feat(debugger): Browse the debug console history and open diff settings from the keyboard (#162)

- Debug console: typed expressions are kept per project, and Browse Console
  History (⌥⌘E / Ctrl+Alt+E) lists them, most recent first, to put one back
  into the input.
- Diff viewer: Diff Settings (⇧⌘D / Ctrl+Shift+D) opens the viewer options
  (side-by-side / unified, whitespace, highlighting, collapsing, scroll sync)
  as a popup menu.

src/features/debugger/actions.ts

@@ -4,7 +4,7 @@ import { call, commands, isCancelled, isTauri, nextRequestId, type RunConfig, ty
 import { downloadJdkActions } from "@/platform/jdk";
 import { useProject } from "@/platform/project";
 import { activeEditor } from "@/editor/api";
-import { maybeEditorService, notifications, toolWindowService } from "@/workbench/contributions";
+import { maybeEditorService, notifications, showStatusInfo, toolWindowService } from "@/workbench/contributions";
 import { canPlaceBreakpoint } from "./breakpoints/languages";
 import {
   removeAllBreakpoints,
@@ -35,6 +35,7 @@ import {
   type DebugSession,
 } from "./state";
 import { focusedDebugView } from "./ui/focusedView";
+import { browseFocusedConsoleHistory } from "./ui/expressionHistory";
 import { expressionAt, valueHint } from "./editor/valueTooltip";
 import { showHint } from "@/editor/lsp/hint";
 import { pausedLineTargets, startInlineSmartStep } from "./editor/smartStep";
@@ -610,6 +611,16 @@ export function registerDebugActions(): () => void {
       when: "debugSessionActive",
       run: () => openEvaluateDialog(evaluateSeed()),
     },
+    {
+      id: "debug.browseConsoleHistory",
+      title: "Browse Console History",
+      category: "Debug",
+      keywords: ["history", "previous expressions", "repl"],
+      when: "debugSessionActive",
+      run: () => {
+        if (!browseFocusedConsoleHistory()) showStatusInfo(tx("Focus the debug console input first"));
+      },
+    },
     {
       // ⌥⌘F8: the selection (or expression at the caret) evaluated in a value hint, no dialog.
       id: "debug.quickEvaluate",

src/features/debugger/ui/DebugToolWindow.tsx

@@ -39,6 +39,7 @@ import {
   type DebugSession,
 } from "../state";
 import { VariablesView, type VarRoot } from "./VariablesView";
+import { pushHistory, readHistory, setConsoleHistoryBrowser } from "./expressionHistory";
 import styles from "./DebugToolWindow.module.css";
 import { tx } from "@/platform/i18n";
 
@@ -542,8 +543,9 @@ function ConsoleView({ session }: { session: DebugSession }) {
   const scroller = useRef<HTMLDivElement>(null);
   const stick = useRef(true);
   const [input, setInput] = useState("");
-  const history = useRef<string[]>([]);
+  const history = useRef<string[]>(readHistory("console"));
   const historyPos = useRef(-1);
+  const inputRef = useRef<HTMLInputElement>(null);
 
   useEffect(() => {
     const el = scroller.current;
@@ -553,7 +555,8 @@ function ConsoleView({ session }: { session: DebugSession }) {
   const submit = async () => {
     const e = input.trim();
     if (!e) return;
-    history.current = [e, ...history.current.filter((h) => h !== e)].slice(0, 100);
+    pushHistory("console", e);
+    history.current = readHistory("console");
     historyPos.current = -1;
     setInput("");
     appendConsole(session.id, "input", `> ${e}\n`);
@@ -565,6 +568,24 @@ function ConsoleView({ session }: { session: DebugSession }) {
     }
   };
 
+  /** IDEA's Browse History popup: the expressions typed before, most recent first. */
+  const browseHistory = () => {
+    const el = inputRef.current;
+    const r = el?.getBoundingClientRect();
+    const items: MenuItem[] = history.current.length
+      ? history.current.slice(0, 30).map((h, i) => ({
+          id: String(i),
+          label: h.length > 120 ? `${h.slice(0, 120)}…` : h,
+          run: () => {
+            setInput(h);
+            historyPos.current = i;
+            el?.focus();
+          },
+        }))
+      : [{ id: "none", label: "No history", disabled: true }];
+    showContextMenu({ x: r?.left ?? 120, y: (r?.top ?? 200) - 4 }, items);
+  };
+
   const onKeyDown = (e: KeyboardEvent<HTMLInputElement>) => {
     if (e.key === "Enter") {
       e.preventDefault();
@@ -607,7 +628,10 @@ function ConsoleView({ session }: { session: DebugSession }) {
           ›
         </span>
         <input
+          ref={inputRef}
           className={styles.evalInput}
+          onFocus={() => setConsoleHistoryBrowser(browseHistory)}
+          onBlur={() => setConsoleHistoryBrowser(null)}
           value={input}
           onChange={(e) => setInput(e.target.value)}
           onKeyDown={onKeyDown}

src/features/debugger/ui/expressionHistory.ts

@@ -1,10 +1,10 @@
 /**
  * Per-project history of expressions typed into the debugger (breakpoint
- * conditions, Evaluate), most recent first, as IDEA keeps them.
+ * conditions, Evaluate, the debug console), most recent first, as IDEA keeps them.
  */
 import { useProject } from "@/platform/project";
 
-export type HistoryKind = "condition" | "evaluate";
+export type HistoryKind = "condition" | "evaluate" | "console";
 
 const PREFIX = "openidea.debugger.history.";
 const MAX = 50;
@@ -36,3 +36,16 @@ export function pushHistory(kind: HistoryKind, expression: string) {
     // Storage unavailable: no history.
   }
 }
+
+/** Browse History (⌥⌘E) of the focused debug console input, while one has focus. */
+let browseConsoleHistory: (() => void) | null = null;
+
+export function setConsoleHistoryBrowser(fn: (() => void) | null) {
+  browseConsoleHistory = fn;
+}
+
+export function browseFocusedConsoleHistory(): boolean {
+  if (!browseConsoleHistory) return false;
+  browseConsoleHistory();
+  return true;
+}

src/features/vcs/DiffEditor.tsx

@@ -21,7 +21,7 @@ import { setContext } from "@/platform/context";
 import { call, commands } from "@/platform/ipc";
 import { bindingsFor, normalizeBinding, shortcutLabel, strokeOf } from "@/platform/keymap";
 import { tx } from "@/platform/i18n";
-import { IconButton, Select, Spinner, T } from "@/ui";
+import { IconButton, Select, Spinner, T, showContextMenu } from "@/ui";
 import { editorService, type EditorInput } from "@/workbench/contributions";
 import { languageFor, viewerBase } from "./cm";
 import { applyChunk, arrowControls, chunkAt, hoverRevert } from "./diffControls";
@@ -602,9 +602,70 @@ export function DiffEditor({ input }: { input: EditorInput }) {
     const neighbour = chainNeighbour(data, dir);
     if (neighbour) void openDiff(neighbour, { preview: true });
   };
-  const nav = useRef<DiffNavigator>({ next: () => step(1), prev: () => step(-1), jumpToSource, applyChange, file });
+  const toolbarRef = useRef<HTMLDivElement | null>(null);
+  const showSettings = () => {
+    const r = toolbarRef.current?.getBoundingClientRect();
+    showContextMenu({ x: r ? r.left + 8 : 120, y: r ? r.bottom : 120 }, [
+      { kind: "header", label: "Viewer" },
+      {
+        id: "split",
+        label: "Side-by-side Viewer",
+        checked: opts.mode === "split",
+        run: () => setOpts({ mode: "split" }),
+      },
+      {
+        id: "unified",
+        label: "Unified Viewer",
+        checked: opts.mode === "unified",
+        run: () => setOpts({ mode: "unified" }),
+      },
+      { kind: "separator" },
+      {
+        id: "ignore",
+        label: "Ignore Whitespace",
+        submenu: IGNORE_OPTIONS.map((o) => ({
+          id: o.value,
+          label: o.label,
+          checked: opts.ignore === o.value,
+          run: () => setOpts({ ignore: o.value }),
+        })),
+      },
+      {
+        id: "highlight",
+        label: "Highlighting",
+        submenu: HIGHLIGHT_OPTIONS.map((o) => ({
+          id: o.value,
+          label: o.label,
+          checked: opts.highlight === o.value,
+          run: () => setOpts({ highlight: o.value }),
+        })),
+      },
+      { kind: "separator" },
+      {
+        id: "collapse",
+        label: "Collapse Unchanged Fragments",
+        checked: opts.collapse,
+        run: () => setOpts({ collapse: !opts.collapse }),
+      },
+      {
+        id: "sync",
+        label: "Synchronize Scrolling",
+        checked: opts.syncScroll,
+        disabled: opts.mode !== "split",
+        run: () => setOpts({ syncScroll: !opts.syncScroll }),
+      },
+    ]);
+  };
+  const nav = useRef<DiffNavigator>({
+    next: () => step(1),
+    prev: () => step(-1),
+    jumpToSource,
+    applyChange,
+    file,
+    showSettings,
+  });
   useEffect(() => {
-    nav.current = { next: () => step(1), prev: () => step(-1), jumpToSource, applyChange, file };
+    nav.current = { next: () => step(1), prev: () => step(-1), jumpToSource, applyChange, file, showSettings };
   });
 
   useEffect(
@@ -638,7 +699,7 @@ export function DiffEditor({ input }: { input: EditorInput }) {
         }
       }}
     >
-      <div className={styles.toolbar} role="toolbar" aria-label={tx("Diff")}>
+      <div ref={toolbarRef} className={styles.toolbar} role="toolbar" aria-label={tx("Diff")}>
         <IconButton
           icon="arrow-up"
           title="Previous Difference"

src/features/vcs/compare.tsx

@@ -125,6 +125,15 @@ export function registerCompareActions(): () => void {
       when: "diffEditorFocus",
       run: () => focusedDiffNavigator()?.prev(),
     },
+    {
+      id: "diff.showSettings",
+      title: "Diff Settings",
+      category: "Diff",
+      icon: "settings",
+      keywords: ["ignore whitespace", "highlighting", "side-by-side", "unified"],
+      when: "diffEditorFocus",
+      run: () => focusedDiffNavigator()?.showSettings(),
+    },
     {
       id: "diff.nextFile",
       title: "Compare Next File",

src/features/vcs/diffNavigator.ts

@@ -8,6 +8,8 @@ export interface DiffNavigator {
   applyChange(source: "a" | "b"): boolean;
   /** Open the next / previous file of the diff chain (changes of a commit or change list). */
   file(dir: 1 | -1): void;
+  /** The viewer's settings as a popup menu (⇧⌘D). */
+  showSettings(): void;
 }
 
 let focused: DiffNavigator | null = null;