Add completions for --language when using the fish shell.

assets/completions/bat.fish

@@ -1,7 +1,25 @@
 # Fish Shell Completions
-
 # Place or symlink to $XDG_CONFIG_HOME/fish/completions/bat.fish ($XDG_CONFIG_HOME is usually set to ~/.config)
 
+# Helper function:
+function __bat_autocomplete_languages --description "A helper function used by "(status filename)
+	bat --list-languages | awk -F':' '
+		{
+			lang=$1
+			split($2, exts, ",")
+
+			for (i in exts) {
+				ext=exts[i]
+				if (ext !~ /[A-Z].*/ && ext !~ /^\..*rc$/) {
+					print ext"\t"lang
+				}
+			}
+		}
+	' | sort
+end
+
+# Completions:
+
 complete -c bat -l color -xka "auto never always" -d "Specify when to use colored output (default: auto)" -n "not __fish_seen_subcommand_from cache"
 
 complete -c bat -l config-dir -d "Display location of 'bat' configuration directory" -n "not __fish_seen_subcommand_from cache"
@@ -16,9 +34,7 @@ complete -c bat -s H -l highlight-line -x -d "<N> Highlight the N-th line with a
 
 complete -c bat -l italic-text -xka "always never" -d "Specify when to use ANSI sequences for italic text (default: never)" -n "not __fish_seen_subcommand_from cache"
 
-# TODO: add parameter completion for available languages using option:  -xka "(bat --list-languages | cat)"
-# but replace 'cat' with some sed/awk like command that only outputs lines of valid options for this flag
-complete -c bat -s l -l language -d "Set the language for syntax highlighting" -n "not __fish_seen_subcommand_from cache"
+complete -c bat -s l -l language -d "Set the language for syntax highlighting" -n "not __fish_seen_subcommand_from cache" -xa "(__bat_autocomplete_languages)" 
 
 complete -c bat -s r -l line-range -x -d "<N:M> Only print the specified range of lines for each file" -n "not __fish_seen_subcommand_from cache"
 

src/main.rs

@@ -108,48 +108,54 @@ pub fn list_languages(config: &Config) -> Result<()> {
         .collect::<Vec<_>>();
     languages.sort_by_key(|lang| lang.name.to_uppercase());
 
-    let longest = languages
-        .iter()
-        .map(|syntax| syntax.name.len())
-        .max()
-        .unwrap_or(32); // Fallback width if they have no language definitions.
-
-    let comma_separator = ", ";
-    let separator = " ";
-    // Line-wrapping for the possible file extension overflow.
-    let desired_width = config.term_width - longest - separator.len();
-
     let stdout = io::stdout();
     let mut stdout = stdout.lock();
 
-    let style = if config.colored_output {
-        Green.normal()
+    if config.loop_through {
+        for lang in languages {
+            write!(stdout, "{}:{}\n", lang.name, lang.file_extensions.join(","));
+        }
     } else {
-        Style::default()
-    };
-
-    for lang in languages {
-        write!(stdout, "{:width$}{}", lang.name, separator, width = longest)?;
-
-        // Number of characters on this line so far, wrap before `desired_width`
-        let mut num_chars = 0;
-
-        let mut extension = lang.file_extensions.iter().peekable();
-        while let Some(word) = extension.next() {
-            // If we can't fit this word in, then create a line break and align it in.
-            let new_chars = word.len() + comma_separator.len();
-            if num_chars + new_chars >= desired_width {
-                num_chars = 0;
-                write!(stdout, "\n{:width$}{}", "", separator, width = longest)?;
-            }
+        let longest = languages
+            .iter()
+            .map(|syntax| syntax.name.len())
+            .max()
+            .unwrap_or(32); // Fallback width if they have no language definitions.
+
+        let comma_separator = ", ";
+        let separator = " ";
+        // Line-wrapping for the possible file extension overflow.
+        let desired_width = config.term_width - longest - separator.len();
+
+        let style = if config.colored_output {
+            Green.normal()
+        } else {
+            Style::default()
+        };
 
-            num_chars += new_chars;
-            write!(stdout, "{}", style.paint(&word[..]))?;
-            if extension.peek().is_some() {
-                write!(stdout, "{}", comma_separator)?;
+        for lang in languages {
+            write!(stdout, "{:width$}{}", lang.name, separator, width = longest)?;
+
+            // Number of characters on this line so far, wrap before `desired_width`
+            let mut num_chars = 0;
+
+            let mut extension = lang.file_extensions.iter().peekable();
+            while let Some(word) = extension.next() {
+                // If we can't fit this word in, then create a line break and align it in.
+                let new_chars = word.len() + comma_separator.len();
+                if num_chars + new_chars >= desired_width {
+                    num_chars = 0;
+                    write!(stdout, "\n{:width$}{}", "", separator, width = longest)?;
+                }
+
+                num_chars += new_chars;
+                write!(stdout, "{}", style.paint(&word[..]))?;
+                if extension.peek().is_some() {
+                    write!(stdout, "{}", comma_separator)?;
+                }
             }
+            writeln!(stdout)?;
         }
-        writeln!(stdout)?;
     }
 
     Ok(())