Add per view search location and total matches to statusline.

[useche]

This patch changes search_impl to calculate the index of the current match and the total matches in the search. It also adds a new option in the status line to show this information.

[Axlefublr]

love this, was clearly missing

[david-crespo]

Wonderful, I love this. No noticeable lag on an M1 Mac in a 21k line file with 56k matches for ". I think a cap on the number of matches would be fine — 99.9% of the time I would not be hitting the cap.

[Oyyko]

Love it!

[rockboynton]

Nice! This fills a very similar need to #12326, but for searches instead of selections

[useche]

In case it helps anyone else, here are the conflict resolutions and compile fixes required to merge this into master locally.

diff --git a/book/src/editor.md b/book/src/editor.md
index 0000000000..71b273bb0f 100644
--- a/book/src/editor.md
+++ b/book/src/editor.md
@@ -138,13 +138,8 @@
 | `file-type` | The type of the opened file |
 | `diagnostics` | The number of warnings and/or errors |
 | `workspace-diagnostics` | The number of warnings and/or errors on workspace |
-<<<<<<< Conflict 1 of 1
-%%%%%%% Changes from base to side #1
- | `selections` | The number of active selections |
-+| `search-position` | Current search match and total matches in the view `[<current>/<total>]` |
-+++++++ Contents of side #2
 | `selections` | The primary selection index out of the number of active selections |
->>>>>>> Conflict 1 of 1 ends
+| `search-position` | Current search match and total matches in the view `[<current>/<total>]` |
 | `primary-selection-length` | The number of characters currently in primary selection |
 | `position` | The cursor position |
 | `position-percentage` | The cursor position as a percentage of the total number of lines |
diff --git a/helix-term/src/ui/statusline.rs b/helix-term/src/ui/statusline.rs
index 0756033ab3..100a9fa3b1 100644
--- a/helix-term/src/ui/statusline.rs
+++ b/helix-term/src/ui/statusline.rs
@@ -556,15 +556,15 @@
     }
 }
 
-fn render_search_position<F>(context: &mut RenderContext, write: F)
+fn render_search_position<'a, F>(context: &mut RenderContext<'a>, write: F)
 where
-    F: Fn(&mut RenderContext, String, Option<Style>) + Copy,
+    F: Fn(&mut RenderContext<'a>, Span<'a>) + Copy,
 {
     if let Some(SearchMatch { idx, count }) = context.doc.get_last_search_match(context.view.id) {
         let count_str = match count {
             SearchMatchLimit::Limitless(count) => format!("{}", count),
             SearchMatchLimit::Limited(max) => format!(">{}", max),
         };
-        write(context, format!(" [{}/{}] ", idx, count_str), None);
+        write(context, format!(" [{}/{}] ", idx, count_str).into());
     }
 }

I just rebased my branch.

[Axlefublr]

discovered an interesting bug. set editor.search.wrap-around to false (disabling it), then go beyond / after the last search match and press N to get back to it. N no longer works.
it seems like the implementation relies on wrapping, as with wrap-around enabled the N works but tells me “Wrapped around document”, while by all accounts it shouldn't have needed to.

Here's a recording:

compressed.mp4

After I go past the last search match, I spam press N to go back to it, but I get a “No search matches” error message instead.