Sort by total number of lines changed to improve rendered link guess

Author: Urgau

src/github.rs

@@ -1100,6 +1100,9 @@ pub struct PullRequestFile {
     pub sha: String,
     pub filename: String,
     pub blob_url: String,
+    pub additions: u64,
+    pub deletions: u64,
+    pub changes: u64,
 }
 
 #[derive(Debug, serde::Deserialize)]

src/handlers/rendered_link.rs

@@ -40,9 +40,9 @@ async fn add_rendered_link(
     {
         let files = e.issue.files(&ctx.github).await?;
 
-        let rendered_link = files
+        let mut relevant_files: Vec<_> = files
             .iter()
-            .find(|f| {
+            .filter(|f| {
                 config
                     .trigger_files
                     .iter()
@@ -52,7 +52,15 @@ async fn add_rendered_link(
                         .iter()
                         .any(|tf| f.filename.starts_with(tf))
             })
-            .and_then(|file| {
+            .collect();
+
+        // Sort the relavant files by the total number of lines changed, as to
+        // improve our guess for the relevant file to show the link to.
+        relevant_files.sort_by_key(|f| f.additions + f.deletions + f.changes);
+
+        let rendered_link = relevant_files
+            .last()
+            .map(|file| {
                 let head = e.issue.head.as_ref()?;
                 let base = e.issue.base.as_ref()?;
 
@@ -88,7 +96,8 @@ async fn add_rendered_link(
                     },
                     file.filename
                 ))
-            });
+            })
+            .flatten();
 
         let new_body: Cow<'_, str> = if !e.issue.body.contains("[Rendered]") {
             if let Some(rendered_link) = rendered_link {