源码快照 @ 2026-09-02 (source-only, 剔除非源码素材)

apps/app/tests/markdown-selection-stability.test.ts

@@ -0,0 +1,55 @@
+import { describe, expect, test } from "bun:test";
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+
+import { selectionIntersectsElement } from "../src/components/markdown/selection-stability";
+
+const root = {} as Element;
+
+function selection(input: {
+  collapsed?: boolean;
+  intersections: Array<boolean | Error>;
+}) {
+  return {
+    isCollapsed: input.collapsed ?? false,
+    rangeCount: input.intersections.length,
+    getRangeAt(index: number) {
+      const intersection = input.intersections[index];
+      return {
+        intersectsNode(node: Node) {
+          expect(node).toBe(root);
+          if (intersection instanceof Error) throw intersection;
+          return intersection;
+        },
+      } as Range;
+    },
+  } as Pick<Selection, "getRangeAt" | "isCollapsed" | "rangeCount">;
+}
+
+describe("markdown selection stability", () => {
+  test("recognizes a live range that intersects rendered markdown", () => {
+    expect(selectionIntersectsElement(root, selection({ intersections: [false, true] }))).toBe(true);
+  });
+
+  test("does not defer updates for a collapsed caret or an empty selection", () => {
+    expect(selectionIntersectsElement(root, selection({ collapsed: true, intersections: [true] }))).toBe(false);
+    expect(selectionIntersectsElement(root, null)).toBe(false);
+  });
+
+  test("ignores a detached stale range and continues checking live ranges", () => {
+    expect(selectionIntersectsElement(root, selection({ intersections: [new Error("detached"), true] }))).toBe(true);
+  });
+
+  test("keeps the innerHTML prop stable across unrelated completed-response renders", () => {
+    const sources = [
+      "../src/components/markdown/markdown.tsx",
+      "../src/react-app/domains/session/surface/markdown.tsx",
+    ].map((path) => readFileSync(join(import.meta.dir, path), "utf8"));
+
+    for (const source of sources) {
+      expect(source).toContain("const stableInnerHtml = useMemo(() => ({ __html: html }), [html]);");
+      expect(source).toContain("dangerouslySetInnerHTML={stableInnerHtml}");
+      expect(source).not.toContain("dangerouslySetInnerHTML={{ __html: html }}");
+    }
+  });
+});