fix lsp config reload (#9415)

`syn_loader` was replaced rather than interior value being replace,
old value was still being referenced and not updated after `:config-refresh`.
By using `ArcSwap` like for `config`, each `.load()` call will return the most
updated value.

Co-authored-by: kyfan <kyfan@email>

6 files changed, 32 insertions, 16 deletions

diff --git a/helix-term/src/application.rs b/helix-term/src/application.rs
index b844b5f0..30df3981 100644
--- a/helix-term/src/application.rs
+++ b/helix-term/src/application.rs
@@ -66,7 +66,7 @@ pub struct Application {
     #[allow(dead_code)]
     theme_loader: Arc<theme::Loader>,
     #[allow(dead_code)]
-    syn_loader: Arc<syntax::Loader>,
+    syn_loader: Arc<ArcSwap<syntax::Loader>>,
 
     signals: Signals,
     jobs: Jobs,
@@ -122,7 +122,7 @@ impl Application {
             })
             .unwrap_or_else(|| theme_loader.default_theme(true_color));
 
-        let syn_loader = std::sync::Arc::new(lang_loader);
+        let syn_loader = Arc::new(ArcSwap::from_pointee(lang_loader));
 
         #[cfg(not(feature = "integration"))]
         let backend = CrosstermBackend::new(stdout(), &config.editor);
@@ -391,7 +391,8 @@ impl Application {
     /// refresh language config after config change
     fn refresh_language_config(&mut self) -> Result<(), Error> {
         let lang_loader = helix_core::config::user_lang_loader()?;
-        self.syn_loader = std::sync::Arc::new(lang_loader);
+
+        self.syn_loader.store(Arc::new(lang_loader));
         self.editor.syn_loader = self.syn_loader.clone();
         for document in self.editor.documents.values_mut() {
             document.detect_language(self.syn_loader.clone());
diff --git a/helix-term/src/ui/lsp.rs b/helix-term/src/ui/lsp.rs
index 7037b155..879f963e 100644
--- a/helix-term/src/ui/lsp.rs
+++ b/helix-term/src/ui/lsp.rs
@@ -1,5 +1,6 @@
 use std::sync::Arc;
 
+use arc_swap::ArcSwap;
 use helix_core::syntax;
 use helix_view::graphics::{Margin, Rect, Style};
 use tui::buffer::Buffer;
@@ -18,13 +19,17 @@ pub struct SignatureHelp {
     active_param_range: Option<(usize, usize)>,
 
     language: String,
-    config_loader: Arc<syntax::Loader>,
+    config_loader: Arc<ArcSwap<syntax::Loader>>,
 }
 
 impl SignatureHelp {
     pub const ID: &'static str = "signature-help";
 
-    pub fn new(signature: String, language: String, config_loader: Arc<syntax::Loader>) -> Self {
+    pub fn new(
+        signature: String,
+        language: String,
+        config_loader: Arc<ArcSwap<syntax::Loader>>,
+    ) -> Self {
         Self {
             signature,
             signature_doc: None,
diff --git a/helix-term/src/ui/markdown.rs b/helix-term/src/ui/markdown.rs
index 5cf530ad..749d5850 100644
--- a/helix-term/src/ui/markdown.rs
+++ b/helix-term/src/ui/markdown.rs
@@ -1,4 +1,5 @@
 use crate::compositor::{Component, Context};
+use arc_swap::ArcSwap;
 use tui::{
     buffer::Buffer as Surface,
     text::{Span, Spans, Text},
@@ -31,7 +32,7 @@ pub fn highlighted_code_block<'a>(
     text: &str,
     language: &str,
     theme: Option<&Theme>,
-    config_loader: Arc<syntax::Loader>,
+    config_loader: Arc<ArcSwap<syntax::Loader>>,
     additional_highlight_spans: Option<Vec<(usize, std::ops::Range<usize>)>>,
 ) -> Text<'a> {
     let mut spans = Vec::new();
@@ -48,6 +49,7 @@ pub fn highlighted_code_block<'a>(
 
     let ropeslice = RopeSlice::from(text);
     let syntax = config_loader
+        .load()
         .language_configuration_for_injection_string(&InjectionLanguageMarker::Name(
             language.into(),
         ))
@@ -121,7 +123,7 @@ pub fn highlighted_code_block<'a>(
 pub struct Markdown {
     contents: String,
 
-    config_loader: Arc<syntax::Loader>,
+    config_loader: Arc<ArcSwap<syntax::Loader>>,
 }
 
 // TODO: pre-render and self reference via Pin
@@ -140,7 +142,7 @@ impl Markdown {
     ];
     const INDENT: &'static str = "  ";
 
-    pub fn new(contents: String, config_loader: Arc<syntax::Loader>) -> Self {
+    pub fn new(contents: String, config_loader: Arc<ArcSwap<syntax::Loader>>) -> Self {
         Self {
             contents,
             config_loader,
diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index efa2473e..d27e8355 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -336,8 +336,8 @@ pub mod completers {
     pub fn language(editor: &Editor, input: &str) -> Vec<Completion> {
         let text: String = "text".into();
 
-        let language_ids = editor
-            .syn_loader
+        let loader = editor.syn_loader.load();
+        let language_ids = loader
             .language_configs()
             .map(|config| &config.language_id)
             .chain(std::iter::once(&text));
diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index 4be5a11e..c2728888 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -461,14 +461,17 @@ impl<T: Item + 'static> Picker<T> {
 
         // Then attempt to highlight it if it has no language set
         if doc.language_config().is_none() {
-            if let Some(language_config) = doc.detect_language_config(&cx.editor.syn_loader) {
+            if let Some(language_config) = doc.detect_language_config(&cx.editor.syn_loader.load())
+            {
                 doc.language = Some(language_config.clone());
                 let text = doc.text().clone();
                 let loader = cx.editor.syn_loader.clone();
                 let job = tokio::task::spawn_blocking(move || {
-                    let syntax = language_config.highlight_config(&loader.scopes()).and_then(
-                        |highlight_config| Syntax::new(text.slice(..), highlight_config, loader),
-                    );
+                    let syntax = language_config
+                        .highlight_config(&loader.load().scopes())
+                        .and_then(|highlight_config| {
+                            Syntax::new(text.slice(..), highlight_config, loader)
+                        });
                     let callback = move |editor: &mut Editor, compositor: &mut Compositor| {
                         let Some(syntax) = syntax else {
                             log::info!("highlighting picker item failed");
diff --git a/helix-term/src/ui/prompt.rs b/helix-term/src/ui/prompt.rs
index 3764bba6..a6ee7f05 100644
--- a/helix-term/src/ui/prompt.rs
+++ b/helix-term/src/ui/prompt.rs
@@ -1,5 +1,6 @@
 use crate::compositor::{Component, Compositor, Context, Event, EventResult};
 use crate::{alt, ctrl, key, shift, ui};
+use arc_swap::ArcSwap;
 use helix_core::syntax;
 use helix_view::input::KeyEvent;
 use helix_view::keyboard::KeyCode;
@@ -34,7 +35,7 @@ pub struct Prompt {
     callback_fn: CallbackFn,
     pub doc_fn: DocFn,
     next_char_handler: Option<PromptCharHandler>,
-    language: Option<(&'static str, Arc<syntax::Loader>)>,
+    language: Option<(&'static str, Arc<ArcSwap<syntax::Loader>>)>,
 }
 
 #[derive(Clone, Copy, PartialEq, Eq)]
@@ -98,7 +99,11 @@ impl Prompt {
         self
     }
 
-    pub fn with_language(mut self, language: &'static str, loader: Arc<syntax::Loader>) -> Self {
+    pub fn with_language(
+        mut self,
+        language: &'static str,
+        loader: Arc<ArcSwap<syntax::Loader>>,
+    ) -> Self {
         self.language = Some((language, loader));
         self
     }