Remove prefix filtering from autocomplete menu (#4578)

PR #4134 switched the autocomplete menu from alphabetical to fuzzy
sorting. This commit removes the still existing filtering by prefix and
should enable full fuzzy sorting of the autocomplete menu.

closes #3084, #1807

Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>

helix-term/src/commands.rs

@@ -3950,7 +3950,6 @@ pub fn completion(cx: &mut Context) {
     iter.reverse();
     let offset = iter.take_while(|ch| chars::char_is_word(*ch)).count();
     let start_offset = cursor.saturating_sub(offset);
-    let prefix = text.slice(start_offset..cursor).to_string();
 
     cx.callback(
         future,
@@ -3960,7 +3959,7 @@ pub fn completion(cx: &mut Context) {
                 return;
             }
 
-            let mut items = match response {
+            let items = match response {
                 Some(lsp::CompletionResponse::Array(items)) => items,
                 // TODO: do something with is_incomplete
                 Some(lsp::CompletionResponse::List(lsp::CompletionList {
@@ -3970,15 +3969,6 @@ pub fn completion(cx: &mut Context) {
                 None => Vec::new(),
             };
 
-            if !prefix.is_empty() {
-                items.retain(|item| {
-                    item.filter_text
-                        .as_ref()
-                        .unwrap_or(&item.label)
-                        .starts_with(&prefix)
-                });
-            }
-
             if items.is_empty() {
                 // editor.set_error("No completion available");
                 return;