feat(editor): Show the enclosing declarations with Context Info

View > Context Info (Ctrl+Shift+Q on macOS, Alt+Q on Windows) shows the
class, method and block header lines around the caret in a hint, which helps
when they are scrolled out of view.

src-tauri/src/menu.rs

@@ -442,6 +442,7 @@ pub fn spec(os: Os) -> Vec<Entry> {
             act("code.quickDocumentation", "Quick Documentation"),
             act("code.expressionTypeInfo", "Expression Type Info"),
             act("code.showErrorDescription", "Error Description"),
+            act("editor.contextInfo", "Context Info"),
             act("code.showIntentions", "Show Context Actions"),
             act("code.generate", "Generate…"),
             act("code.overrideMethods", "Override Methods…"),

src/editor/core/actions.ts

@@ -52,6 +52,7 @@ import {
 } from "./cm/folding";
 import { reverseLines, sortLines } from "./cm/lines";
 import { customRegions } from "./cm/regions";
+import { enclosingHeaders } from "./cm/stickyScroll";
 import { moveElementLeft, moveElementRight } from "./cm/moveElement";
 import { caretAnchor, openPopup } from "@/editor/lsp/popupStore";
 import {
@@ -328,6 +329,18 @@ function completeCurrentStatement(view: EditorView, slot: EditorSlot) {
   });
 }
 
+/**
+ * View › Context Info (⌃⇧Q / Alt+Q): the declaration lines around the caret
+ * (class, method, block headers), most useful when they are scrolled away.
+ */
+function showContextInfo(view: EditorView) {
+  const state = view.state;
+  const line = state.doc.lineAt(state.selection.main.head).number;
+  const headers = enclosingHeaders(state, line);
+  const text = headers.map((n) => state.doc.line(n).text.trimEnd()).join("\n");
+  void executeAction("editor.showHint", { text: text || "No context information here" });
+}
+
 /** Navigate › Custom Folding (⌥⌘.): the file's custom regions; picking one moves the caret to it. */
 function showCustomRegions(view: EditorView) {
   const regions = customRegions(view.state.doc);
@@ -574,6 +587,10 @@ export function registerEditorActions(): () => void {
         category: "Editor Actions",
       },
     ),
+    text("editor.contextInfo", "Context Info", (v) => showContextInfo(v), {
+      category: "View",
+      keywords: ["enclosing method", "enclosing class", "where am I"],
+    }),
     text("navigate.customRegion", "Custom Folding…", (v) => showCustomRegions(v), {
       category: "Navigate",
       keywords: ["region", "editor-fold", "go to region"],

src/platform/keymaps/intellij-macos.ts

@@ -123,6 +123,7 @@ export const intellijMacos: Record<string, string[]> = {
   "editor.codeBlockEnd": ["Meta+Alt+]"],
   "editor.codeBlockStartWithSelection": ["Meta+Alt+Shift+["],
   "editor.codeBlockEndWithSelection": ["Meta+Alt+Shift+]"],
+  "editor.contextInfo": ["Ctrl+Shift+Q"],
   "navigate.customRegion": ["Meta+Alt+."],
   "code.expandToLevel1": ["Meta+* 1"],
   "code.expandToLevel2": ["Meta+* 2"],

src/platform/keymaps/intellij-windows.ts

@@ -124,6 +124,7 @@ export const intellijWindows: Record<string, string[]> = {
   "editor.codeBlockEnd": ["Ctrl+]"],
   "editor.codeBlockStartWithSelection": ["Ctrl+Shift+["],
   "editor.codeBlockEndWithSelection": ["Ctrl+Shift+]"],
+  "editor.contextInfo": ["Alt+Q"],
   "navigate.customRegion": ["Ctrl+Alt+."],
   "code.expandToLevel1": ["Ctrl+* 1"],
   "code.expandToLevel2": ["Ctrl+* 2"],

src/platform/keymaps/vscode-macos.ts

@@ -28,6 +28,7 @@ export const vscodeMacos: Record<string, string[]> = {
   "navigate.callHierarchy": ["Alt+Shift+H"],
   "navigate.showFilePath": [],
   "navigate.customRegion": [],
+  "editor.contextInfo": [],
   // editor.action.wordHighlight.next / prev
   "navigate.nextHighlightedUsage": ["F7"],
   "navigate.prevHighlightedUsage": ["Shift+F7"],

src/platform/locales/en.json

@@ -431,6 +431,7 @@
   "menu.code.expandAllToLevel4": "4",
   "menu.code.expandToLevel5": "5",
   "menu.code.expandAllToLevel5": "5",
+  "menu.editor.contextInfo": "Context Info",
   "run.services.configurationCount": "{count} configurations",
   "search.bookmarks.count": "{count, plural, one {# bookmark} other {# bookmarks}}",
   "settings.zoom.hint": "Change with {zoomIn} or {zoomOut}. Set to 100% with {reset}"

src/platform/locales/text/zh.json

@@ -4605,5 +4605,7 @@
   "Copies the change at the caret from the left side to the right one": "将光标处的变更从左侧复制到右侧",
   "Copies the change at the caret from the right side to the left one": "将光标处的变更从右侧复制到左侧",
   "Compare Next File": "比较下一个文件",
-  "Compare Previous File": "比较上一个文件"
+  "Compare Previous File": "比较上一个文件",
+  "Context Info": "上下文信息",
+  "No context information here": "此处没有上下文信息"
 }

src/platform/locales/zh.json

@@ -431,6 +431,7 @@
   "menu.code.expandAllToLevel4": "4",
   "menu.code.expandToLevel5": "5",
   "menu.code.expandAllToLevel5": "5",
+  "menu.editor.contextInfo": "上下文信息",
   "run.services.configurationCount": "{count} 个配置",
   "search.bookmarks.count": "{count} 个书签",
   "settings.zoom.hint": "使用 {zoomIn} 或 {zoomOut} 更改，使用 {reset} 重置为 100%"