Use trait for username display, fix suggestion username

src/commands/challenge.rs

@@ -149,11 +149,7 @@ pub async fn submit(ctx: Context<'_>, submission: serenity::Attachment) -> Resul
             break;
         }
     }
-    let username = if author.discriminator == 0 { // new usernames
+    let username = author.username();
-        author.name.clone()
-    } else {
-        format!("{}#{}", author.name, author.discriminator)
-    };
     let username = &username;
     if !existing_submitter {
         let mut submitter_data = Map::new();
@@ -470,7 +466,6 @@ pub async fn suggest(
                 am
             });
             m.embed(|e| {
-                let username = format!("{}#{}", author.name, author.discriminator);
                 e.title("New suggestion");
                 e.description(if let Context::Prefix(ctx) = ctx {
                     format!("{suggestion}\n\n[See original message]({})", ctx.msg.link(),)
@@ -480,7 +475,7 @@ pub async fn suggest(
                 let mut embed_author = serenity::builder::CreateEmbedAuthor::default();
                 embed_author
                     .icon_url(get_avatar(author))
-                    .name(username)
+                    .name(author.username())
                     .url(format!("https://discord.com/users/{}", author.id));
                 e.set_author(embed_author);
                 if let Some(accent_color) = accent_color {

src/utils.rs

@@ -13,6 +13,19 @@ use std::io::Read;
 use std::io::Write;
 use std::process::Command;
 
+pub trait User {
+    fn username(&self) -> String;
+}
+
+impl User for serenity::User {
+    fn username(&self) -> String {
+        if self.discriminator == 0 {
+            return self.name.clone();
+        }
+        format!("{}#{}", self.name, self.discriminator)
+    }
+}
+
 pub fn get_challenge_number() -> i32 {
     let challenge_dir = format!("{}/content/challenges", env::var("HUGO").unwrap());
     let paths = fs::read_dir(challenge_dir).unwrap();
@@ -386,6 +399,7 @@ pub async fn leaderboard(ctx: &Context<'_>) -> Result<(), Error> {
         let discriminator = user.discriminator;
         leaderboard_html.push_str(&format!("<tr><td>{place}</td><td><a href=\"{profile}\" target=\"_blank\" class=\"no-underline\"><img src=\"{avatar}\" onerror=\"this.src='/default.png'\"> <span class=\"underline\">{name}"));
         // New usernames have #0000 discriminator
+        // Can't use User trait user.display_name() because of muted span
         if discriminator != 0 {
             leaderboard_html.push_str(&format!("<span class=\"muted\">#{:0>4}</span>", discriminator));
         }