Addresses #246

Some implementation to search by filetype `executables`

src/app.rs

@@ -83,7 +83,7 @@ pub fn build_app() -> App<'static, 'static> {
                 .number_of_values(1)
                 .takes_value(true)
                 .value_name("filetype")
-                .possible_values(&["f", "file", "d", "directory", "l", "symlink"])
+                .possible_values(&["f", "file", "d", "directory", "l", "symlink", "x", "executable"])
                 .hide_possible_values(true),
         )
         .arg(
@@ -189,7 +189,8 @@ fn usage() -> HashMap<&'static str, Help> {
         , "Filter the search by type (multiple allowable filetypes can be specified):\n  \
              'f' or 'file':         regular files\n  \
              'd' or 'directory':    directories\n  \
-             'l' or 'symlink':      symbolic links");
+             'l' or 'symlink':      symbolic links\n  \
+             'x' or 'executable':   executables");
     doc!(h, "extension"
         , "Filter by file extension"
         , "(Additionally) filter search results by their file extension. Multiple allowable file \

src/internal.rs

@@ -22,6 +22,7 @@ pub struct FileTypes {
     pub files: bool,
     pub directories: bool,
     pub symlinks: bool,
+    pub executables: bool,
 }
 
 impl Default for FileTypes {
@@ -30,6 +31,7 @@ impl Default for FileTypes {
             files: false,
             directories: false,
             symlinks: false,
+            executables: false,
         }
     }
 }

src/main.rs

@@ -161,6 +161,7 @@ fn main() {
                     "f" | "file" => file_types.files = true,
                     "d" | "directory" => file_types.directories = true,
                     "l" | "symlink" => file_types.symlinks = true,
+                    "x" | "executable" => file_types.executables = true,
                     _ => unreachable!(),
                 }
             }

src/output.rs

@@ -135,11 +135,11 @@ fn get_path_style<'a>(path: &Path, ls_colors: &'a LsColors) -> Option<&'a ansi_t
 }
 
 #[cfg(any(unix, target_os = "redox"))]
-fn is_executable(md: &fs::Metadata) -> bool {
+pub fn is_executable(md: &fs::Metadata) -> bool {
     md.permissions().mode() & 0o111 != 0
 }
 
 #[cfg(windows)]
-fn is_executable(_: &fs::Metadata) -> bool {
+pub fn is_executable(_: &fs::Metadata) -> bool {
     false
 }

src/walk.rs

@@ -201,6 +201,7 @@ pub fn scan(path_vec: &[PathBuf], pattern: Arc<Regex>, config: Arc<FdOptions>) {
                     if (entry_type.is_file() && !file_types.files)
                         || (entry_type.is_dir() && !file_types.directories)
                         || (entry_type.is_symlink() && !file_types.symlinks)
+                        || (output::is_executable(&entry.metadata().unwrap()) && !file_types.executables)
                     {
                         return ignore::WalkState::Continue;
                     } else if !(entry_type.is_file() || entry_type.is_dir()