Minor --file-name code hygeine

src/bin/bat/app.rs

@@ -136,10 +136,11 @@ impl App {
             }
         });
 
-        if self.matches.value_of("file-name").is_some()
-            && self.matches.values_of("file-name").unwrap().len() != files.len()
-        {
-            return Err("When using --file-name, each input file must have a corresponding --file-name specified.".into());
+        match self.matches.values_of("file-name") {
+            Some(filenames) if filenames.len() != files.len() => {
+                return Err(format!("{} {}", filenames.len(), files.len()).into());
+            }
+            _ => {}
         }
 
         Ok(Config {

src/controller.rs

@@ -45,20 +45,12 @@ impl<'b> Controller<'b> {
 
         let stdin = io::stdin();
 
-        let filenames = if self.config.filenames.is_none() {
-            vec![None; self.config.files.len()]
-        } else {
-            self.config
-                .filenames
-                .as_ref()
-                .unwrap()
-                .into_iter()
-                .map(|name| Some(*name))
-                .collect()
+        let filenames: Box<dyn Iterator<Item = _>> = match self.config.filenames {
+            Some(ref filenames) => Box::new(filenames.into_iter().map(|name| Some(*name))),
+            None => Box::new(std::iter::repeat(None)),
         };
 
-        for it in self.config.files.iter().zip(filenames) {
-            let (input_file, file_name) = it;
+        for (input_file, file_name) in self.config.files.iter().zip(filenames) {
             match input_file.get_reader(&stdin) {
                 Err(error) => {
                     handle_error(&error);