shiro-neko/test/session-features.test.ts

import { expect, test } from 'bun:test';
import { MockLanguageModelV4, simulateReadableStream } from 'ai/test';
import type { LanguageModelV4CallOptions, LanguageModelV4StreamPart } from '@ai-sdk/provider';
import { variantByName } from '../src/agents';
import { Memory } from '../src/memory';
import { createHost } from '../src/plugins';
import { guardPlugin, timePlugin } from '../src/plugins-builtin';
import { Session } from '../src/session';
import { loadSkills } from '../src/skills';

const usage = {
  inputTokens: { total: 5, noCache: 5, cacheRead: 0, cacheWrite: 0 },
  outputTokens: { total: 2 },
} as any;

const stream = (parts: LanguageModelV4StreamPart[]) => ({
  stream: simulateReadableStream({ chunks: parts, chunkDelayInMs: null, initialDelayInMs: null }),
});

const toolCall = (id: string, toolName: string, input: unknown): LanguageModelV4StreamPart[] => [
  { type: 'tool-input-start', id, toolName },
  { type: 'tool-input-end', id },
  { type: 'tool-call', toolCallId: id, toolName, input: JSON.stringify(input) },
  { type: 'finish', finishReason: { unified: 'tool-calls', raw: 'tool_use' }, usage },
];

const text = (body: string): LanguageModelV4StreamPart[] => [
  { type: 'text-start', id: '0' },
  { type: 'text-delta', id: '0', delta: body },
  { type: 'text-end', id: '0' },
  { type: 'finish', finishReason: { unified: 'stop', raw: 'stop' }, usage },
];

function recorder() {
  const seen: LanguageModelV4CallOptions[] = [];
  const model = new MockLanguageModelV4({
    doStream: async (o) => {
      seen.push(o);
      return stream(text('ok'));
    },
  });
  return { seen, model };
}

test('the thinking level reaches the provider call', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', agent: variantByName('deep') });
  for await (const _ of session.send('hi')) void _;
  expect(seen[0]?.reasoning).toBe('xhigh');
});

test('the quick variant asks for no thinking at all', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', agent: variantByName('quick') });
  for await (const _ of session.send('hi')) void _;
  expect(seen[0]?.reasoning).toBe('none');
});

test('switching the agent mid-session changes the next call', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny' });

  for await (const _ of session.send('first')) void _;
  expect(seen[0]?.reasoning).toBe('medium');

  session.setAgent(variantByName('deep')!);
  for await (const _ of session.send('second')) void _;
  expect(seen[1]?.reasoning).toBe('xhigh');
});

test('a read-only variant hides the mutating tools from the model', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', agent: variantByName('plan') });
  for await (const _ of session.send('investigate')) void _;

  const offered = (seen[0]?.tools ?? []).map((t) => t.name);
  expect(offered).toContain('read_file');
  expect(offered).toContain('grep');
  expect(offered).not.toContain('write_file');
  expect(offered).not.toContain('edit_file');
  expect(offered).not.toContain('bash');
});

test('the default variant offers everything', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny' });
  for await (const _ of session.send('go')) void _;

  const offered = (seen[0]?.tools ?? []).map((t) => t.name);
  expect(offered).toContain('bash');
  expect(offered).toContain('write_file');
});

test('the variant appendix reaches the system prompt', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', agent: variantByName('review') });
  for await (const _ of session.send('review it')) void _;

  expect(JSON.stringify(seen[0]?.prompt.find((m) => m.role === 'system'))).toContain('reviewing code');
});

test('a variant maxSteps overrides the session default', async () => {
  const { model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', agent: variantByName('quick'), maxSteps: 99 });
  expect(session.agent().maxSteps).toBe(12);
});

test('the skill catalogue and skill tool are offered when skills are loaded', async () => {
  const { seen, model } = recorder();
  const skills = await loadSkills(process.cwd());
  const session = new Session({ model, askApproval: async () => 'deny', skills });
  for await (const _ of session.send('hi')) void _;

  expect((seen[0]?.tools ?? []).map((t) => t.name)).toContain('skill');
  const system = JSON.stringify(seen[0]?.prompt.find((m) => m.role === 'system'));
  expect(system).toContain('debug');
  expect(system).toContain('Skills available');
});

test('no skill tool is offered when there are no skills', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', skills: [] });
  for await (const _ of session.send('hi')) void _;
  expect((seen[0]?.tools ?? []).map((t) => t.name)).not.toContain('skill');
});

test('the skill tool never needs approval', async () => {
  let n = 0;
  const skills = await loadSkills(process.cwd());
  const session = new Session({
    model: new MockLanguageModelV4({
      doStream: async () => (n++ === 0 ? stream(toolCall('c1', 'skill', { name: 'debug' })) : stream(text('loaded'))),
    }),
    askApproval: async () => {
      throw new Error('skill must not prompt');
    },
    skills,
  });

  const kinds: string[] = [];
  for await (const ev of session.send('debug this')) kinds.push(ev.type);
  expect(kinds).toContain('tool-result');
  expect(kinds).not.toContain('tool-denied');
});

test('memory tools are offered and never prompt', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', memory: new Memory('/repo-test') });
  for await (const _ of session.send('hi')) void _;

  const offered = (seen[0]?.tools ?? []).map((t) => t.name);
  expect(offered).toContain('remember');
  expect(offered).toContain('recall');
  expect(offered).toContain('forget');
});

test('plugin tools reach the model and are auto-approved', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', plugins: createHost([timePlugin]) });
  for await (const _ of session.send('what time is it')) void _;
  expect((seen[0]?.tools ?? []).map((t) => t.name)).toContain('current_time');
});

test('the plugin appendix reaches the system prompt', async () => {
  const { seen, model } = recorder();
  const session = new Session({ model, askApproval: async () => 'deny', plugins: createHost([guardPlugin]) });
  for await (const _ of session.send('hi')) void _;
  expect(JSON.stringify(seen[0]?.prompt.find((m) => m.role === 'system'))).toContain('refuses irreversible');
});

test('the guard blocks a destructive bash call without asking the user', async () => {
  let asked = 0;
  let n = 0;
  const session = new Session({
    model: new MockLanguageModelV4({
      doStream: async () =>
        n++ === 0 ? stream(toolCall('c1', 'bash', { command: 'rm -rf /' })) : stream(text('understood')),
    }),
    askApproval: async () => {
      asked++;
      return 'once';
    },
    plugins: createHost([guardPlugin]),
  });

  const events: string[] = [];
  const notices: string[] = [];
  for await (const ev of session.send('clean up')) {
    events.push(ev.type);
    if (ev.type === 'notice') notices.push(ev.text);
  }

  expect(asked).toBe(0);
  expect(events).toContain('notice');
  expect(events).toContain('tool-denied');
  expect(notices.join()).toContain('recursive or forced delete');
});

test('a safe bash call still reaches the approval prompt', async () => {
  let asked = 0;
  let n = 0;
  const session = new Session({
    model: new MockLanguageModelV4({
      doStream: async () => (n++ === 0 ? stream(toolCall('c1', 'bash', { command: 'echo hi' })) : stream(text('done'))),
    }),
    askApproval: async () => {
      asked++;
      return 'once';
    },
    plugins: createHost([guardPlugin]),
  });

  for await (const _ of session.send('say hi')) void _;
  expect(asked).toBe(1);
});

test('afterTurn fires once the turn ends', async () => {
  let fired = 0;
  const { model } = recorder();
  const session = new Session({
    model,
    askApproval: async () => 'deny',
    plugins: createHost([{ name: 'counter', description: '', afterTurn: () => void fired++ }]),
  });

  for await (const _ of session.send('hi')) void _;
  expect(fired).toBe(1);
});