port: sync from Mike/pygienium@595ce48f

tests/agent-runner.test.ts

@@ -0,0 +1,137 @@
+/**
+ * agent-runner.test.ts — unit tests for the session event accumulator.
+ *
+ * `applySessionEvent` runs synchronously inside the SDK's event pipeline; a
+ * throw there crashes the host (the SDK's run-failure path re-emits events
+ * through the same callback → stack overflow), stranding run-state at the
+ * phase boundary. These tests pin the handler to never throw on the partial /
+ * malformed event shapes streaming sessions actually emit.
+ */
+import { describe, expect, it } from "bun:test";
+import {
+	applySessionEvent,
+	type SessionEventAccumulator,
+} from "../src/agent-runner.js";
+import type { AgentSessionEvent } from "@oh-my-pi/pi-coding-agent";
+
+function fresh(): SessionEventAccumulator {
+	return { text: "" };
+}
+
+/** Build a typed-as-unknown event so malformed shapes compile in tests. */
+function event(shape: unknown): AgentSessionEvent {
+	return shape as AgentSessionEvent;
+}
+
+describe("applySessionEvent", () => {
+	it("accumulates text_delta stream events in order", () => {
+		const acc = fresh();
+		applySessionEvent(
+			acc,
+			event({
+				type: "message_update",
+				assistantMessageEvent: { type: "text_delta", delta: "foo" },
+			}),
+		);
+		applySessionEvent(
+			acc,
+			event({
+				type: "message_update",
+				assistantMessageEvent: { type: "text_delta", delta: "bar" },
+			}),
+		);
+		expect(acc.text).toBe("foobar");
+	});
+
+	it("does not throw on a message_update with no assistantMessageEvent", () => {
+		const acc = fresh();
+		expect(() =>
+			applySessionEvent(acc, event({ type: "message_update" })),
+		).not.toThrow();
+		expect(acc.text).toBe("");
+	});
+
+	it("does not throw on a message_update with an unknown event shape", () => {
+		const acc = fresh();
+		expect(() => applySessionEvent(acc, event({ type: "bogus_event" }))).not.toThrow();
+		expect(() => applySessionEvent(acc, event(null))).not.toThrow();
+		expect(() => applySessionEvent(acc, event(undefined))).not.toThrow();
+		expect(acc.text).toBe("");
+	});
+
+	it("captures full text + stopReason from message_end when nothing streamed", () => {
+		const acc = fresh();
+		applySessionEvent(
+			acc,
+			event({
+				type: "message_end",
+				message: {
+					role: "assistant",
+					stopReason: "stop",
+					content: [{ type: "text", text: "full report" }],
+				},
+			}),
+		);
+		expect(acc.text).toBe("full report");
+		expect(acc.stopReason).toBe("stop");
+	});
+
+	it("does not throw on a message_end with no message", () => {
+		const acc = fresh();
+		expect(() => applySessionEvent(acc, event({ type: "message_end" }))).not.toThrow();
+		expect(acc.text).toBe("");
+	});
+
+	it("records an errorMessage surfaced on the final message", () => {
+		const acc = fresh();
+		applySessionEvent(
+			acc,
+			event({
+				type: "message_end",
+				message: { role: "assistant", errorMessage: "upstream 529" },
+			}),
+		);
+		expect(acc.errorMessage).toBe("upstream 529");
+	});
+
+	it("forwards stream-driving events and swallows a throwing forwarder", () => {
+		const originalError = console.error;
+		console.error = () => {};
+		try {
+			const forwarded: string[] = [];
+			const forward = (ev: AgentSessionEvent) => {
+				forwarded.push(ev.type);
+				if (ev.type === "tool_execution_end") throw new Error("renderer boom");
+			};
+			const acc = fresh();
+			applySessionEvent(
+				acc,
+				event({ type: "tool_execution_start", toolName: "bash" }),
+				forward,
+			);
+			applySessionEvent(
+				acc,
+				event({ type: "tool_execution_end", toolName: "bash" }),
+				forward,
+			);
+			expect(forwarded).toEqual(["tool_execution_start", "tool_execution_end"]);
+		} finally {
+			console.error = originalError;
+		}
+	});
+
+	it("does not forward non-stream-driving events", () => {
+		const forwarded: string[] = [];
+		const acc = fresh();
+		applySessionEvent(
+			acc,
+			event({ type: "message_update", assistantMessageEvent: { type: "text_delta", delta: "x" } }),
+			(ev) => forwarded.push(ev.type),
+		);
+		applySessionEvent(acc, event({ type: "agent_settled" }), (ev) =>
+			forwarded.push(ev.type),
+		);
+		expect(forwarded).toEqual([]);
+		expect(acc.text).toBe("x");
+	});
+});