Files
deepseek-harness/packages/subagent/subagent-fork/tests/subagent-fork.spec.ts
T

212 lines
10 KiB
TypeScript

import { describe, expect, it } from 'vitest'
import { Context } from 'cordis'
import Loader from '@cordisjs/plugin-loader'
import LlmService from '@deepseek-ai/dsh-llm'
import SessionStore from '@deepseek-ai/dsh-session'
import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
import ToolRegistry from '@deepseek-ai/dsh-tools'
import AgentRegistry, { AgentId } from '@deepseek-ai/dsh-agent'
import AgentLoop from '@deepseek-ai/dsh-agent-loop'
import * as Invariants from '@deepseek-ai/dsh-invariants'
import SubagentService from '@deepseek-ai/dsh-subagent'
import { MockAdapter, textResponse, toolCallResponse } from '../../../core/agent-loop/tests/mock-adapter.ts'
import type { StreamChunk } from '@deepseek-ai/dsh-llm'
import * as fork from '../src/index.ts'
import { STRUCTURED_OUTPUT_TOOL } from '@deepseek-ai/dsh-subagent-inprocess'
import { completedTurnPrefix } from '../src/index.ts'
type Script = ConstructorParameters<typeof MockAdapter>[0]
/** A bare `stop` finish that streams no content → the turn ends `completed`
* with NO `assistant/message` of its own. */
const emptyStop: StreamChunk[] = [{ type: 'finish', reason: { kind: 'stop' } }]
/**
* Drives the REAL fork backend with a real loop + scripted mock MODEL + the
* real dsh-invariants plugin. The invariants plugin re-replays a seeded child
* log on `session/created` (its freeze-check), so a malformed (unbalanced) fork
* seed makes these tests THROW — that is the regression guard for the
* completed-turn-prefix boundary.
*/
async function setup(script: Script) {
const ctx = new Context()
await ctx.plugin(LlmService)
await ctx.plugin(SessionStore)
await ctx.plugin(SystemPrompt)
await ctx.plugin(ToolRegistry)
await ctx.plugin(AgentRegistry)
await ctx.plugin(Invariants)
await ctx.plugin(AgentLoop, { agents: [] })
await ctx.plugin(SubagentService)
await ctx.plugin(fork, { providerName: 'fork' })
ctx.llm.registerAdapter(['mock'], new MockAdapter(script))
const parent = ctx.agentLoop.create(AgentId('parent'), { model: 'mock' })
return { ctx, parent }
}
function text(blocks: { type: string; text?: string }[]): string {
return blocks.filter(b => b.type === 'text').map(b => b.text).join('')
}
describe('completedTurnPrefix', () => {
it('returns an empty prefix for a parent that has never completed a turn', async () => {
const { parent } = await setup([])
expect(completedTurnPrefix(parent)).toEqual([])
})
it('returns the balanced prefix up to and including the last turn/end', async () => {
const { parent } = await setup([textResponse('first'), textResponse('second')])
parent.send([{ type: 'text', text: 'q1' }])
await parent.whenIdle()
parent.send([{ type: 'text', text: 'q2' }])
await parent.whenIdle()
const prefix = completedTurnPrefix(parent)
// Ends exactly at the last turn/end; seq is contiguous from 0.
expect(prefix.at(-1)?.type).toBe('turn/end')
expect(prefix.map(e => e.seq)).toEqual(prefix.map((_, i) => i))
// Both completed turns are present.
expect(prefix.filter(e => e.type === 'turn/end')).toHaveLength(2)
})
})
describe('dsh-subagent-fork', () => {
it('forks an UNSEEDED (fresh) child when the parent has no completed turn', async () => {
// The parent has never completed a turn → empty prefix → the provider omits
// the seed → the child runs fresh. Exercises the `seed.length > 0` false arm.
const { ctx, parent } = await setup([textResponse('fresh child')])
expect(completedTurnPrefix(parent)).toEqual([])
const run = ctx.subagents.start('fork', { prompt: [{ type: 'text', text: 'child q' }], parent })
const result = await run.result
expect(result.stopReason).toBe('completed')
expect(text(result.output)).toBe('fresh child')
const child = ctx.agents.get(run.id)!
// Only the child's own turn — no seeded parent turns.
expect(child.session.events.filter(e => e.type === 'turn/end')).toHaveLength(1)
await run.dispose()
})
it('seeds the child with the parent\'s completed-turn prefix (child inherits context)', async () => {
// Parent runs one turn, then we fork. The child's seeded log should contain
// the parent's first turn, and the child should run its own new turn on top.
const { ctx, parent } = await setup([textResponse('parent answer'), textResponse('child answer')])
parent.send([{ type: 'text', text: 'parent question' }])
await parent.whenIdle()
const parentPrefixLen = parent.session.events.length
const run = ctx.subagents.start('fork', { prompt: [{ type: 'text', text: 'child question' }], parent })
const result = await run.result
expect(result.stopReason).toBe('completed')
expect(text(result.output)).toBe('child answer')
const child = ctx.agents.get(run.id)!
// The child's log STARTS with the parent's prefix (seeded), then its own turn.
expect(child.session.events.length).toBeGreaterThan(parentPrefixLen)
// The seeded prefix carried the parent's user message.
const seededUser = child.session.events.slice(0, parentPrefixLen).find(e => e.type === 'user/message')
expect(seededUser).toBeDefined()
// Lineage stamped.
expect(child.session.header.parentSession).toBe(parent.session.header.id)
// The seed boundary is recorded on the header (= the seeded prefix length),
// so a reload / replay harness can tell the inherited prefix from the
// child's own events.
expect(child.session.header.seedLength).toBe(parentPrefixLen)
await run.dispose()
})
it('produces an invariant-CLEAN seed: forking mid-turn excludes the open turn', async () => {
// Drive the parent so it has ONE completed turn, then start a SECOND turn
// that is still open (a hanging model call), and fork while it's in flight.
// The fork must seed only the completed first turn — an unbalanced seed
// would make the invariants replay throw inside ctx.subagents.start.
const { ctx, parent } = await setup([textResponse('done'), 'hang', textResponse('child')])
parent.send([{ type: 'text', text: 'q1' }])
await parent.whenIdle()
// Start a second turn that hangs (open turn/start + open step, never ends).
parent.send([{ type: 'text', text: 'q2' }])
await new Promise(r => setTimeout(r, 20)) // let the hanging turn open
// Forking now must NOT throw (the open second turn is excluded from the seed).
const run = ctx.subagents.start('fork', { prompt: [{ type: 'text', text: 'child q' }], parent })
const result = await run.result
expect(result.stopReason).toBe('completed')
expect(text(result.output)).toBe('child')
const child = ctx.agents.get(run.id)!
// The child's seed has exactly the ONE completed parent turn (the open one excluded).
const seedTurnEnds = child.session.events.filter(e => e.type === 'turn/end')
// 1 from the seeded parent turn + 1 from the child's own completed turn.
expect(seedTurnEnds.length).toBe(2)
parent.cancel()
await run.dispose()
})
it('captures structured output through the shipped plugin (seeded child, driver runtime)', async () => {
const { ctx, parent } = await setup([
textResponse('parent turn'),
toolCallResponse('c1', STRUCTURED_OUTPUT_TOOL, { answer: 9 }),
])
parent.send([{ type: 'text', text: 'warm up' }])
await parent.whenIdle()
const run = ctx.subagents.start('fork', {
prompt: [{ type: 'text', text: 'report structured' }],
parent,
outputSchema: { type: 'object', properties: { answer: { type: 'number' } }, required: ['answer'] },
})
const result = await run.result
expect(result.stopReason).toBe('completed')
expect(result.structured).toEqual({ answer: 9 })
// Run-scoped runtime: nothing stays registered after the settle.
expect(ctx.tools.get(STRUCTURED_OUTPUT_TOOL)).toBeUndefined()
await run.dispose()
})
it('does NOT return the seeded parent output when the child produces no message of its own', async () => {
// Regression: readResult must scope to the child's OWN events (after the
// seed). The parent completes a turn with a distinctive assistant message,
// then the fork child's own turn finishes with a bare `stop` and NO
// assistant/message. Scanning the whole (seeded) log would return the
// parent's "parent stale" message with stopReason 'completed'; scoped to the
// child's own events the output is empty.
const { ctx, parent } = await setup([textResponse('parent stale'), emptyStop])
parent.send([{ type: 'text', text: 'parent question' }])
await parent.whenIdle()
const run = ctx.subagents.start('fork', { prompt: [{ type: 'text', text: 'child question' }], parent })
const result = await run.result
// The child completed its own (empty) turn — completed, but with NO output
// borrowed from the seeded parent prefix.
expect(result.stopReason).toBe('completed')
expect(result.output).toEqual([])
await run.dispose()
})
it('advertises every start-time capability (depthLimit, outputSchema, toolFilter, persona)', async () => {
const { ctx } = await setup([])
expect(ctx.subagents.getProvider('fork')!.capabilities).toEqual({ outputSchema: true, depthLimit: true, toolFilter: true, persona: true })
})
it('unregisters the provider when its fiber is disposed (HMR safety)', async () => {
const ctx = new Context()
await ctx.plugin(SubagentService)
await ctx.plugin(AgentRegistry)
const fiber = await ctx.plugin(fork, { providerName: 'fork' })
expect(ctx.subagents.list()).toEqual(['fork'])
await fiber.dispose()
expect(ctx.subagents.list()).toEqual([])
})
it('has the namespace-plugin export shape (no stray default)', () => {
expect('default' in fork).toBe(false)
expect(fork.name).toBe('subagent-fork')
expect(fork.inject).toEqual(['subagents'])
const loader = Object.create(Loader.prototype) as Loader
const unwrapped = loader.unwrapExports(fork) as Record<string, unknown>
expect(unwrapped).toBe(fork)
expect(unwrapped.name).toBe('subagent-fork')
expect(unwrapped.inject).toEqual(['subagents'])
expect(typeof unwrapped.apply).toBe('function')
})
})