fix(app): diff list normalization

packages/app/src/utils/diffs.test.ts

@@ -0,0 +1,74 @@
+import { describe, expect, test } from "bun:test"
+import type { SnapshotFileDiff } from "@opencode-ai/sdk/v2"
+import type { Message } from "@opencode-ai/sdk/v2/client"
+import { diffs, message } from "./diffs"
+
+const item = {
+  file: "src/app.ts",
+  patch: "@@ -1 +1 @@\n-old\n+new\n",
+  additions: 1,
+  deletions: 1,
+  status: "modified",
+} satisfies SnapshotFileDiff
+
+describe("diffs", () => {
+  test("keeps valid arrays", () => {
+    expect(diffs([item])).toEqual([item])
+  })
+
+  test("wraps a single diff object", () => {
+    expect(diffs(item)).toEqual([item])
+  })
+
+  test("reads keyed diff objects", () => {
+    expect(diffs({ a: item })).toEqual([item])
+  })
+
+  test("drops invalid entries", () => {
+    expect(
+      diffs([
+        item,
+        { file: "src/bad.ts", additions: 1, deletions: 1 },
+        { patch: item.patch, additions: 1, deletions: 1 },
+      ]),
+    ).toEqual([item])
+  })
+})
+
+describe("message", () => {
+  test("normalizes user summaries with object diffs", () => {
+    const input = {
+      id: "msg_1",
+      sessionID: "ses_1",
+      role: "user",
+      time: { created: 1 },
+      agent: "build",
+      model: { providerID: "openai", modelID: "gpt-5" },
+      summary: {
+        title: "Edit",
+        diffs: { a: item },
+      },
+    } as unknown as Message
+
+    expect(message(input)).toMatchObject({
+      summary: {
+        title: "Edit",
+        diffs: [item],
+      },
+    })
+  })
+
+  test("drops invalid user summaries", () => {
+    const input = {
+      id: "msg_1",
+      sessionID: "ses_1",
+      role: "user",
+      time: { created: 1 },
+      agent: "build",
+      model: { providerID: "openai", modelID: "gpt-5" },
+      summary: true,
+    } as unknown as Message
+
+    expect(message(input)).toMatchObject({ summary: undefined })
+  })
+})