Feat: LSP Type Hints (#5934)

* misc: missing inline, outdated link

* doc: Add new theme keys and config option to book

* fix: don't panic in Tree::try_get(view_id)

Necessary for later, where we could be receiving an LSP response
for a closed window, in which case we don't want to crash while
checking for its existence

* fix: reset idle timer on all mouse events

* refacto: Introduce Overlay::new and InlineAnnotation::new

* refacto: extract make_job_callback from Context::callback

* feat: add LSP display_inlay_hint option to config

* feat: communicate inlay hints support capabilities of helix to LSP server

* feat: Add function to request range of inlay hint from LSP

* feat: Save inlay hints in document, per view

* feat: Update inlay hints on document changes

* feat: Compute inlay hints on idle timeout

* nit: Add todo's about inlay hints for later

* fix: compute text annotations for current view in view.rs, not document.rs

* doc: Improve Document::text_annotations() description

* nit: getters don't use 'get_' in front

* fix: Drop inlay hints annotations on config refresh if necessary

* fix: padding theming for LSP inlay hints

* fix: tracking of outdated inlay hints should not be dependant on document revision (because of undos and such)

* fix: follow LSP spec and don't highlight padding as virtual text

* config: add some LSP inlay hint configs

2 files changed, 10 insertions, 0 deletions

diff --git a/helix-term/src/ui/editor.rs b/helix-term/src/ui/editor.rs
index 4abbe01e..7c22df74 100644
--- a/helix-term/src/ui/editor.rs
+++ b/helix-term/src/ui/editor.rs
@@ -990,6 +990,8 @@ impl EditorView {
     }
 
     pub fn handle_idle_timeout(&mut self, cx: &mut commands::Context) -> EventResult {
+        commands::compute_inlay_hints_for_all_views(cx.editor, cx.jobs);
+
         if let Some(completion) = &mut self.completion {
             return if completion.ensure_item_resolved(cx) {
                 EventResult::Consumed(None)
@@ -1014,6 +1016,10 @@ impl EditorView {
         event: &MouseEvent,
         cxt: &mut commands::Context,
     ) -> EventResult {
+        if event.kind != MouseEventKind::Moved {
+            cxt.editor.reset_idle_timer();
+        }
+
         let config = cxt.editor.config();
         let MouseEvent {
             kind,
diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index ec8b1c7f..bc2f98ee 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -225,6 +225,9 @@ impl<T: Item> FilePicker<T> {
                 let loader = cx.editor.syn_loader.clone();
                 doc.detect_language(loader);
             }
+
+            // QUESTION: do we want to compute inlay hints in pickers too ? Probably not for now
+            // but it could be interesting in the future
         }
 
         EventResult::Consumed(None)
@@ -339,6 +342,7 @@ impl<T: Item + 'static> Component for FilePicker<T> {
                 inner,
                 doc,
                 offset,
+                // TODO: compute text annotations asynchronously here (like inlay hints)
                 &TextAnnotations::default(),
                 highlights,
                 &cx.editor.theme,