Improve header to make filename prominent and show recognised language

src/main.rs

@@ -76,7 +76,7 @@ fn main() {
 
     let arena = Arena::new();
 
-    let (lhs, rhs) = match lang {
+    let (lhs, rhs) = match &lang {
         Some(lang) => (
             parse(&arena, &lhs_src, &lang),
             parse(&arena, &rhs_src, &lang),
@@ -117,7 +117,11 @@ fn main() {
     let lhs_colored = apply_colors(&lhs_src, true, &lhs_positions);
     let rhs_colored = apply_colors(&rhs_src, false, &rhs_positions);
 
-    println!("{}", style::header(lhs_path));
+    let lang_name = match &lang {
+        Some(lang) => lang.name.clone(),
+        None => "plain text".to_string(),
+    };
+    println!("{}", style::header(lhs_path, &lang_name));
     print!(
         "{}",
         apply_groups(

src/parse.rs

@@ -40,6 +40,7 @@ impl ConfigDir {
 }
 
 pub struct Language {
+    pub name: String,
     extensions: Vec<String>,
     atom_patterns: Vec<Regex>,
     string_patterns: Vec<Regex>,
@@ -54,7 +55,7 @@ fn read_syntax_toml(src: &str) -> Vec<Language> {
 
     table
         .iter()
-        .map(|(_, value)| lang_from_value(value))
+        .map(|(name, value)| lang_from_value(name, value))
         .collect()
 }
 
@@ -86,9 +87,10 @@ fn as_regex(s: &str) -> Regex {
     Regex::new(&pattern).unwrap()
 }
 
-fn lang_from_value(v: &Value) -> Language {
+fn lang_from_value(name: &str, v: &Value) -> Language {
     let table = v.as_table().unwrap();
     Language {
+        name: name.into(),
         extensions: as_string_vec(v.get("extensions").unwrap()),
         atom_patterns: as_regex_vec(v.get("atom_patterns").unwrap()),
         string_patterns: as_regex_vec(v.get("string_patterns").unwrap()),

src/style.rs

@@ -114,6 +114,6 @@ pub fn apply_colors(s: &str, is_lhs: bool, positions: &[MatchedPos]) -> String {
     apply(s, &styles)
 }
 
-pub fn header(file_name: &str) -> String {
-    format!("Changes to {}", file_name)
+pub fn header(file_name: &str, language_name: &str) -> String {
+    format!("Changes to {} ({})", file_name.white(), language_name)
 }