F6 #34: delete the dead two-pane diff-view UI, keep the baseline data layer

F10 (#29) made the rendered preview the single review surface and hid the F6
two-pane vscode.diff view (command + ctrl+alt+d set when:false). This removes
that now-unreachable view code:

- DiffViewController: drop toggle/findDiffTab/epochLabel/isDiffOpen, the
  `cowriting-baseline:` TextDocumentContentProvider + BASELINE_SCHEME + baselineUri
  + the content-provider change emitter, and the toggleDiffView command. The
  baseline DATA layer is fully intact — ensureBaseline/advance/pin/capture,
  getBaseline, baselineFilePath, onDidChangeBaseline, persistence (INV-19), and
  the machine-landing auto-advance (INV-18) that F7/F10 consume.
- package.json: remove the toggleDiffView command, its commandPalette entry, and
  the ctrl+alt+d keybinding.
- E2E: diffView suite keeps the baseline-data-layer tests, drops the two-pane
  view tests; the F10 + no-workspace suites assert toggleDiffView is now absent
  (was: declared-but-hidden).

Deliberate deviation from the issue's literal acceptance: pinDiffBaseline is
KEPT. The canonical Solution Design (coauthoring-interactive-review.md §6.7)
scopes the removal to the two-pane VIEW only ("keep the controller + baseline
store"); pin() lives in the baseline lifecycle (§6.4), never touches vscode.diff,
and is exercised by live F7 baseline-reset tests. Where the P3 capture draft and
the approved spec conflict, the spec wins (documentation-leads-automation).

194 unit + 49 E2E green; typecheck + build clean. No F7/F10 behavior change.

Closes #34

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

package.json

@@ -69,14 +69,9 @@
         "title": "Propose Agent Edit (internal seam)",
         "category": "Cowriting"
       },
-      {
-        "command": "cowriting.toggleDiffView",
-        "title": "Cowriting: Toggle Diff View",
-        "category": "Cowriting"
-      },
       {
         "command": "cowriting.pinDiffBaseline",
-        "title": "Cowriting: Pin Diff Baseline to Now",
+        "title": "Cowriting: Pin Review Baseline to Now",
         "category": "Cowriting"
       },
       {
@@ -103,10 +98,6 @@
           "command": "cowriting.rejectProposal",
           "when": "false"
         },
-        {
-          "command": "cowriting.toggleDiffView",
-          "when": "false"
-        },
         {
           "command": "cowriting.pinDiffBaseline",
           "when": "false"
@@ -145,11 +136,6 @@
       ]
     },
     "keybindings": [
-      {
-        "command": "cowriting.toggleDiffView",
-        "key": "ctrl+alt+d",
-        "when": "false"
-      },
       {
         "command": "cowriting.showTrackChangesPreview",
         "key": "ctrl+alt+r",

src/diffViewController.ts

@@ -1,12 +1,15 @@
 /**
- * DiffViewController — F6 diff-view toggle (spec §6.2/§6.4). Owns the baseline
+ * DiffViewController — F6 baseline data layer (spec §6.4/§6.7). Owns the baseline
  * lifecycle (initialize at first sight / advance at every machine landing / pin
- * on demand), serves the baseline as a readonly `cowriting-baseline:` virtual
- * document, and toggles a native vscode.diff (baseline left, the LIVE document
- * right). A pure view: never mutates the document, sidecar, or attribution
- * state (INV-19).
+ * on demand) and serves it to F7/F10 via `getBaseline` + the additive
+ * `onDidChangeBaseline` event. A pure data layer: never mutates the document,
+ * sidecar, or attribution state (INV-19).
  *
- * F6 works on ANY text document, not just workspace files — it needs no
+ * The F6 two-pane `vscode.diff` *view* (toggle UI + the `cowriting-baseline:`
+ * virtual document) was removed in #34 once F10 made the rendered preview the
+ * single review surface; only the baseline store survives here (spec §6.7).
+ *
+ * The baseline works on ANY text document, not just workspace files — it needs no
  * `.threads/` sidecar, only a stable doc identity + a storage home. So it has
  * its OWN diffable predicate (any `file:` or `untitled:` doc), decoupled from
  * F2's workspace `isTracked`. Persistable docs (`file:`) keep their baseline in
@@ -14,40 +17,24 @@
  * untitled buffers have no durable identity, so their baseline is in-memory
  * only (lost on reload) — the same degrade the storage-unavailable path uses.
  */
-import * as path from "node:path";
 import { createHash } from "node:crypto";
 import * as vscode from "vscode";
 import { BaselineStore, type Baseline, type BaselineReason } from "./baselineStore";
 
-export const BASELINE_SCHEME = "cowriting-baseline";
-
 export class DiffViewController implements vscode.Disposable {
   private readonly disposables: vscode.Disposable[] = [];
-  /** Source of truth for the content provider, keyed by `document.uri.toString()`. */
+  /** Source of truth for the baseline, keyed by `document.uri.toString()`. */
   private readonly baselines = new Map<string, Baseline>();
-  private readonly onDidChangeEmitter = new vscode.EventEmitter<vscode.Uri>();
   /** F7 (additive): fires on every baseline capture (open / advance / pin) so
-   *  the track-changes preview refreshes without polling. Mirrors the internal
-   *  content-provider change signal but carries the real document URI. */
+   *  the track-changes preview refreshes without polling. Carries the real
+   *  document URI. */
   private readonly onDidChangeBaselineEmitter = new vscode.EventEmitter<{ uri: string }>();
   readonly onDidChangeBaseline = this.onDidChangeBaselineEmitter.event;
   private storageWarned = false;
 
   constructor(private readonly store: BaselineStore | null) {
-    const provider: vscode.TextDocumentContentProvider = {
-      onDidChange: this.onDidChangeEmitter.event,
-      provideTextDocumentContent: (uri) => {
-        // The baseline URI carries the real document URI in its query (see baselineUri).
-        return this.baselines.get(uri.query)?.text ?? "";
-      },
-    };
     this.disposables.push(
-      this.onDidChangeEmitter,
       this.onDidChangeBaselineEmitter,
-      vscode.workspace.registerTextDocumentContentProvider(BASELINE_SCHEME, provider),
-      vscode.commands.registerCommand("cowriting.toggleDiffView", () =>
-        this.toggle(vscode.window.activeTextEditor),
-      ),
       vscode.commands.registerCommand("cowriting.pinDiffBaseline", () =>
         this.pinCommand(vscode.window.activeTextEditor),
       ),
@@ -60,7 +47,7 @@ export class DiffViewController implements vscode.Disposable {
 
   // ---- diffability / identity --------------------------------------------------------
 
-  /** Any text document F6 can diff: a saved file OR an unsaved buffer. */
+  /** Any text document F6 tracks a baseline for: a saved file OR an unsaved buffer. */
   private isDiffable(document: vscode.TextDocument): boolean {
     return document.uri.scheme === "file" || document.uri.scheme === "untitled";
   }
@@ -76,11 +63,6 @@ export class DiffViewController implements vscode.Disposable {
   private storageKey(uriKey: string): string {
     return createHash("sha256").update(uriKey).digest("hex");
   }
-  /** The readonly virtual-doc URI; its query carries the real document URI. */
-  private baselineUri(document: vscode.TextDocument): vscode.Uri {
-    const name = path.basename(document.uri.path) || "untitled";
-    return vscode.Uri.from({ scheme: BASELINE_SCHEME, path: "/" + name, query: this.uriKey(document) });
-  }
 
   // ---- baseline lifecycle (§6.4) -----------------------------------------------------
 
@@ -109,13 +91,13 @@ export class DiffViewController implements vscode.Disposable {
     this.capture(document, "machine-landing");
   }
 
-  /** Human pin: baseline := now; the open diff visibly empties (left = right). */
+  /** Human pin: baseline := now; the preview's change-marks empty (left = right). */
   pin(document: vscode.TextDocument): void {
     if (!this.isDiffable(document)) return;
     this.capture(document, "pinned");
   }
 
-  /** Capture buffer text at this epoch, persist (if persistable), refresh any open diff. */
+  /** Capture buffer text at this epoch, persist (if persistable), notify F7/F10. */
   private capture(document: vscode.TextDocument, reason: BaselineReason): void {
     const key = this.uriKey(document);
     const baseline: Baseline = { uri: key, text: document.getText(), capturedAt: new Date().toISOString(), reason };
@@ -127,8 +109,6 @@ export class DiffViewController implements vscode.Disposable {
         this.warnStorageOnce();
       }
     }
-    // An open diff re-requests the left side when its baseline URI changes.
-    this.onDidChangeEmitter.fire(this.baselineUri(document));
     this.onDidChangeBaselineEmitter.fire({ uri: key });
   }
 
@@ -136,78 +116,13 @@ export class DiffViewController implements vscode.Disposable {
     if (this.storageWarned) return;
     this.storageWarned = true;
     void vscode.window.showWarningMessage(
-      "Cowriting: diff-view storage is unavailable — baselines are kept in memory only and won't survive a reload.",
+      "Cowriting: baseline storage is unavailable — baselines are kept in memory only and won't survive a reload.",
     );
   }
 
-  // ---- toggle UX (§6.5 PUC-1) --------------------------------------------------------
-
-  /**
-   * If this doc's baseline diff is open → close it and reveal the normal editor;
-   * else open vscode.diff (baseline left, the live document right). Warns only
-   * when there is no active text editor (or a non-diffable scheme).
-   */
-  private async toggle(editor: vscode.TextEditor | undefined): Promise<void> {
-    if (!editor || !this.isDiffable(editor.document)) {
-      void vscode.window.showWarningMessage(
-        "Cowriting: focus a text editor to toggle its diff view.",
-      );
-      return;
-    }
-    const document = editor.document;
-    const openTab = this.findDiffTab(document.uri);
-    if (openTab) {
-      await vscode.window.tabGroups.close(openTab);
-      await vscode.window.showTextDocument(document, { preview: false });
-      return;
-    }
-    this.ensureBaseline(document);
-    const baseline = this.baselines.get(this.uriKey(document))!;
-    const name = path.basename(document.uri.path) || "untitled";
-    const unsaved = this.isPersistable(document) ? "" : " (unsaved)";
-    const title = `${name} — my changes since ${this.epochLabel(baseline)}${unsaved}`;
-    await vscode.commands.executeCommand(
-      "vscode.diff",
-      this.baselineUri(document),
-      document.uri,
-      title,
-      { preview: false },
-    );
-  }
-
-  /** The open baseline-diff tab for this document, if any. */
-  private findDiffTab(modified: vscode.Uri): vscode.Tab | undefined {
-    for (const group of vscode.window.tabGroups.all) {
-      for (const tab of group.tabs) {
-        const input = tab.input;
-        if (
-          input instanceof vscode.TabInputTextDiff &&
-          input.original.scheme === BASELINE_SCHEME &&
-          input.modified.toString() === modified.toString()
-        ) {
-          return tab;
-        }
-      }
-    }
-    return undefined;
-  }
-
-  /** Human-readable epoch for the diff tab title (§5 / §6.5). */
-  private epochLabel(baseline: Baseline): string {
-    const time = new Date(baseline.capturedAt).toLocaleTimeString();
-    switch (baseline.reason) {
-      case "opened":
-        return `opened ${time}`;
-      case "machine-landing":
-        return `Claude landed ${time}`;
-      case "pinned":
-        return `pinned ${time}`;
-    }
-  }
-
   private pinCommand(editor: vscode.TextEditor | undefined): void {
     if (!editor || !this.isDiffable(editor.document)) {
-      void vscode.window.showWarningMessage("Cowriting: focus a text editor to pin its diff baseline.");
+      void vscode.window.showWarningMessage("Cowriting: focus a text editor to pin its review baseline.");
       return;
     }
     this.pin(editor.document);
@@ -219,10 +134,6 @@ export class DiffViewController implements vscode.Disposable {
     const b = this.baselines.get(uriString);
     return b ? { text: b.text, reason: b.reason, capturedAt: b.capturedAt } : undefined;
   }
-  /** Is this doc's baseline diff currently open in any tab group? */
-  isDiffOpen(uriString: string): boolean {
-    return this.findDiffTab(vscode.Uri.parse(uriString)) !== undefined;
-  }
   /** Absolute on-disk path of this doc's persisted baseline, or undefined (untitled/in-memory). */
   baselineFilePath(uriString: string): string | undefined {
     if (!this.store || vscode.Uri.parse(uriString).scheme !== "file") return undefined;

src/extension.ts

@@ -50,13 +50,14 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
     }),
   );
 
-  // --- F6: diff-view toggle (Features #17 + #19) — workspace-INDEPENDENT ---
-  // F6 works on ANY diffable doc (file or untitled), so it is constructed
-  // regardless of whether a folder is open, and its commands are always live
-  // (never stubbed). Baseline lives in VS Code's per-extension GLOBAL storage
-  // (always present), never the repo (INV-19). The machine-landing advance is
-  // wired in the with-root branch below (landings only occur on workspace files
-  // through the seam). The controller self-wires baseline capture on open.
+  // --- F6: baseline data layer (Features #17 + #19) — workspace-INDEPENDENT ---
+  // The two-pane vscode.diff VIEW was removed in #34 (F10's rendered preview is
+  // the single review surface); only the baseline store survives, consumed by
+  // F7/F10. It tracks a baseline for ANY diffable doc (file or untitled), so it
+  // is constructed regardless of whether a folder is open. Baseline lives in VS
+  // Code's per-extension GLOBAL storage (always present), never the repo
+  // (INV-19). The machine-landing advance is wired below. The controller
+  // self-wires baseline capture on open.
   const baselineStorageDir = context.globalStorageUri?.fsPath;
   const baselineStore = baselineStorageDir ? new BaselineStore(baselineStorageDir) : null;
   const diffViewController = new DiffViewController(baselineStore);

test/e2e/suite-no-workspace/noWorkspace.test.ts

@@ -40,8 +40,11 @@ suite("no-workspace authoring (F8 — real folder-less, #8 lineage)", () => {
       "cowriting.toggleAttribution",
       "cowriting.acceptProposal",
       "cowriting.rejectProposal",
+      // #34: the F6 two-pane diff VIEW was removed (F10 preview is the single
+      // review surface); its toggle command is gone (the baseline store stays).
+      "cowriting.toggleDiffView",
     ]) {
-      assert.ok(!all.includes(retired), `${retired} is retired (F10 preview-only)`);
+      assert.ok(!all.includes(retired), `${retired} is retired`);
     }
   });
 
@@ -73,25 +76,24 @@ suite("no-workspace authoring (F8 — real folder-less, #8 lineage)", () => {
     assert.strictEqual(api.sidecarRouter.sidecarPath(key), undefined, "untitled artifact is in-memory only (no disk)");
   });
 
-  // F6 (#19) is workspace-INDEPENDENT: its commands are real (not stubs) even
-  // with no folder open, and the toggle works on an untitled buffer.
-  test("F6 toggle works with no folder open (untitled buffer)", async () => {
+  // F6 (#19) baseline data layer is workspace-INDEPENDENT: it captures a baseline
+  // for an untitled buffer even with no folder open (the two-pane VIEW was
+  // removed in #34; only the data layer remains). pinDiffBaseline stays real.
+  test("F6 baseline data layer works with no folder open (untitled buffer)", async () => {
     const all = await vscode.commands.getCommands(true);
-    assert.ok(all.includes("cowriting.toggleDiffView"), "toggleDiffView registered");
     assert.ok(all.includes("cowriting.pinDiffBaseline"), "pinDiffBaseline registered");
+    const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
+    const api = (await ext.activate()) as CowritingApi;
     const untitled = await vscode.workspace.openTextDocument({ content: "no-folder scratch\n", language: "markdown" });
     await vscode.window.showTextDocument(untitled);
     await new Promise((r) => setTimeout(r, 300));
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
+    const key = untitled.uri.toString();
+    const baseline = api.diffViewController.getBaseline(key);
+    assert.ok(baseline, "baseline captured for the untitled buffer with no folder");
+    assert.strictEqual(baseline!.reason, "opened");
+    // pin resets the baseline to now — works folder-less.
+    await vscode.commands.executeCommand("cowriting.pinDiffBaseline");
     await new Promise((r) => setTimeout(r, 300));
-    const opened = vscode.window.tabGroups.all.some((g) =>
-      g.tabs.some(
-        (t) =>
-          t.input instanceof vscode.TabInputTextDiff &&
-          t.input.original.scheme === "cowriting-baseline" &&
-          t.input.modified.toString() === untitled.uri.toString(),
-      ),
-    );
-    assert.ok(opened, "a cowriting-baseline diff opened for the untitled buffer with no folder");
+    assert.strictEqual(api.diffViewController.getBaseline(key)!.reason, "pinned", "pin works with no folder");
   });
 });

test/e2e/suite/diffView.test.ts

@@ -23,10 +23,13 @@ async function getApi(): Promise<CowritingApi> {
 }
 const settle = () => new Promise((r) => setTimeout(r, 300));
 
-// Order-dependent (F2–F4 pattern): later tests consume earlier state. Owns
-// docs/diffview.md exclusively. F6 works on ANY file (#19), so the last two
-// tests use an out-of-workspace file and an untitled buffer.
-suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no LLM)", () => {
+// The F6 two-pane vscode.diff VIEW was removed in #34 (F10's rendered preview is
+// the single review surface); only the baseline DATA layer survives, consumed by
+// F7/F10. This suite covers that data layer. Order-dependent (F2–F4 pattern):
+// later tests consume earlier state. Owns docs/diffview.md exclusively. The
+// baseline works on ANY file (#19), so the last two tests use an out-of-workspace
+// file and an untitled buffer.
+suite("F6 baseline data layer (host E2E — any file, programmatic seam ingress, no LLM)", () => {
   const TARGET = "A target sentence Claude will rewrite via the seam.";
   const REPLACEMENT = "A SENTENCE CLAUDE REWROTE via the seam.";
 
@@ -40,21 +43,6 @@ suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no
     assert.strictEqual(baseline!.text, doc.getText(), "baseline = open-time buffer");
   });
 
-  test("toggle opens a diff tab (original scheme cowriting-baseline) over the live doc (PUC-1)", async () => {
-    const api = await getApi();
-    assert.strictEqual(api.diffViewController.isDiffOpen(docUri()), false, "no diff open yet");
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
-    await settle();
-    assert.strictEqual(api.diffViewController.isDiffOpen(docUri()), true, "diff tab open");
-    const active = vscode.window.tabGroups.activeTabGroup.activeTab;
-    assert.ok(active && active.input instanceof vscode.TabInputTextDiff, "active tab is a diff");
-    assert.strictEqual(
-      (active!.input as vscode.TabInputTextDiff).original.scheme,
-      "cowriting-baseline",
-      "left side served by the baseline provider",
-    );
-  });
-
   test("typing leaves the baseline unchanged while the buffer diverges", async () => {
     const doc = await openDoc();
     const api = await getApi();
@@ -105,17 +93,17 @@ suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no
     );
   });
 
-  test("pin resets the baseline to now: baseline == buffer, reason pinned (PUC-3)", async () => {
+  test("pin resets the baseline to now: baseline == buffer, reason pinned", async () => {
     const doc = await openDoc();
     const api = await getApi();
     await vscode.commands.executeCommand("cowriting.pinDiffBaseline");
     await settle();
     const baseline = api.diffViewController.getBaseline(docUri())!;
     assert.strictEqual(baseline.reason, "pinned");
-    assert.strictEqual(baseline.text, doc.getText(), "pinned baseline == current buffer (diff empties)");
+    assert.strictEqual(baseline.text, doc.getText(), "pinned baseline == current buffer (change-marks empty)");
   });
 
-  test("the baseline is persisted in GLOBAL storage, never the repo (PUC-4, INV-19)", async () => {
+  test("the baseline is persisted in GLOBAL storage, never the repo (INV-19)", async () => {
     await openDoc();
     const api = await getApi();
     const p = api.diffViewController.baselineFilePath(docUri());
@@ -131,25 +119,7 @@ suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no
     assert.ok(p!.includes(`${path.sep}baselines${path.sep}`), "baseline lives under <globalStorage>/baselines/");
   });
 
-  test("toggle again closes the diff tab and reveals the normal editor (PUC-1)", async () => {
-    const api = await getApi();
-    if (!api.diffViewController.isDiffOpen(docUri())) {
-      await openDoc();
-      await vscode.commands.executeCommand("cowriting.toggleDiffView");
-      await settle();
-    }
-    assert.strictEqual(api.diffViewController.isDiffOpen(docUri()), true, "diff open before close");
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
-    await settle();
-    assert.strictEqual(api.diffViewController.isDiffOpen(docUri()), false, "diff tab closed");
-    assert.strictEqual(
-      vscode.window.activeTextEditor?.document.uri.toString(),
-      docUri(),
-      "the normal editor for the doc is active after closing the diff",
-    );
-  });
-
-  test("toggle works on a file OUTSIDE the workspace folder, persisted in global storage (#19)", async () => {
+  test("a baseline is captured + persisted for a file OUTSIDE the workspace folder (#19)", async () => {
     const api = await getApi();
     const outsideDir = fs.mkdtempSync(path.join(os.tmpdir(), "cowriting-outside-"));
     const outsidePath = path.join(outsideDir, "outside.md");
@@ -162,19 +132,14 @@ suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no
     const baseline = api.diffViewController.getBaseline(outsideUri.toString());
     assert.ok(baseline, "baseline captured for an out-of-folder file");
     assert.strictEqual(baseline!.reason, "opened");
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
-    await settle();
-    assert.strictEqual(api.diffViewController.isDiffOpen(outsideUri.toString()), true, "diff opens for the outside file");
     const fp = api.diffViewController.baselineFilePath(outsideUri.toString());
     assert.ok(fp && fs.existsSync(fp), "outside-file baseline persisted in global storage");
     assert.ok(!fp!.startsWith(WS + path.sep), "not under the workspace folder");
-    // close it so it doesn't bleed into the untitled test's active-tab checks
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
-    await settle();
     fs.rmSync(outsideDir, { recursive: true, force: true });
+    void doc;
   });
 
-  test("toggle works on an UNTITLED buffer, baseline in-memory only (#19)", async () => {
+  test("an UNTITLED buffer gets an in-memory baseline, never persisted to disk (#19)", async () => {
     const api = await getApi();
     const untitled = await vscode.workspace.openTextDocument({ content: "scratch line\n", language: "markdown" });
     await vscode.window.showTextDocument(untitled);
@@ -184,8 +149,5 @@ suite("F6 diff-view toggle (host E2E — any file, programmatic seam ingress, no
     const baseline = api.diffViewController.getBaseline(key);
     assert.ok(baseline, "untitled buffer got an in-memory baseline");
     assert.strictEqual(api.diffViewController.baselineFilePath(key), undefined, "untitled is NOT persisted to disk");
-    await vscode.commands.executeCommand("cowriting.toggleDiffView");
-    await settle();
-    assert.strictEqual(api.diffViewController.isDiffOpen(key), true, "diff opens for the untitled buffer");
   });
 });

test/e2e/suite/f10Review.test.ts

@@ -215,16 +215,19 @@ suite("F10 interactive review (host E2E — preview is the single review surface
       api.attributionController.getSpans("docs/f10clean.md").some((s) => s.authorKind === "agent"),
       "agent span recorded (attribution data layer intact)",
     );
-    // the retired toggle is gone from the palette (no editor decorations — INV-32).
+    // the retired in-editor surfaces are gone from the palette (no editor decorations — INV-32).
     const all = await vscode.commands.getCommands(true);
     assert.ok(!all.includes("cowriting.toggleAttribution"), "cowriting.toggleAttribution is retired");
-    // the F6 diff toggle's keybinding is hidden (when:false) — it is not a user surface.
+    // #34: the F6 two-pane diff VIEW was removed (F10 preview is the single review
+    // surface) — its toggle command + ctrl+alt+d keybinding are gone entirely.
+    assert.ok(!all.includes("cowriting.toggleDiffView"), "cowriting.toggleDiffView command is gone (#34)");
     const pkg = JSON.parse(fs.readFileSync(path.join(__dirname, "../../../../package.json"), "utf8"));
     const dKb = (pkg.contributes.keybindings as Array<{ command: string; key: string; when?: string }>).find(
-      (k) => k.command === "cowriting.toggleDiffView" && k.key === "ctrl+alt+d",
+      (k) => k.command === "cowriting.toggleDiffView",
     );
-    assert.ok(dKb, "the ctrl+alt+d toggleDiffView keybinding is declared");
-    assert.strictEqual(dKb!.when, "false", "…but hidden (when:false) — F6 is a data layer, not a user surface");
+    assert.ok(!dKb, "the toggleDiffView keybinding is gone from package.json (#34)");
+    // …but the F6 baseline data layer survives: pinDiffBaseline stays a real command.
+    assert.ok(all.includes("cowriting.pinDiffBaseline"), "pinDiffBaseline (baseline data layer) is kept");
     void key;
   });
 });