fix(sequentialthinking): harden thought-box rendering and validation

src/sequentialthinking/__tests__/index.test.ts

@@ -0,0 +1,112 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+import { handleSequentialThinkingTool } from '../index.js';
+import { SequentialThinkingServer } from '../lib.js';
+
+// Silence the chalk-styled stderr boxes during tests.
+vi.mock('chalk', () => {
+  const id = (str: string) => str;
+  return { default: { yellow: id, green: id, blue: id } };
+});
+
+describe('handleSequentialThinkingTool', () => {
+  let thinking: SequentialThinkingServer;
+
+  beforeEach(() => {
+    process.env.DISABLE_THOUGHT_LOGGING = 'true';
+    thinking = new SequentialThinkingServer();
+  });
+
+  it('returns content + structuredContent on a successful call', async () => {
+    const result = await handleSequentialThinkingTool(thinking, {
+      thought: 'analyze',
+      thoughtNumber: 1,
+      totalThoughts: 3,
+      nextThoughtNeeded: true,
+    });
+
+    // Pass-through of the underlying content array, plus a parsed
+    // structuredContent matching the registered outputSchema.
+    expect(result).toHaveProperty('content');
+    expect(result).toHaveProperty('structuredContent');
+
+    const sc = (result as { structuredContent: Record<string, unknown> }).structuredContent;
+    expect(sc).toMatchObject({
+      thoughtNumber: 1,
+      totalThoughts: 3,
+      nextThoughtNeeded: true,
+      thoughtHistoryLength: 1,
+    });
+    expect(Array.isArray(sc.branches)).toBe(true);
+  });
+
+  it('passes through isError results without trying to parse structured content', async () => {
+    // Force the underlying call to fail by having the formatter throw on
+    // its console.error step. (Logging is enabled inside processThought.)
+    delete process.env.DISABLE_THOUGHT_LOGGING;
+    thinking = new SequentialThinkingServer();
+    const errSpy = vi.spyOn(console, 'error').mockImplementation(() => {
+      throw new Error('stderr unavailable');
+    });
+
+    const result = await handleSequentialThinkingTool(thinking, {
+      thought: 'will explode',
+      thoughtNumber: 1,
+      totalThoughts: 1,
+      nextThoughtNeeded: false,
+    });
+
+    errSpy.mockRestore();
+    process.env.DISABLE_THOUGHT_LOGGING = 'true';
+
+    expect(result).toHaveProperty('isError', true);
+    // Crucially, NOT structuredContent — that would imply a successful parse
+    // and the SDK shouldn't see a half-formed response on the error branch.
+    expect(result).not.toHaveProperty('structuredContent');
+  });
+
+  it('reflects auto-adjusted totalThoughts in structuredContent', async () => {
+    const result = await handleSequentialThinkingTool(thinking, {
+      thought: 'jump ahead',
+      thoughtNumber: 5,
+      totalThoughts: 3, // less than thoughtNumber: should be bumped to 5
+      nextThoughtNeeded: true,
+    });
+
+    const sc = (result as { structuredContent: Record<string, unknown> }).structuredContent;
+    expect(sc.totalThoughts).toBe(5);
+  });
+
+  it('returns an isError response when isRevision is set without revisesThought', async () => {
+    const result = await handleSequentialThinkingTool(thinking, {
+      thought: 'oops',
+      thoughtNumber: 2,
+      totalThoughts: 2,
+      nextThoughtNeeded: false,
+      isRevision: true,
+    });
+
+    expect(result).toMatchObject({ isError: true });
+    expect(result).not.toHaveProperty('structuredContent');
+    const text = (result as { content: { text: string }[] }).content[0].text;
+    expect(JSON.parse(text)).toMatchObject({
+      status: 'failed',
+      error: expect.stringMatching(/revisesThought is required/),
+    });
+  });
+
+  it('returns an isError response when branchFromThought is set without branchId', async () => {
+    const result = await handleSequentialThinkingTool(thinking, {
+      thought: 'oops',
+      thoughtNumber: 2,
+      totalThoughts: 2,
+      nextThoughtNeeded: false,
+      branchFromThought: 1,
+    });
+
+    expect(result).toMatchObject({ isError: true });
+    const text = (result as { content: { text: string }[] }).content[0].text;
+    expect(JSON.parse(text)).toMatchObject({
+      error: expect.stringMatching(/branchId is required/),
+    });
+  });
+});