Refactor wrap_text case handling

src/wrap.rs

@@ -4,7 +4,7 @@
 //! `docs/architecture.md` and uses the `unicode-width` crate for accurate
 //! display calculations.
 
-use regex::Regex;
+use regex::{Captures, Regex};
 
 static FENCE_RE: std::sync::LazyLock<Regex> =
     std::sync::LazyLock::new(|| Regex::new(r"^\s*(```|~~~).*").unwrap());
@@ -18,6 +18,42 @@ static FOOTNOTE_RE: std::sync::LazyLock<Regex> =
 static BLOCKQUOTE_RE: std::sync::LazyLock<Regex> =
     std::sync::LazyLock::new(|| Regex::new(r"^(\s*(?:>\s*)+)(.*)$").unwrap());
 
+struct PrefixHandler {
+    re: &'static std::sync::LazyLock<Regex>,
+    is_bq: bool,
+    build_prefix: fn(&Captures) -> String,
+    rest_group: usize,
+}
+
+impl PrefixHandler {
+    fn build_bullet_prefix(cap: &Captures) -> String { cap[1].to_string() }
+
+    fn build_footnote_prefix(cap: &Captures) -> String { format!("{}{}", &cap[1], &cap[2]) }
+
+    fn build_blockquote_prefix(cap: &Captures) -> String { cap[1].to_string() }
+}
+
+static HANDLERS: &[PrefixHandler] = &[
+    PrefixHandler {
+        re: &BULLET_RE,
+        is_bq: false,
+        build_prefix: PrefixHandler::build_bullet_prefix,
+        rest_group: 2,
+    },
+    PrefixHandler {
+        re: &FOOTNOTE_RE,
+        is_bq: false,
+        build_prefix: PrefixHandler::build_footnote_prefix,
+        rest_group: 3,
+    },
+    PrefixHandler {
+        re: &BLOCKQUOTE_RE,
+        is_bq: true,
+        build_prefix: PrefixHandler::build_blockquote_prefix,
+        rest_group: 2,
+    },
+];
+
 /// Markdown token emitted by [`tokenize_markdown`].
 #[derive(Debug, PartialEq)]
 pub enum Token<'a> {
@@ -341,7 +377,7 @@ pub fn wrap_text(lines: &[String], width: usize) -> Vec<String> {
     let mut indent = String::new();
     let mut in_code = false;
 
-    for line in lines {
+    'line_loop: for line in lines {
         if FENCE_RE.is_match(line) {
             flush_paragraph(&mut out, &buf, &indent, width);
             buf.clear();
@@ -380,27 +416,21 @@ pub fn wrap_text(lines: &[String], width: usize) -> Vec<String> {
             continue;
         }
 
-        if let Some(cap) = BULLET_RE.captures(line) {
-            let prefix = cap.get(1).unwrap().as_str();
-            let rest = cap.get(2).unwrap().as_str();
-            handle_prefix_line(&mut out, &mut buf, &mut indent, width, prefix, rest, false);
-            continue;
-        }
-
-        if let Some(cap) = FOOTNOTE_RE.captures(line) {
-            let indent_part = cap.get(1).unwrap().as_str();
-            let label_part = cap.get(2).unwrap().as_str();
-            let prefix = format!("{indent_part}{label_part}");
-            let rest = cap.get(3).unwrap().as_str();
-            handle_prefix_line(&mut out, &mut buf, &mut indent, width, &prefix, rest, false);
-            continue;
-        }
-
-        if let Some(cap) = BLOCKQUOTE_RE.captures(line) {
-            let prefix = cap.get(1).unwrap().as_str();
-            let rest = cap.get(2).unwrap().as_str();
-            handle_prefix_line(&mut out, &mut buf, &mut indent, width, prefix, rest, true);
-            continue;
+        for handler in HANDLERS {
+            if let Some(cap) = handler.re.captures(line) {
+                let prefix = (handler.build_prefix)(&cap);
+                let rest = cap.get(handler.rest_group).unwrap().as_str();
+                handle_prefix_line(
+                    &mut out,
+                    &mut buf,
+                    &mut indent,
+                    width,
+                    &prefix,
+                    rest,
+                    handler.is_bq,
+                );
+                continue 'line_loop;
+            }
         }
 
         if buf.is_empty() {