From 92e12dbe8812df1da323117b5ee85a1f18c09335 Mon Sep 17 00:00:00 2001
From: Gokul Soumya <gokulps15@gmail.com>
Date: Thu, 2 Feb 2023 19:23:06 +0530
Subject: [PATCH] Move FilePicker::render from Component impl to normal impl

Merges the code for the Picker and FilePicker into a single Picker that
can show a file preview if a preview callback is provided. This change
was mainly made to facilitate refactoring out a simple skeleton of a
picker that does not do any filtering to be reused in a normal Picker
and a DynamicPicker (see #5714; in particular [mikes-comment] and
[gokuls-comment]).

The crux of the issue is that a picker maintains a list of predefined
options (eg. list of files in the directory) and (re-)filters them every
time the picker prompt changes, while a dynamic picker (eg. interactive
global search, #4687) recalculates the full list of options on every
prompt change. Using a filtering picker to drive a dynamic picker hence
does duplicate work of filtering thousands of matches for no reason. It
could also cause problems like interfering with the regex pattern in the
global search.

I tried to directly extract a PickerBase to be reused in Picker and
FilePicker and DynamicPicker, but the problem is that DynamicPicker is
actually a DynamicFilePicker (i.e. it can preview file contents) which
means we would need PickerBase, Picker, FilePicker, DynamicPicker and
DynamicFilePicker and then another way of sharing the previewing code
between a FilePicker and a DynamicFilePicker. By merging Picker and
FilePicker into Picker, we only need PickerBase, Picker and
DynamicPicker.

[gokuls-comment]: https://github.com/helix-editor/helix/issues/5714#issuecomment-1410949578
[mikes-comment]: https://github.com/helix-editor/helix/issues/5714#issuecomment-1407451963
---
 helix-term/src/ui/picker.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index 5fa75136f1048..e1edefadb7718 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -120,7 +120,7 @@ impl Preview<'_, '_> {
     }
 }
 
-impl<T: Item> FilePicker<T> {
+impl<T: Item + 'static> FilePicker<T> {
     pub fn new(
         options: Vec<T>,
         editor_data: T::Data,
@@ -227,10 +227,8 @@ impl<T: Item> FilePicker<T> {
 
         EventResult::Consumed(None)
     }
-}
 
-impl<T: Item + 'static> Component for FilePicker<T> {
-    fn render(&mut self, area: Rect, surface: &mut Surface, cx: &mut Context) {
+    fn render_picker(&mut self, area: Rect, surface: &mut Surface, cx: &mut Context) {
         // +---------+ +---------+
         // |prompt   | |preview  |
         // +---------+ |         |
@@ -345,6 +343,12 @@ impl<T: Item + 'static> Component for FilePicker<T> {
             );
         }
     }
+}
+
+impl<T: Item + 'static> Component for FilePicker<T> {
+    fn render(&mut self, area: Rect, surface: &mut Surface, cx: &mut Context) {
+        self.render_picker(area, surface, cx)
+    }
 
     fn handle_event(&mut self, event: &Event, ctx: &mut Context) -> EventResult {
         if let Event::IdleTimeout = event {