feat: syntax highlighting for diff view

src/screen/dashboard/pull_request_diff_view.rs

@@ -6,9 +6,10 @@ use crate::{
         diff_view::{DiffViewContent, DiffViewState, diff_view},
         text::text,
     },
-    query::{self, QueryStatus, observe_query, read_query, use_query},
+    query::{self, QueryStatus, read_query, use_query, watch_query},
+    util,
 };
-use gpui::{ParentElement, Styled, div};
+use gpui::{AppContext, ParentElement, Styled, div};
 
 pub(crate) struct PullRequestDiffView {
     selected_file_path: Option<Arc<str>>,
@@ -104,23 +105,68 @@ impl PullRequestDiffView {
             },
             cx,
         );
-
-        _ = observe_query(
-            &content_diff_query,
-            |this, query, cx| {
-                if let QueryStatus::Loaded(diff) = read_query(query, cx) {
-                    println!("diff len {}", diff.len());
-                    this.diff_view_state.reset(diff.len());
-                    this.diff_view_content = Some(Arc::clone(diff).into());
-                }
-                cx.notify();
-            },
-            cx,
-        )
-        .detach();
+        _ = watch_query(&content_diff_query, Self::sync_content_diff_query, cx).detach();
 
         self.content_diff_query = Some(content_diff_query);
     }
+
+    fn sync_content_diff_query(
+        &mut self,
+        query: &query::Entity<api::repo::FetchFileDiff>,
+        cx: &mut gpui::Context<Self>,
+    ) {
+        if let Some(diff) = {
+            match read_query(query, cx) {
+            | QueryStatus::Loaded(diff) => Some(Arc::clone(diff)),
+            | _ => None,
+            }
+        } {
+            self.load_diff_view(diff, cx);
+            cx.notify();
+        }
+    }
+
+    fn load_diff_view(
+        &mut self,
+        content_diff: Arc<util::diff::ContentDiff>,
+        cx: &mut gpui::Context<Self>,
+    ) {
+        let theme = app::current_theme(cx);
+        let old_content = content_diff.old_content.clone();
+        let new_content = content_diff.new_content.clone();
+
+        self.diff_view_state.reset(content_diff.len());
+        self.diff_view_content = Some(content_diff.into());
+
+        let theme_syntax = theme.syntax;
+
+        if let Some(path) = &self.selected_file_path {
+            let path = Arc::clone(&path);
+            let file_type = util::file::file_type_from_path(&path);
+
+            let t1 = cx.background_spawn(async move {
+                util::syntax_highlight::highlight_content(old_content, file_type, &theme_syntax)
+            });
+            let t2 = cx.background_spawn(async move {
+                util::syntax_highlight::highlight_content(new_content, file_type, &theme_syntax)
+            });
+
+            _ = cx
+                .spawn(async move |weak, cx| match tokio::join!(t1, t2) {
+                | (Some(old_side_highlights), Some(new_side_highlights)) => {
+                    _ = weak.update(cx, |this, cx| {
+                        this.diff_view_state
+                            .set_old_side_highlights(old_side_highlights);
+                        this.diff_view_state
+                            .set_new_side_highlights(new_side_highlights);
+                        cx.notify();
+                    });
+                }
+                | _ => {}
+                })
+                .detach();
+        }
+    }
 }
 
 impl gpui::Render for PullRequestDiffView {