feat(editor): EditorProposalController — optimistic apply + decorations + CodeLens (#64)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/editorProposalController.ts

@@ -0,0 +1,151 @@
+/**
+ * EditorProposalController — F12/#64 editor surface (spec coauthoring-inline-editor-diff
+ * §3.5). Reverses INV-32 for pending proposals: on `onDidChangeProposals` it
+ * (1) optimistically applies any not-yet-applied proposal into the active editor's
+ * buffer (ProposalController.optimisticApply, INV-48), (2) decorates each applied
+ * proposal — insertion tint over the proposed text + a non-editable struck-red hint
+ * for deletions (INV-52, decorationPlan/INV-49), and (3) provides a CodeLens
+ * `Accept ▾ / Reject ▾` above each block whose ▾ opens a QuickPick (this / all).
+ * Owns no proposal STATE — it is a view over ProposalController (which stays the
+ * pure F4 owner). A document with no pending proposals shows nothing (INV-32's
+ * spirit when nothing is pending).
+ */
+import * as vscode from "vscode";
+import type { ProposalController } from "./proposalController";
+import { decorationPlan } from "./trackChangesModel";
+import { isAuthorable } from "./workspacePath";
+
+export class EditorProposalController implements vscode.Disposable, vscode.CodeLensProvider {
+  private readonly disposables: vscode.Disposable[] = [];
+  private readonly insertionDeco = vscode.window.createTextEditorDecorationType({
+    backgroundColor: new vscode.ThemeColor("diffEditor.insertedTextBackground"),
+  });
+  private readonly deletionDeco = vscode.window.createTextEditorDecorationType({
+    // a non-editable struck-red hint injected AFTER the insertion (INV-52)
+    after: { color: new vscode.ThemeColor("gitDecoration.deletedResourceForeground") },
+    textDecoration: "none",
+  });
+  private readonly lensEmitter = new vscode.EventEmitter<void>();
+  readonly onDidChangeCodeLenses = this.lensEmitter.event;
+  /** Pending debounce timers — one per URI — coalesce rapid-fire propose events
+   * (e.g. runEditAndPropose's N sequential propose() calls) into a single
+   * optimistic-apply pass that runs after ALL proposals are created. Without this,
+   * each propose() fires onDidChangeProposals synchronously and the controller's
+   * optimisticApply runs concurrently with the still-in-progress propose loop,
+   * causing "file changed in the meantime" workspace-edit conflicts. */
+  private readonly pendingApply = new Map<string, ReturnType<typeof setTimeout>>();
+
+  constructor(private readonly proposals: ProposalController) {
+    this.disposables.push(
+      this.insertionDeco, this.deletionDeco, this.lensEmitter,
+      vscode.languages.registerCodeLensProvider({ language: "markdown" }, this),
+      this.proposals.onDidChangeProposals(({ uri }) => this.scheduleApply(uri)),
+      vscode.window.onDidChangeActiveTextEditor((ed) => ed && this.renderEditor(ed)),
+      // the four QuickPick-backed menu commands
+      vscode.commands.registerCommand("cowriting.proposalAcceptMenu", (id?: string) => this.menu("accept", id)),
+      vscode.commands.registerCommand("cowriting.proposalRejectMenu", (id?: string) => this.menu("reject", id)),
+    );
+  }
+
+  /** Debounce-schedule an optimistic-apply pass for the given URI. Multiple rapid
+   * onDidChangeProposals events (from a single runEditAndPropose batch) collapse
+   * into one pass that runs after the batch completes. */
+  private scheduleApply(uri: string): void {
+    const prev = this.pendingApply.get(uri);
+    if (prev !== undefined) clearTimeout(prev);
+    this.pendingApply.set(
+      uri,
+      setTimeout(() => {
+        this.pendingApply.delete(uri);
+        void this.onProposalsChanged(uri);
+      }, 0),
+    );
+  }
+
+  /** Apply any not-yet-applied proposals on the doc, then re-decorate + refresh lenses. */
+  private async onProposalsChanged(uri: string): Promise<void> {
+    const doc = vscode.workspace.textDocuments.find((d) => d.uri.toString() === uri);
+    if (!doc || doc.languageId !== "markdown" || !isAuthorable(doc.uri.scheme)) return;
+    const key = this.proposals.keyFor(doc);
+    for (const v of this.proposals.listProposals(doc)) {
+      if (v.anchorStart !== null && !this.proposals.isApplied(key, v.id)) {
+        await this.proposals.optimisticApply(doc, v.id); // fires onDidChangeProposals again; guarded by isApplied
+      }
+    }
+    const ed = vscode.window.visibleTextEditors.find((e) => e.document.uri.toString() === uri);
+    if (ed) this.renderEditor(ed);
+    this.lensEmitter.fire();
+  }
+
+  /** Decorate the editor for every applied proposal on its document (INV-52). */
+  private renderEditor(editor: vscode.TextEditor): void {
+    const doc = editor.document;
+    if (doc.languageId !== "markdown") {
+      editor.setDecorations(this.insertionDeco, []);
+      editor.setDecorations(this.deletionDeco, []);
+      return;
+    }
+    const key = this.proposals.keyFor(doc);
+    const insertions: vscode.Range[] = [];
+    const deletions: vscode.DecorationOptions[] = [];
+    for (const v of this.proposals.listProposals(doc)) {
+      if (v.anchorStart === null || v.original === undefined || !this.proposals.isApplied(key, v.id)) continue;
+      const plan = decorationPlan(v.anchorStart, v.original, v.replacement);
+      for (const ins of plan.insertions) {
+        insertions.push(new vscode.Range(doc.positionAt(ins.start), doc.positionAt(ins.end)));
+      }
+      for (const del of plan.deletions) {
+        deletions.push({
+          range: new vscode.Range(doc.positionAt(del.at), doc.positionAt(del.at)),
+          renderOptions: { after: { contentText: ` ${del.text} `, textDecoration: "line-through" } },
+        });
+      }
+    }
+    editor.setDecorations(this.insertionDeco, insertions);
+    editor.setDecorations(this.deletionDeco, deletions);
+  }
+
+  /** CodeLensProvider: a `Accept ▾` / `Reject ▾` pair above each applied block. */
+  provideCodeLenses(document: vscode.TextDocument): vscode.CodeLens[] {
+    if (document.languageId !== "markdown") return [];
+    const key = this.proposals.keyFor(document);
+    const lenses: vscode.CodeLens[] = [];
+    for (const v of this.proposals.listProposals(document)) {
+      if (v.anchorStart === null || !this.proposals.isApplied(key, v.id)) continue;
+      const pos = document.positionAt(v.anchorStart);
+      const line = new vscode.Range(pos.line, 0, pos.line, 0);
+      lenses.push(
+        new vscode.CodeLens(line, { title: "Accept ▾", command: "cowriting.proposalAcceptMenu", arguments: [v.id] }),
+        new vscode.CodeLens(line, { title: "Reject ▾", command: "cowriting.proposalRejectMenu", arguments: [v.id] }),
+      );
+    }
+    return lenses;
+  }
+
+  /** The dropdown: this-proposal vs all-proposals, then dispatch. */
+  private async menu(kind: "accept" | "reject", id?: string): Promise<void> {
+    const doc = vscode.window.activeTextEditor?.document;
+    if (!doc || !id) return;
+    const key = this.proposals.keyFor(doc);
+    const verb = kind === "accept" ? "Accept" : "Reject";
+    const pick = await vscode.window.showQuickPick(
+      [`${verb} this proposal`, `${verb} ALL proposals`],
+      { placeHolder: `${verb} Claude's proposal` },
+    );
+    if (!pick) return;
+    const all = pick.includes("ALL");
+    if (kind === "accept") {
+      if (all) await this.proposals.acceptAllProposals(doc);
+      else await this.proposals.finalizeInPlace(key, id);
+    } else {
+      if (all) await this.proposals.rejectAll(doc);
+      else await this.proposals.revertInPlace(key, id);
+    }
+  }
+
+  dispose(): void {
+    for (const t of this.pendingApply.values()) clearTimeout(t);
+    this.pendingApply.clear();
+    for (const d of this.disposables) d.dispose();
+  }
+}

src/extension.ts

@@ -13,6 +13,7 @@ import { DiffViewController } from "./diffViewController";
 import { TrackChangesPreviewController } from "./trackChangesPreview";
 import { LiveProgressUi } from "./liveProgressUi";
 import { InlineAskController } from "./inlineAsk";
+import { EditorProposalController } from "./editorProposalController";
 import { isAuthorable, routeEdit, selectionRejection } from "./workspacePath";
 
 const CHANNEL_NAME = "Cowriting (Cline SDK)";
@@ -27,6 +28,7 @@ export interface CowritingApi {
   sidecarRouter: SidecarRouter;
   liveProgressUi: LiveProgressUi;
   inlineAsk: InlineAskController;
+  editorProposalController: EditorProposalController;
 }
 
 export function activate(context: vscode.ExtensionContext): CowritingApi | undefined {
@@ -123,6 +125,11 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
   );
   context.subscriptions.push(trackChangesPreviewController);
 
+  // --- F12 (#64): the editor surface — optimistic-apply proposals into the buffer,
+  // decorate the diff, and provide Accept ▾/Reject ▾ CodeLens (INV-48/49/52/53). ---
+  const editorProposalController = new EditorProposalController(proposalController);
+  context.subscriptions.push(editorProposalController);
+
   // #46 (INV-42): accept every pending proposal on the active doc in one gesture
   // (also reachable from the preview toolbar's "Accept all" button). Reuses the
   // batched F4 seam + reports applied-vs-skipped.
@@ -345,6 +352,7 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
     sidecarRouter,
     liveProgressUi,
     inlineAsk,
+    editorProposalController,
   };
 }
 

src/proposalController.ts

@@ -91,7 +91,7 @@ export class ProposalController implements vscode.Disposable {
         id: p.id,
         anchorStart: resolved === "orphaned" ? null : resolved.start,
         anchorEnd: resolved === "orphaned" ? null : resolved.end,
-        replaced: fp?.text ?? "",
+        replaced: p.original ?? fp?.text ?? "",
         replacement: p.replacement,
         original: p.original,
       };
@@ -143,7 +143,29 @@ export class ProposalController implements vscode.Disposable {
 
   /** Accept by id — F12: finalize the already-applied text in place (INV-51). */
   async acceptById(docPath: string, proposalId: string, opts?: { silent?: boolean }): Promise<boolean> {
-    if (this.isApplied(docPath, proposalId)) return this.finalizeInPlace(docPath, proposalId);
+    if (this.isApplied(docPath, proposalId)) {
+      // INV-11 (applied path): if an external write mangled the optimistically-applied
+      // text so the fingerprint no longer resolves, refuse finalize — same guard as the
+      // legacy accept path.  Direct finalizeInPlace calls (CodeLens Accept gesture where
+      // the user may have edited inside the applied span) bypass this check intentionally.
+      const hit = this.byId(docPath, proposalId);
+      if (hit) {
+        const document = this.openDoc(hit.state);
+        if (document) {
+          const fp = hit.state.artifact.anchors[hit.proposal.anchorId]?.fingerprint;
+          const resolved = fp ? resolve(document.getText(), fp) : "orphaned";
+          if (resolved === "orphaned") {
+            if (!opts?.silent) {
+              void vscode.window.showWarningMessage(
+                "Cowriting: this proposal's target text changed or is missing — undo to restore it, or reject to discard (it is never applied by guess).",
+              );
+            }
+            return false;
+          }
+        }
+      }
+      return this.finalizeInPlace(docPath, proposalId);
+    }
     // Fallback: a proposal that was never optimistically applied (e.g. orphaned at
     // apply time) keeps the legacy seam-apply accept.
     const hit = this.byId(docPath, proposalId);

test/e2e/suite/f10Review.test.ts

@@ -109,8 +109,9 @@ suite("F10 interactive review (host E2E — preview is the single review surface
     const pIdx = html.indexOf(`data-proposal-id="${id}"`);
     const t2Idx = html.indexOf("second claude target");
     assert.ok(t2Idx >= 0 && pIdx < t2Idx, "the proposal renders in place, before the following block (#31)");
-    // INV-10: proposing never touches the document.
+    // F12 (INV-48): EditorProposalController auto-applies the proposal into the buffer;
-    assert.ok(doc.getText().includes(T1), "document unchanged by propose");
+    // the replacement text is now in the document, proposal is still pending.
+    assert.ok(doc.getText().includes("A FIRST claude REPLACEMENT sentence."), "F12 optimistic-apply: replacement in buffer");
   });
 
   test("accept → the proposal lands, clears from the preview, and the baseline advances (PUC-4)", async () => {
@@ -131,17 +132,18 @@ suite("F10 interactive review (host E2E — preview is the single review surface
     assert.ok(!marked, "the just-landed Claude text renders unmarked (baseline advanced)");
   });
 
-  test("reject → the proposal vanishes and the document is untouched (PUC-5)", async () => {
+  test("reject → the proposal vanishes and the document is reverted (PUC-5)", async () => {
     const { doc, key } = await reopen(DOC_REL);
     const api = await getApi();
     const before = doc.getText();
     const id2 = await propose(doc, key, T2, "A SECOND would-be replacement.", "turn-f10-2");
     await settle();
     assert.ok(api.proposalController.listProposals(doc).some((v) => v.id === id2), "second proposal pending");
-    assert.strictEqual(api.proposalController.rejectById(DOC_REL, id2), true, "reject");
+    // F12: use rejectByIdInPlace to revert the optimistically-applied buffer edit.
+    assert.ok(await api.proposalController.rejectByIdInPlace(DOC_REL, id2), "rejectByIdInPlace reverts + removes");
     await settle();
     assert.ok(!api.proposalController.listProposals(doc).some((v) => v.id === id2), "rejected proposal gone");
-    assert.strictEqual(doc.getText(), before, "document untouched by reject");
+    assert.strictEqual(doc.getText(), before, "document reverted to pre-propose state");
     const html = api.trackChangesPreviewController.renderHtmlFor(key);
     assert.ok(!html.includes(`data-proposal-id="${id2}"`), "no rejected block in the preview");
   });

test/e2e/suite/f11Toolbar.test.ts

@@ -99,8 +99,9 @@ suite("F11 preview toolbar (host E2E — message → seam wiring, no LLM)", () =
       "The quick RED fox jumps over the lazy CAT.",
       "the block proposal carries the whole rewritten paragraph",
     );
-    // INV-10: proposing never mutates the document.
+    // F12 (INV-48): EditorProposalController optimistically applies the proposed text,
-    assert.ok(doc.getText().includes("brown fox") && doc.getText().includes("lazy dog"), "document unchanged by propose");
+    // so after settle the buffer has the replacement. The proposal is still pending.
+    assert.ok(doc.getText().includes("RED fox") && doc.getText().includes("lazy CAT"), "F12 optimistic-apply: proposed text in buffer");
     void key;
   });
 
@@ -129,7 +130,9 @@ suite("F11 preview toolbar (host E2E — message → seam wiring, no LLM)", () =
     assert.ok(view, "the proposal is live");
     assert.strictEqual(view!.replacement, "The REWRITTEN paragraph from Claude.", "carries the turn replacement");
     assert.strictEqual(view!.replaced, target, "replaces exactly the selected range");
-    assert.ok(doc.getText().includes(target), "document unchanged by propose (INV-10)");
+    // F12 (INV-48): the EditorProposalController optimistically applies, so the buffer
+    // now has the replacement. `view.replaced` still records the original target text.
+    assert.ok(doc.getText().includes("The REWRITTEN paragraph from Claude."), "F12 optimistic-apply: proposed text in buffer");
     void key;
   });
 

test/e2e/suite/f12InlineDiff.test.ts

@@ -116,3 +116,39 @@ suite("F12 inline diff — finalize / revert in place (#64, INV-51)", () => {
     assert.strictEqual(p.listProposals(doc).length, 0, "all cleared");
   });
 });
+
+suite("F12 inline diff — editor surface (#64, INV-48/52)", () => {
+  test("proposing optimistically applies into the editor and the buffer is the accepted result", async () => {
+    const { doc } = await freshDoc("docs/f12-editor.md", "# E\n\nThe brown fox runs.\n");
+    const api = await getApi();
+    const ctl = api.trackChangesPreviewController;
+    ctl.setEditTurnForTest(async () => ({ replacement: "# E\n\nThe red fox runs.\n", model: "m", sessionId: "s" }));
+    await ctl.runEditAndPropose(doc, { kind: "document" }, "recolor the fox");
+    await settle(); await settle();
+    assert.ok(doc.getText().includes("The red fox runs."), "optimistically applied into the buffer");
+    const v = api.proposalController.listProposals(doc)[0];
+    assert.strictEqual(v.original, "The brown fox runs.", "original captured for the deletion hint/revert");
+  });
+
+  test("editing the inserted text then finalizing keeps the human edit", async () => {
+    const { doc } = await freshDoc("docs/f12-edit-keep.md", "# E\n\nalpha word here.\n");
+    const api = await getApi();
+    const ctl = api.trackChangesPreviewController;
+    ctl.setEditTurnForTest(async () => ({ replacement: "# E\n\nALPHA word here.\n", model: "m", sessionId: "s" }));
+    const ids = await ctl.runEditAndPropose(doc, { kind: "document" }, "up");
+    await settle(); await settle();
+    // human tweaks the inserted text
+    const at = doc.getText().indexOf("ALPHA");
+    const we = new vscode.WorkspaceEdit();
+    we.replace(doc.uri, new vscode.Range(doc.positionAt(at), doc.positionAt(at + 5)), "ALPHA!");
+    await vscode.workspace.applyEdit(we);
+    await settle();
+    // keyFor(doc) gives the repo-relative path that finalizeInPlace uses as its key;
+    // the `key` from freshDoc is the URI string, which would not match for in-workspace docs.
+    const docKey = api.proposalController.keyFor(doc);
+    await api.proposalController.finalizeInPlace(docKey, ids[0]);
+    await settle();
+    assert.ok(doc.getText().includes("ALPHA! word here."), "human edit preserved on accept");
+    assert.strictEqual(api.proposalController.listProposals(doc).length, 0, "cleared");
+  });
+});

test/e2e/suite/f12Reach.test.ts

@@ -98,8 +98,10 @@ suite("F12 SLICE-1 — Ask-Claude reach (#42, INV-38)", () => {
       0,
       "active doc A was NOT edited — editDocument honored the tab URI",
     );
-    // INV-10: proposing never mutates the document.
+    // F12 (INV-48): EditorProposalController optimistically applies proposals into the
-    assert.ok(b.doc.getText().includes("tab target paragraph"), "tab doc unchanged by propose");
+    // buffer, so the proposed text is now in the tab doc B. Confirm one of the proposal
+    // texts is present (the tab doc was edited, not A).
+    assert.ok(b.doc.getText().includes("REWRITTEN"), "F12 optimistic-apply: proposed text in tab doc B");
   });
 
   // No URI arg (palette / keybinding) → fall back to the active editor.

test/e2e/suite/liveProgress.test.ts

@@ -50,7 +50,10 @@ suite("#60 live turn progress (additive + cancel)", () => {
     assert.strictEqual(ids.length, 1, "one changed block → one proposal, regardless of progress events");
     const view = api.proposalController.listProposals(doc).find((v) => v.id === ids[0]);
     assert.ok(view, "the proposal is live");
-    assert.ok(doc.getText().includes("Old paragraph."), "document unchanged by propose (INV-10)");
+    // F12 (INV-48): the EditorProposalController optimistically applies the proposed
+    // text into the buffer, so after settle the active-editor buffer shows the
+    // replacement. The proposal is still pending (not finalized) until Accept.
+    assert.ok(doc.getText().includes("New paragraph."), "F12 optimistic-apply: proposed text in buffer");
   });
 
   test("an aborted turn proposes nothing (INV-47)", async () => {

test/e2e/suite/proposals.test.ts

@@ -63,13 +63,14 @@ suite("F4 propose/accept (host E2E — programmatic ingress, no LLM)", () => {
   const TARGET = "The propose target sentence lives here.";
   const REPLACEMENT = "PROPOSED-BY-CLAUDE replacement sentence.";
 
-  test("propose records + renders a pending proposal and does NOT touch the document (INV-10)", async () => {
+  test("propose records a pending proposal; F12 optimistically applies it (INV-48, reverses INV-10)", async () => {
     const doc = await openDoc();
     const api = await getApi();
-    const before = doc.getText();
     await proposeViaCommand(doc, TARGET, REPLACEMENT, "turn-p1");
     await settle();
-    assert.strictEqual(doc.getText(), before, "document text unchanged (INV-10)");
+    // F12 (INV-48): EditorProposalController auto-applies the proposed text into the
+    // buffer, so after settle the buffer has the replacement text (INV-10 is reversed).
+    assert.ok(doc.getText().includes(REPLACEMENT), "F12 optimistic-apply: replacement in buffer after propose");
     const rendered = api.proposalController.getRendered(DOC_REL);
     assert.strictEqual(rendered.length, 1);
     assert.strictEqual(rendered[0].pending, true);
@@ -77,7 +78,8 @@ suite("F4 propose/accept (host E2E — programmatic ingress, no LLM)", () => {
     assert.strictEqual(rendered[0].canReply, false, "proposals are decide-only — no dead reply input (INV-12)");
     const art = readSidecar();
     assert.strictEqual(art.proposals.length, 1, "proposal persisted at propose time");
-    assert.strictEqual(art.anchors[art.proposals[0].anchorId].fingerprint.text, TARGET);
+    // After optimistic apply, the fingerprint re-anchors to the replacement text.
+    assert.strictEqual(art.anchors[art.proposals[0].anchorId].fingerprint.text, REPLACEMENT);
   });
 
   test("accept applies via the seam: text replaced, Claude-attributed, proposal removed (INV-9/11/13)", async () => {
@@ -97,15 +99,18 @@ suite("F4 propose/accept (host E2E — programmatic ingress, no LLM)", () => {
     assert.strictEqual(readSidecar().proposals.length, 0, "removed from the sidecar");
   });
 
-  test("reject leaves the document untouched and removes the proposal (PUC-3)", async () => {
+  test("reject reverts the optimistically-applied text and removes the proposal (PUC-3, F12-INV-48)", async () => {
     const doc = await openDoc();
     const api = await getApi();
     const before = doc.getText();
     const id = await proposeViaCommand(doc, "A second target for coexistence checks.", "WOULD-BE replacement.", "turn-p2");
     await settle();
-    assert.strictEqual(api.proposalController.rejectById(DOC_REL, id), true);
+    // F12: optimistic apply has put "WOULD-BE replacement." in the buffer.
+    assert.ok(doc.getText().includes("WOULD-BE replacement."), "F12: optimistically applied");
+    // rejectByIdInPlace reverts the buffer to the original (PUC-3, INV-51).
+    assert.ok(await api.proposalController.rejectByIdInPlace(DOC_REL, id), "rejectByIdInPlace removes + reverts");
     await settle();
-    assert.strictEqual(doc.getText(), before, "document untouched");
+    assert.strictEqual(doc.getText(), before, "document restored to pre-propose state");
     assert.strictEqual(api.proposalController.getRendered(DOC_REL).length, 0);
     assert.strictEqual(readSidecar().proposals.length, 0);
   });
@@ -114,25 +119,35 @@ suite("F4 propose/accept (host E2E — programmatic ingress, no LLM)", () => {
     let doc = await openDoc();
     const api = await getApi();
     const anchor = "A stable closing paragraph.";
-    await proposeViaCommand(doc, anchor, "A PROPOSED closing paragraph.", "turn-p3");
+    const appliedText = "A PROPOSED closing paragraph.";
+    await proposeViaCommand(doc, anchor, appliedText, "turn-p3");
     await settle();
+    // F12: optimistic apply has put the proposed text in the buffer (anchor → appliedText).
+    assert.ok(doc.getText().includes(appliedText), "F12: optimistically applied before reload");
     const uri = vscode.Uri.file(path.join(WS, DOC_REL));
+    // doc.getText() now has appliedText; the reload prepends a line.
     doc = await externalWriteAndReload(uri, "PREPENDED LINE\n\n" + doc.getText());
     await settle();
     api.proposalController.renderAll(doc);
     const rendered = api.proposalController.getRendered(DOC_REL);
     assert.strictEqual(rendered.length, 1, "proposal survived reload");
     assert.strictEqual(rendered[0].pending, true, "still decidable");
-    const moved = doc.getText().indexOf(anchor);
+    // After F12 re-anchor, the fingerprint tracks the appliedText, not the original anchor.
-    assert.strictEqual(rendered[0].range.start, moved, "re-anchored after the move");
+    const moved = doc.getText().indexOf(appliedText);
+    assert.ok(moved >= 0, "applied text present in the reloaded document");
+    assert.strictEqual(rendered[0].range.start, moved, "re-anchored to appliedText after the move");
   });
 
   test("editing the target text makes the proposal stale: flagged, accept refused, doc untouched (INV-11)", async () => {
     let doc = await openDoc();
     const api = await getApi();
     const id = api.proposalController.getRendered(DOC_REL)[0].id;
-    const mangled = doc.getText().replace("A stable closing paragraph.", "A reworded closing paragraph.");
+    // After F12 optimistic apply the fingerprint tracks the APPLIED text ("A PROPOSED
-    doc = await externalWriteAndReload(vscode.Uri.file(path.join(WS, DOC_REL)), mangled);
+    // closing paragraph."), not the original.  Mangle that text to make the proposal stale.
+    const preMangled = doc.getText();
+    const mangled = preMangled.replace("A PROPOSED closing paragraph.", "A reworded closing paragraph.");
+    const uri = vscode.Uri.file(path.join(WS, DOC_REL));
+    doc = await externalWriteAndReload(uri, mangled);
     await settle();
     api.proposalController.renderAll(doc);
     assert.strictEqual(api.proposalController.getStaleCount(DOC_REL), 1, "flagged stale");
@@ -143,22 +158,30 @@ suite("F4 propose/accept (host E2E — programmatic ingress, no LLM)", () => {
     assert.strictEqual(readSidecar().proposals.length, 1, "proposal still pending (recoverable)");
     // discard the husk so later tests see a clean sidecar
     assert.strictEqual(api.proposalController.rejectById(DOC_REL, id), true);
+    // Restore the file so subsequent tests can find their fixture targets:
+    // replace the optimistically-applied text back to the original fixture text.
+    const restored = preMangled.replace("A PROPOSED closing paragraph.", "A stable closing paragraph.");
+    doc = await externalWriteAndReload(uri, restored);
+    await settle();
   });
 
   test("multiple pending proposals coexist and are decidable out of order (PUC-5)", async () => {
     const doc = await openDoc();
     const api = await getApi();
-    const id1 = await proposeViaCommand(doc, "A stable opening paragraph.", "An ACCEPTED opening paragraph.", "turn-p4");
+    // Clean up any proposals left over from prior tests (F12: proposals persist in state).
-    const id2 = await proposeViaCommand(doc, "PROPOSED-BY-CLAUDE replacement sentence.", "A REPLACED-AGAIN sentence.", "turn-p5");
+    await api.proposalController.rejectAll(doc);
     await settle();
-    assert.strictEqual(api.proposalController.getRendered(DOC_REL).length, 2);
+    const id1 = await proposeViaCommand(doc, "A stable opening paragraph.", "An ACCEPTED opening paragraph.", "turn-p4");
+    const id2 = await proposeViaCommand(doc, "A stable closing paragraph.", "A REPLACED closing paragraph.", "turn-p5");
+    await settle();
+    assert.strictEqual(api.proposalController.getRendered(DOC_REL).length, 2, "two new proposals");
     // decide the SECOND first, then the first — order independence
     assert.strictEqual(await api.proposalController.acceptById(DOC_REL, id2), true);
     await settle();
     assert.strictEqual(await api.proposalController.acceptById(DOC_REL, id1), true);
     await settle();
     assert.ok(doc.getText().includes("An ACCEPTED opening paragraph."));
-    assert.ok(doc.getText().includes("A REPLACED-AGAIN sentence."));
+    assert.ok(doc.getText().includes("A REPLACED closing paragraph."));
     assert.strictEqual(api.proposalController.getRendered(DOC_REL).length, 0);
   });
 });