From b705d62fd14e90342cb0aec2ff6b424ca04b9e89 Mon Sep 17 00:00:00 2001
From: Molecule AI Core-FE <core-fe@agents.moleculesai.app>
Date: Tue, 12 May 2026 14:45:18 +0000
Subject: [PATCH] =?UTF-8?q?test(chat):=20add=20extractAgentText=20coverage?=
 =?UTF-8?q?=20=E2=80=94=206=20cases?=
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Covers the 4 unique branches not exercised by extractTextsFromParts:
artifacts[0].parts fallback, status.message.parts fallback, bare-string
passthrough, and the try/catch sentinel on null input.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
---
 .../chat/__tests__/message-parser.test.ts     | 35 +++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/canvas/src/components/tabs/chat/__tests__/message-parser.test.ts b/canvas/src/components/tabs/chat/__tests__/message-parser.test.ts
index 3a4748a7..e33af39e 100644
--- a/canvas/src/components/tabs/chat/__tests__/message-parser.test.ts
+++ b/canvas/src/components/tabs/chat/__tests__/message-parser.test.ts
@@ -281,6 +281,41 @@ describe("extractTextsFromParts", () => {
   });
 });
 
+describe("extractAgentText", () => {
+  it("extracts from task.parts via extractTextsFromParts", () => {
+    const task = { parts: [{ kind: "text", text: "Agent reply" }] };
+    expect(extractAgentText(task)).toBe("Agent reply");
+  });
+
+  it("falls back to artifacts[0].parts when task.parts is absent", () => {
+    const task = {
+      artifacts: [{ parts: [{ kind: "text", text: "Artifact text" }] }],
+    };
+    expect(extractAgentText(task)).toBe("Artifact text");
+  });
+
+  it("falls back to status.message.parts when both parts and artifacts are absent", () => {
+    const task = {
+      status: { message: { parts: [{ kind: "text", text: "Status text" }] } },
+    };
+    expect(extractAgentText(task)).toBe("Status text");
+  });
+
+  it("returns the task as-is when it is a bare string", () => {
+    expect(extractAgentText("Bare string response")).toBe("Bare string response");
+  });
+
+  it("returns sentinel when nothing extractable is present", () => {
+    expect(extractAgentText({})).toBe("(Could not extract response text)");
+  });
+
+  it("returns sentinel for null input (caught by try/catch)", () => {
+    expect(extractAgentText(null as unknown as Record<string, unknown>)).toBe(
+      "(Failed to parse response)"
+    );
+  });
+});
+
 describe("extractFilesFromTask", () => {
   it("pulls A2A file parts out of a result", () => {
     const task = {