From c9bca100bd41217e09436d7e1d3fd0aa7b765c7c Mon Sep 17 00:00:00 2001
From: "Alice C. Munduruca" <alice@cremfuelled.net>
Date: Mon, 2 Sep 2024 03:03:39 -0400
Subject: [PATCH] First working sort

---
 helix-term/src/ui/mod.rs | 54 +++++++++++++++++++++++++++++++++++++---
 1 file changed, 51 insertions(+), 3 deletions(-)

diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index 6a3e198c1..e11cc31b1 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -422,6 +422,47 @@ pub mod completers {
         Accept,
     }
 
+    fn best_match(opt1: &str, opt2: &str, input: &str) -> std::cmp::Ordering {
+        let min_len = std::cmp::min(std::cmp::min(opt1.len(), opt2.len()), input.len());
+
+        let mut opt1vals = (0, false);
+        let mut opt2vals = (0, false);
+
+        for i in 0..min_len {
+            if opt1vals.1 && opt2vals.1 {
+                break;
+            }
+
+            if !opt1vals.1 {
+                if opt1[i..=i] == input[i..=i] {
+                    opt1vals.0 += 1;
+                } else {
+                    opt1vals.1 = true;
+                }
+            }
+
+            if !opt2vals.1 {
+                if opt2[i..=i] == input[i..=i] {
+                    opt2vals.0 += 1;
+                } else {
+                    opt2vals.1 = true;
+                }
+            }
+        }
+
+        let ord = opt2vals.0.cmp(&opt1vals.0);
+
+        if ord == std::cmp::Ordering::Equal {
+            if opt1.len() < opt2.len() {
+                return std::cmp::Ordering::Less;
+            } else if opt1.len() > opt2.len() {
+                return std::cmp::Ordering::Greater;
+            }
+        }
+
+        ord
+    }
+
     // TODO: we could return an iter/lazy thing so it can fetch as many as it needs.
     fn filename_impl<F>(
         _editor: &Editor,
@@ -437,6 +478,10 @@ pub mod completers {
         use ignore::WalkBuilder;
         use std::path::Path;
 
+        let input_filename = input
+            .split(std::path::MAIN_SEPARATOR)
+            .last()
+            .unwrap_or_default();
         let is_tilde = input == "~";
         let path = helix_stdx::path::expand_tilde(Path::new(input));
 
@@ -509,12 +554,15 @@ pub mod completers {
         // if empty, return a list of dirs and files in current dir
         if let Some(file_name) = file_name {
             let range = (input.len().saturating_sub(file_name.len()))..;
-            fuzzy_match(&file_name, files, true)
+            let mut files: Vec<_> = fuzzy_match(&file_name, files, true)
                 .into_iter()
                 .map(|(name, _)| (range.clone(), name))
-                .collect()
+                .collect();
 
-            // TODO: complete to longest common match
+            files.sort_unstable_by(|(_, path1), (_, path2)| {
+                best_match(path1, path2, input_filename)
+            });
+            files
         } else {
             let mut files: Vec<_> = files.map(|file| (end.clone(), file)).collect();
             files.sort_unstable_by(|(_, path1), (_, path2)| path1.cmp(path2));