test(agents): share assistant error message test fixture

src/agents/test-helpers/assistant-message-fixtures.ts

@@ -0,0 +1,34 @@
+import type { AssistantMessage } from "@mariozechner/pi-ai";
+
+const ZERO_USAGE: AssistantMessage["usage"] = {
+  input: 0,
+  output: 0,
+  cacheRead: 0,
+  cacheWrite: 0,
+  totalTokens: 0,
+  cost: {
+    input: 0,
+    output: 0,
+    cacheRead: 0,
+    cacheWrite: 0,
+    total: 0,
+  },
+};
+
+export function makeAssistantMessageFixture(
+  overrides: Partial<AssistantMessage> = {},
+): AssistantMessage {
+  const errorText = typeof overrides.errorMessage === "string" ? overrides.errorMessage : "error";
+  return {
+    role: "assistant",
+    api: "openai-responses",
+    provider: "openai",
+    model: "test-model",
+    usage: ZERO_USAGE,
+    timestamp: 0,
+    stopReason: "error",
+    errorMessage: errorText,
+    content: [{ type: "text", text: errorText }],
+    ...overrides,
+  };
+}