test(transaction): add interleaved history isolation coverage

2026-04-14 16:43:00 +10:00
parent 226a6eef0a
commit 5cd609cea7
3 changed files with 533 additions and 1 deletions
@@ -0,0 +1,125 @@
+import { arrayToMap } from "@excalidraw/common";
+import { API } from "@excalidraw/excalidraw/tests/helpers/api";
+
+import {
+  DEFAULT_TRANSACTION_MERGE_POLICY,
+  TransactionLedger,
+  collectChangedElementIds,
+} from "../src";
+
+import type { ExcalidrawElement } from "../src/types";
+
+describe("TransactionLedger", () => {
+  it("ignores metadata-only changes when collecting changed ids", () => {
+    const before = API.createElement({
+      type: "rectangle",
+      id: "rect-1",
+    });
+    const after = {
+      ...before,
+      version: before.version + 1,
+      versionNonce: before.versionNonce + 1,
+      seed: before.seed + 1,
+      updated: before.updated + 1,
+      index: "a2" as ExcalidrawElement["index"],
+    };
+
+    expect(
+      collectChangedElementIds(arrayToMap([before]), arrayToMap([after])),
+    ).toEqual([]);
+  });
+
+  it("drops ledger entry when element is created and deleted in one transaction", () => {
+    const ledger = new TransactionLedger();
+    const created = API.createElement({
+      type: "rectangle",
+      id: "rect-1",
+    });
+
+    ledger.recordStep(new Map(), arrayToMap([created]));
+    expect(ledger.hasEntries()).toBe(true);
+
+    ledger.recordStep(arrayToMap([created]), new Map());
+    expect(ledger.hasEntries()).toBe(false);
+  });
+
+  it("materializes create operation when live scene still matches target", () => {
+    const ledger = new TransactionLedger();
+    const created = API.createElement({
+      type: "rectangle",
+      id: "rect-1",
+      strokeColor: "#ff006e",
+    });
+
+    ledger.recordStep(new Map(), arrayToMap([created]));
+
+    const { logicalBefore, logicalAfter } = ledger.buildSyntheticSnapshots(
+      arrayToMap([created]),
+      DEFAULT_TRANSACTION_MERGE_POLICY,
+    );
+
+    expect(logicalBefore.has(created.id)).toBe(false);
+    expect(logicalAfter.get(created.id)?.strokeColor).toBe("#ff006e");
+  });
+
+  it("skips conflicting update when policy is live-wins", () => {
+    const ledger = new TransactionLedger();
+    const baseline = API.createElement({
+      type: "rectangle",
+      id: "rect-1",
+      strokeColor: "#000000",
+    });
+    const target = {
+      ...baseline,
+      strokeColor: "#ff006e",
+      version: baseline.version + 1,
+    };
+    const live = {
+      ...target,
+      strokeColor: "#3a86ff",
+      version: target.version + 1,
+    };
+
+    ledger.recordStep(arrayToMap([baseline]), arrayToMap([target]));
+
+    const { logicalBefore, logicalAfter } = ledger.buildSyntheticSnapshots(
+      arrayToMap([live]),
+      DEFAULT_TRANSACTION_MERGE_POLICY,
+    );
+
+    expect(logicalBefore.get(live.id)?.strokeColor).toBe("#3a86ff");
+    expect(logicalAfter.get(live.id)?.strokeColor).toBe("#3a86ff");
+  });
+
+  it("applies conflicting update when policy is transaction-wins", () => {
+    const ledger = new TransactionLedger();
+    const baseline = API.createElement({
+      type: "rectangle",
+      id: "rect-1",
+      strokeColor: "#000000",
+    });
+    const target = {
+      ...baseline,
+      strokeColor: "#ff006e",
+      version: baseline.version + 1,
+    };
+    const live = {
+      ...target,
+      strokeColor: "#3a86ff",
+      version: target.version + 1,
+    };
+
+    ledger.recordStep(arrayToMap([baseline]), arrayToMap([target]));
+
+    const { logicalBefore, logicalAfter } = ledger.buildSyntheticSnapshots(
+      arrayToMap([live]),
+      {
+        ...DEFAULT_TRANSACTION_MERGE_POLICY,
+        conflictWinner: "transaction",
+      },
+    );
+
+    expect(logicalBefore.get(live.id)?.strokeColor).toBe("#000000");
+    expect(logicalAfter.get(live.id)?.strokeColor).toBe("#ff006e");
+  });
+});