install: warn --strip-program without -s

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

@@ -54,6 +54,7 @@ install-error-failed-to-remove = Failed to remove existing file { $path }. Error
 
 # Warning messages
 install-warning-compare-ignored = the --compare (-C) option is ignored when you specify a mode with non-permission bits
+install-warning-no-strip-with-program = WARNING: ignoring --strip-program option as -s option was not specified
 
 # Verbose output
 install-verbose-creating-directory = creating directory { $path }

src/uu/install/src/install.rs

@@ -378,6 +378,24 @@ fn behavior(matches: &ArgMatches) -> UResult<Behavior> {
     let preserve_timestamps = matches.get_flag(OPT_PRESERVE_TIMESTAMPS);
     let compare = matches.get_flag(OPT_COMPARE);
     let strip = matches.get_flag(OPT_STRIP);
+    let strip_program = match matches.get_one::<String>(OPT_STRIP_PROGRAM) {
+        Some(p) => {
+            if !strip
+                && writeln!(
+                    std::io::stderr(),
+                    "install: {}",
+                    translate!("install-warning-no-strip-with-program")
+                )
+                .is_err()
+            {
+                uucore::error::set_exit_code(1);
+            }
+            p
+        }
+        None => DEFAULT_STRIP_PROGRAM,
+    }
+    .to_string();
+
     if preserve_timestamps && compare {
         show_error!(
             "{}",
@@ -458,11 +476,7 @@ fn behavior(matches: &ArgMatches) -> UResult<Behavior> {
         preserve_timestamps,
         compare,
         strip,
-        strip_program: String::from(
-            matches
-                .get_one::<String>(OPT_STRIP_PROGRAM)
-                .map_or(DEFAULT_STRIP_PROGRAM, |s| s.as_str()),
-        ),
+        strip_program,
         create_leading: matches.get_flag(OPT_CREATE_LEADING),
         target_dir,
         no_target_dir,

tests/by-util/test_install.rs

@@ -795,6 +795,24 @@ fn test_install_and_strip() {
     assert!(!stdout.contains(STRIP_SOURCE_FILE_SYMBOL));
 }
 
+#[test]
+#[cfg(not(windows))]
+#[cfg(not(target_os = "android"))] // missing strip binary
+// FIXME test runs in a timeout with macos-latest on x86_64 in the CI
+#[cfg(not(all(target_os = "macos", target_arch = "x86_64")))]
+fn test_install_no_strip_with_program() {
+    TestScenario::new(util_name!())
+        .ucmd()
+        .arg("--strip-program")
+        .arg("true")
+        .arg(strip_source_file())
+        .arg(STRIP_TARGET_FILE)
+        .succeeds()
+        .stderr_only(
+            "install: WARNING: ignoring --strip-program option as -s option was not specified\n",
+        );
+}
+
 #[test]
 #[cfg(not(windows))]
 #[cfg(not(target_os = "android"))] // missing strip binary