
 #[uucore::main]
 #[allow(clippy::cognitive_complexity)]
 pub fn uumain(args: impl uucore::Args) -> UResult<()> {
-    let matches = uucore::clap_localization::handle_clap_result(uu_app(), args)?;
+    let args: Vec<std::ffi::OsString> = args.collect();
+    let matches = match uu_app().try_get_matches_from(&args) {
+        Ok(matches) => matches,
+        Err(e) => {
+            match e.kind() {
+                clap::error::ErrorKind::DisplayHelp | clap::error::ErrorKind::DisplayVersion => {
+                    return Err(e.into());
+                }
+                _ => {
+                    // Convert unknown options to be treated as invalid date format
+                    // This ensures consistent exit status 1 instead of clap's exit status 77
+                    if let Some(arg) = args.get(1) {
+                        return Err(USimpleError::new(
+                            1,
+                            translate!("date-error-invalid-date", "date" => arg.to_string_lossy()),
+                        ));
+                    }
+                    return Err(USimpleError::new(1, e.to_string()));
+                }
+            }
+        }
+    };
+
+    // Check for extra operands (multiple positional arguments)
+    if let Some(formats) = matches.get_many::<String>(OPT_FORMAT) {
+        let format_args: Vec<&String> = formats.collect();
+        if format_args.len() > 1 {
+            return Err(USimpleError::new(
+                1,
+                translate!("date-error-extra-operand", "operand" => format_args[1]),
+            ));
+        }
+    }
 
     let format = if let Some(form) = matches.get_one::<String>(OPT_FORMAT) {
         if !form.starts_with('+') {
@@ -513,7 +545,7 @@ pub fn uu_app() -> Command {
                 .help(translate!("date-help-universal"))
                 .action(ArgAction::SetTrue),
         )
-        .arg(Arg::new(OPT_FORMAT))
+        .arg(Arg::new(OPT_FORMAT).num_args(0..).trailing_var_arg(true))
 }
 
 /// Return the appropriate format string for the given settings.

tests/by-util/test_date.rs

@@ -17,6 +17,45 @@ fn test_invalid_arg() {
     new_ucmd!().arg("--definitely-invalid").fails_with_code(1);
 }
 
+#[test]
+fn test_empty_arguments() {
+    new_ucmd!().arg("").fails_with_code(1);
+    new_ucmd!().args(&["", ""]).fails_with_code(1);
+    new_ucmd!().args(&["", "", ""]).fails_with_code(1);
+}
+
+#[test]
+fn test_extra_operands() {
+    new_ucmd!()
+        .args(&["test", "extra"])
+        .fails_with_code(1)
+        .stderr_contains("extra operand 'extra'");
+}
+
+#[test]
+fn test_invalid_long_option() {
+    new_ucmd!()
+        .arg("--fB")
+        .fails_with_code(1)
+        .stderr_contains("invalid date '--fB'");
+}
+
+#[test]
+fn test_invalid_short_option() {
+    new_ucmd!()
+        .arg("-w")
+        .fails_with_code(1)
+        .stderr_contains("invalid date '-w'");
+}
+
+#[test]
+fn test_single_dash_as_date() {
+    new_ucmd!()
+        .arg("-")
+        .fails_with_code(1)
+        .stderr_contains("invalid date");
+}
+
 #[test]
 fn test_date_email() {
     for param in ["--rfc-email", "--rfc-e", "-R", "--rfc-2822", "--rfc-822"] {