keymap_ui: Create language for Zed keybind context (#34558)

Closes #ISSUE

Creates a new language in the languages crate for the DSL used in Zed
keybinding context. Previously, keybind context was highlighted as Rust
in the keymap UI due to the expression syntax of Rust matching that of
the context DSL, however, this had the side effect of highlighting upper
case contexts (e.g. `Editor`) however Rust types would be highlighted
based on the theme. By extracting only the necessary pieces of the Rust
language `highlights.scm`, `brackets.scm`, and `config.toml`, and
continuing to use the Rust grammar, we get a better result across
different themes

Release Notes:

- N/A *or* Added/Fixed/Improved ...

crates/languages/src/lib.rs

@@ -212,6 +212,10 @@ pub fn init(languages: Arc<LanguageRegistry>, node: NodeRuntime, cx: &mut App) {
             name: "gitcommit",
             ..Default::default()
         },
+        LanguageInfo {
+            name: "zed-keybind-context",
+            ..Default::default()
+        },
     ];
 
     for registration in built_in_languages {

crates/languages/src/zed-keybind-context/brackets.scm

@@ -0,0 +1 @@
+("(" @open ")" @close)

crates/languages/src/zed-keybind-context/config.toml

@@ -0,0 +1,6 @@
+name = "Zed Keybind Context"
+grammar = "rust"
+autoclose_before = ")"
+brackets = [
+    { start = "(", end = ")", close = true, newline = false },
+]

crates/languages/src/zed-keybind-context/highlights.scm

@@ -0,0 +1,23 @@
+(identifier) @variable
+
+[
+  "("
+  ")"
+] @punctuation.bracket
+
+[
+  (integer_literal)
+  (float_literal)
+] @number
+
+(boolean_literal) @boolean
+
+[
+  "!="
+  "=="
+  "=>"
+  ">"
+  "&&"
+  "||"
+  "!"
+] @operator

crates/settings_ui/src/keybindings.rs

@@ -505,7 +505,7 @@ impl KeymapEditor {
 
     fn process_bindings(
         json_language: Arc<Language>,
-        rust_language: Arc<Language>,
+        zed_keybind_context_language: Arc<Language>,
         cx: &mut App,
     ) -> (Vec<ProcessedKeybinding>, Vec<StringMatchCandidate>) {
         let key_bindings_ptr = cx.key_bindings();
@@ -536,7 +536,10 @@ impl KeymapEditor {
             let context = key_binding
                 .predicate()
                 .map(|predicate| {
-                    KeybindContextString::Local(predicate.to_string().into(), rust_language.clone())
+                    KeybindContextString::Local(
+                        predicate.to_string().into(),
+                        zed_keybind_context_language.clone(),
+                    )
                 })
                 .unwrap_or(KeybindContextString::Global);
 
@@ -588,11 +591,12 @@ impl KeymapEditor {
         let workspace = self.workspace.clone();
         cx.spawn(async move |this, cx| {
             let json_language = load_json_language(workspace.clone(), cx).await;
-            let rust_language = load_rust_language(workspace.clone(), cx).await;
+            let zed_keybind_context_language =
+                load_keybind_context_language(workspace.clone(), cx).await;
 
             let (action_query, keystroke_query) = this.update(cx, |this, cx| {
                 let (key_bindings, string_match_candidates) =
-                    Self::process_bindings(json_language, rust_language, cx);
+                    Self::process_bindings(json_language, zed_keybind_context_language, cx);
 
                 this.keybinding_conflict_state = ConflictState::new(&key_bindings);
 
@@ -1590,13 +1594,20 @@ impl KeybindingEditorModal {
             }
 
             let editor_entity = input.editor().clone();
+            let workspace = workspace.clone();
             cx.spawn(async move |_input_handle, cx| {
                 let contexts = cx
                     .background_spawn(async { collect_contexts_from_assets() })
                     .await;
 
+                let language = load_keybind_context_language(workspace, cx).await;
                 editor_entity
-                    .update(cx, |editor, _cx| {
+                    .update(cx, |editor, cx| {
+                        if let Some(buffer) = editor.buffer().read(cx).as_singleton() {
+                            buffer.update(cx, |buffer, cx| {
+                                buffer.set_language(Some(language), cx);
+                            });
+                        }
                         editor.set_completion_provider(Some(std::rc::Rc::new(
                             KeyContextCompletionProvider { contexts },
                         )));
@@ -2131,25 +2142,31 @@ async fn load_json_language(workspace: WeakEntity<Workspace>, cx: &mut AsyncApp)
     });
 }
 
-async fn load_rust_language(workspace: WeakEntity<Workspace>, cx: &mut AsyncApp) -> Arc<Language> {
-    let rust_language_task = workspace
+async fn load_keybind_context_language(
+    workspace: WeakEntity<Workspace>,
+    cx: &mut AsyncApp,
+) -> Arc<Language> {
+    let language_task = workspace
         .read_with(cx, |workspace, cx| {
             workspace
                 .project()
                 .read(cx)
                 .languages()
-                .language_for_name("Rust")
+                .language_for_name("Zed Keybind Context")
         })
-        .context("Failed to load Rust language")
+        .context("Failed to load Zed Keybind Context language")
         .log_err();
-    let rust_language = match rust_language_task {
-        Some(task) => task.await.context("Failed to load Rust language").log_err(),
+    let language = match language_task {
+        Some(task) => task
+            .await
+            .context("Failed to load Zed Keybind Context language")
+            .log_err(),
         None => None,
     };
-    return rust_language.unwrap_or_else(|| {
+    return language.unwrap_or_else(|| {
         Arc::new(Language::new(
             LanguageConfig {
-                name: "Rust".into(),
+                name: "Zed Keybind Context".into(),
                 ..Default::default()
             },
             Some(tree_sitter_rust::LANGUAGE.into()),

crates/ui_input/src/ui_input.rs

@@ -135,6 +135,7 @@ impl Render for SingleLineInput {
         let editor_style = EditorStyle {
             background: theme_color.ghost_element_background,
             local_player: cx.theme().players().local(),
+            syntax: cx.theme().syntax().clone(),
             text: text_style,
             ..Default::default()
         };