[Perf] add comments for highlight logic

generator/src/code.rs

@@ -10,6 +10,8 @@ fn min_width(width: f32) -> f32 {
     }
 }
 
+// Because the code block is input by users, we need to calculate the width and height
+// to make sure render the width and height of the "editor" shape correctly
 pub fn calc_wh(text: &str, char_wdith: f32, line_height: f32) -> (f32, f32) {
     let trimmed_text = prepare_code(text);
     let lines = trimmed_text.lines();
@@ -41,8 +43,7 @@ fn trim_space(text: &str) -> String {
     let head_spaces = Regex::new(r"^(\s*)").unwrap().find(first_line);
 
     match head_spaces {
-        Some(head_spaces) => {
-            return lines
+        Some(head_spaces) => lines
             .into_iter()
             .map(|line| {
                 Regex::new(format!("^{}", head_spaces.as_str()).as_ref())
@@ -51,12 +52,11 @@ fn trim_space(text: &str) -> String {
                     .to_string()
             })
             .collect::<Vec<String>>()
-                .join("\n");
-        }
+            .join("\n"),
         None => text.to_string(),
     }
 }
 
 pub fn prepare_code(code: &str) -> String {
-    replace_tab_to_space(&trim_space(&code))
+    trim_space(&replace_tab_to_space(&code))
 }

generator/src/highlight.rs

@@ -53,6 +53,9 @@ impl Highlight {
                 ))?,
         };
 
+        // The Syntect clearly distinguish between PHP and PHP Source
+        // Should use PHP as highlight language if the source content contains "<php" tag
+        // Should use PHP Source as highlight language if the source content not contains "<php" tag
         if let Some(identifier) = self.highlighting_language_source_map.get(&syntax.name[..]) {
             if !self.content.contains(identifier) {
                 return Ok(syntax_set
@@ -77,11 +80,14 @@ impl Highlight {
         let mut highlight = HighlightLines::new(syntax, &theme_set.themes[theme]);
         let attrs = Attrs::new().family(Family::Name(self.font_family.as_ref()));
 
+        // Highlight the content line by line using highlight_line function
         Ok(LinesWithEndings::from(&self.content)
-            .map(|line| highlight.highlight_line(line, &syntax_set).unwrap())
-            .fold(vec![], |acc, cur| [acc, cur].concat())
+            .map(|line| {
+                highlight
+                    .highlight_line(line, &syntax_set)
+                    .unwrap()
                     .into_iter()
-            .map(move |(style, str)| {
+                    .map(|(style, str)| {
                         let syntect::highlighting::Color { r, g, b, a: _ } = style.foreground;
                         let attrs = match style.font_style {
                             FontStyle::BOLD => attrs.weight(Weight::BOLD),
@@ -92,6 +98,10 @@ impl Highlight {
 
                         (str, attrs.color(cosmic_text::Color::rgb(r, g, b)))
                     })
+                    .collect::<HighlightResult>()
+            })
+            .fold(vec![], |acc, cur| [acc, cur].concat())
+            .into_iter()
             .collect::<HighlightResult>())
     }
 }