Fix install: invalid link at destination

also remove some FixMEs for FreeBsd

src/uu/install/src/install.rs

@@ -748,6 +748,18 @@ fn perform_backup(to: &Path, b: &Behavior) -> UResult<Option<PathBuf>> {
 /// Returns an empty Result or an error in case of failure.
 ///
 fn copy_file(from: &Path, to: &Path) -> UResult<()> {
+    // fs::copy fails if destination is a invalid symlink.
+    // so lets just remove all existing files at destination before copy.
+    if let Err(e) = fs::remove_file(to) {
+        if e.kind() != std::io::ErrorKind::NotFound {
+            show_error!(
+                "Failed to remove existing file {}. Error: {:?}",
+                to.display(),
+                e
+            );
+        }
+    }
+
     if from.as_os_str() == "/dev/null" {
         /* workaround a limitation of fs::copy
          * https://github.com/rust-lang/rust/issues/79390

tests/by-util/test_install.rs

@@ -8,7 +8,7 @@ use crate::common::util::{is_ci, run_ucmd_as_root, TestScenario};
 use filetime::FileTime;
 use std::fs;
 use std::os::unix::fs::{MetadataExt, PermissionsExt};
-#[cfg(not(any(windows, target_os = "freebsd")))]
+#[cfg(not(windows))]
 use std::process::Command;
 #[cfg(any(target_os = "linux", target_os = "android"))]
 use std::thread::sleep;
@@ -610,13 +610,17 @@ fn test_install_copy_then_compare_file_with_extra_mode() {
 }
 
 const STRIP_TARGET_FILE: &str = "helloworld_installed";
-#[cfg(not(any(windows, target_os = "freebsd")))]
+#[cfg(all(not(windows), not(target_os = "freebsd")))]
 const SYMBOL_DUMP_PROGRAM: &str = "objdump";
-#[cfg(not(any(windows, target_os = "freebsd")))]
+#[cfg(target_os = "freebsd")]
+const SYMBOL_DUMP_PROGRAM: &str = "llvm-objdump";
+#[cfg(not(windows))]
 const STRIP_SOURCE_FILE_SYMBOL: &str = "main";
 
 fn strip_source_file() -> &'static str {
-    if cfg!(target_os = "macos") {
+    if cfg!(target_os = "freebsd") {
+        "helloworld_freebsd"
+    } else if cfg!(target_os = "macos") {
         "helloworld_macos"
     } else if cfg!(target_arch = "arm") || cfg!(target_arch = "aarch64") {
         "helloworld_android"
@@ -626,8 +630,7 @@ fn strip_source_file() -> &'static str {
 }
 
 #[test]
-// FixME: Freebsd fails on 'No such file or directory'
-#[cfg(not(any(windows, target_os = "freebsd")))]
+#[cfg(not(windows))]
 fn test_install_and_strip() {
     let scene = TestScenario::new(util_name!());
     let at = &scene.fixtures;
@@ -650,8 +653,7 @@ fn test_install_and_strip() {
 }
 
 #[test]
-// FixME: Freebsd fails on 'No such file or directory'
-#[cfg(not(any(windows, target_os = "freebsd")))]
+#[cfg(not(windows))]
 fn test_install_and_strip_with_program() {
     let scene = TestScenario::new(util_name!());
     let at = &scene.fixtures;
@@ -677,8 +679,6 @@ fn test_install_and_strip_with_program() {
 
 #[cfg(all(unix, feature = "chmod"))]
 #[test]
-// FixME: Freebsd fails on 'No such file or directory'
-#[cfg(not(target_os = "freebsd"))]
 fn test_install_and_strip_with_program_hyphen() {
     let scene = TestScenario::new(util_name!());
 
@@ -715,6 +715,64 @@ fn test_install_and_strip_with_program_hyphen() {
         .stdout_is("./-dest\n");
 }
 
+#[cfg(all(unix, feature = "chmod"))]
+#[test]
+fn test_install_on_invalid_link_at_destination() {
+    let scene = TestScenario::new(util_name!());
+
+    let at = &scene.fixtures;
+    at.mkdir("src");
+    at.mkdir("dest");
+    let src_dir = at.plus("src");
+    let dst_dir = at.plus("dest");
+
+    at.touch("test.sh");
+    at.symlink_file(
+        "/opt/FakeDestination",
+        &dst_dir.join("test.sh").to_string_lossy(),
+    );
+    scene.ccmd("chmod").arg("+x").arg("test.sh").succeeds();
+    at.symlink_file("test.sh", &src_dir.join("test.sh").to_string_lossy());
+
+    scene
+        .ucmd()
+        .current_dir(&src_dir)
+        .arg(src_dir.join("test.sh"))
+        .arg(dst_dir.join("test.sh"))
+        .succeeds()
+        .no_stderr()
+        .no_stdout();
+}
+
+#[cfg(all(unix, feature = "chmod"))]
+#[test]
+fn test_install_on_invalid_link_at_destination_and_dev_null_at_source() {
+    let scene = TestScenario::new(util_name!());
+
+    let at = &scene.fixtures;
+    at.mkdir("src");
+    at.mkdir("dest");
+    let src_dir = at.plus("src");
+    let dst_dir = at.plus("dest");
+
+    at.touch("test.sh");
+    at.symlink_file(
+        "/opt/FakeDestination",
+        &dst_dir.join("test.sh").to_string_lossy(),
+    );
+    scene.ccmd("chmod").arg("+x").arg("test.sh").succeeds();
+    at.symlink_file("test.sh", &src_dir.join("test.sh").to_string_lossy());
+
+    scene
+        .ucmd()
+        .current_dir(&src_dir)
+        .arg("/dev/null")
+        .arg(dst_dir.join("test.sh"))
+        .succeeds()
+        .no_stderr()
+        .no_stdout();
+}
+
 #[test]
 #[cfg(not(windows))]
 fn test_install_and_strip_with_invalid_program() {