fix: collapse session fork to one api
This commit is contained in:
Hypatia May
@@ -10,13 +10,26 @@ async function setup(): Promise<{ ctx: Context; sessions: SessionStore }> {
|
||||
return { ctx, sessions: ctx.sessions }
|
||||
}
|
||||
|
||||
function appendClosedTurn(session: Session, reason: TurnEndReason = { kind: 'completed' }): void {
|
||||
session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
function appendClosedTurn(
|
||||
session: Session,
|
||||
turn: number,
|
||||
text = `hello ${turn}`,
|
||||
reason: TurnEndReason = { kind: 'completed' },
|
||||
): void {
|
||||
session.append('turn/start', { turn, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
session.append('user/message', {
|
||||
content: [{ type: 'text', text: 'hello' }],
|
||||
content: [{ type: 'text', text }],
|
||||
source: { kind: 'user' },
|
||||
}, { surfaceOp: 'append' })
|
||||
session.append('turn/end', { turn, reason })
|
||||
}
|
||||
|
||||
function appendOpenTurn(session: Session, turn: number): void {
|
||||
session.append('turn/start', { turn, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
session.append('user/message', {
|
||||
content: [{ type: 'text', text: `open ${turn}` }],
|
||||
source: { kind: 'user' },
|
||||
}, { surfaceOp: 'append' })
|
||||
session.append('turn/end', { turn: 1, reason })
|
||||
}
|
||||
|
||||
function firstUserMessage(events: readonly SessionEvent[]): SessionEvent<'user/message'> {
|
||||
@@ -25,43 +38,68 @@ function firstUserMessage(events: readonly SessionEvent[]): SessionEvent<'user/m
|
||||
return event
|
||||
}
|
||||
|
||||
describe('SessionStore fork helpers', () => {
|
||||
it('snapshots an empty live session as an empty seed with lineage metadata', async () => {
|
||||
function lastSeq(session: Session): number {
|
||||
const event = session.events.at(-1)
|
||||
if (event === undefined) throw new Error('missing last event')
|
||||
return event.seq
|
||||
}
|
||||
|
||||
describe('SessionStore.fork', () => {
|
||||
it('forks an empty live session as an empty child with lineage metadata', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('empty-parent'), { meta: { cwd: '/workspace' } })
|
||||
|
||||
const snapshot = sessions.snapshot(source)
|
||||
const child = sessions.fork({ source, childSessionId: SessionId('empty-child') })
|
||||
|
||||
expect(snapshot.source).toBe(source)
|
||||
expect(snapshot.seed).toEqual([])
|
||||
expect(snapshot.meta).toEqual({
|
||||
expect(child.events).toEqual([])
|
||||
expect(child.header).toMatchObject({
|
||||
id: SessionId('empty-child'),
|
||||
cwd: '/workspace',
|
||||
parentSession: SessionId('empty-parent'),
|
||||
seedLength: 0,
|
||||
})
|
||||
})
|
||||
|
||||
it('snapshots a completed boundary by live session id and deep-clones seed events', async () => {
|
||||
it('forks the latest completed boundary by default and deep-clones seed events', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('parent'), { meta: { cwd: '/workspace' } })
|
||||
appendClosedTurn(source)
|
||||
appendClosedTurn(source, 1, 'hello')
|
||||
|
||||
const snapshot = sessions.snapshot(SessionId('parent'))
|
||||
const child = sessions.fork({ source: SessionId('parent'), childSessionId: SessionId('child') })
|
||||
|
||||
expect(snapshot.source).toBe(source)
|
||||
expect(snapshot.seed).toEqual(source.events)
|
||||
expect(snapshot.seed).not.toBe(source.events)
|
||||
expect(snapshot.seed[1]).not.toBe(source.events[1])
|
||||
firstUserMessage(snapshot.seed).data.content[0] = { type: 'text', text: 'mutated' }
|
||||
expect(child.events).toEqual(source.events)
|
||||
expect(child.events).not.toBe(source.events)
|
||||
expect(child.events[1]).not.toBe(source.events[1])
|
||||
firstUserMessage(child.events).data.content[0] = { type: 'text', text: 'child mutation' }
|
||||
expect(firstUserMessage(source.events).data.content).toEqual([{ type: 'text', text: 'hello' }])
|
||||
expect(snapshot.meta).toEqual({
|
||||
expect(child.header).toMatchObject({
|
||||
id: SessionId('child'),
|
||||
cwd: '/workspace',
|
||||
parentSession: SessionId('parent'),
|
||||
seedLength: source.events.length,
|
||||
})
|
||||
})
|
||||
|
||||
it('accepts every turn/end reason as a fork boundary', async () => {
|
||||
it('forks from an earlier turn boundary even when the source currently has an open tail', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('parent'), { meta: { cwd: '/workspace' } })
|
||||
appendClosedTurn(source, 1, 'first')
|
||||
const firstBoundary = lastSeq(source)
|
||||
appendClosedTurn(source, 2, 'second')
|
||||
appendOpenTurn(source, 3)
|
||||
|
||||
const child = sessions.fork({
|
||||
source,
|
||||
boundary: firstBoundary,
|
||||
childSessionId: SessionId('child-from-first'),
|
||||
})
|
||||
|
||||
expect(child.events).toEqual(source.events.slice(0, firstBoundary + 1))
|
||||
expect(child.header.seedLength).toBe(firstBoundary + 1)
|
||||
expect(child.deriveMessages()).toEqual([{ role: 'user', content: [{ type: 'text', text: 'first' }] }])
|
||||
})
|
||||
|
||||
it('accepts every turn/end reason as an explicit fork boundary', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const reasons: TurnEndReason[] = [
|
||||
{ kind: 'completed' },
|
||||
@@ -74,19 +112,42 @@ describe('SessionStore fork helpers', () => {
|
||||
|
||||
for (const reason of reasons) {
|
||||
const source = ctx.sessions.create(SessionId(`parent-${reason.kind}`))
|
||||
appendClosedTurn(source, reason)
|
||||
appendClosedTurn(source, 1, reason.kind, reason)
|
||||
|
||||
const snapshot = sessions.snapshot(source)
|
||||
const child = sessions.fork({
|
||||
source,
|
||||
boundary: lastSeq(source),
|
||||
childSessionId: SessionId(`child-${reason.kind}`),
|
||||
})
|
||||
|
||||
expect(snapshot.seed.at(-1)?.type).toBe('turn/end')
|
||||
expect(snapshot.meta.seedLength).toBe(source.events.length)
|
||||
expect(child.events.at(-1)?.type).toBe('turn/end')
|
||||
expect(child.header.seedLength).toBe(source.events.length)
|
||||
}
|
||||
})
|
||||
|
||||
it('rejects invalid boundaries before creating a child', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const empty = ctx.sessions.create(SessionId('empty'))
|
||||
expect(() => sessions.fork({ source: empty, boundary: 0, childSessionId: SessionId('empty-child') }))
|
||||
.toThrow(new SessionForkError('fork boundary 0 does not exist in session "empty" (last seq: none)', 'INVALID_BOUNDARY'))
|
||||
expect(ctx.sessions.get(SessionId('empty-child'))).toBeUndefined()
|
||||
|
||||
const source = ctx.sessions.create(SessionId('parent'))
|
||||
appendClosedTurn(source, 1)
|
||||
expect(() => sessions.fork({ source, boundary: -1, childSessionId: SessionId('negative') }))
|
||||
.toThrow(/non-negative safe integer/)
|
||||
expect(() => sessions.fork({ source, boundary: 0.5, childSessionId: SessionId('fraction') }))
|
||||
.toThrow(/non-negative safe integer/)
|
||||
expect(() => sessions.fork({ source, boundary: Number.MAX_SAFE_INTEGER + 1, childSessionId: SessionId('unsafe') }))
|
||||
.toThrow(/non-negative safe integer/)
|
||||
expect(() => sessions.fork({ source, boundary: source.seq, childSessionId: SessionId('past-end') }))
|
||||
.toThrow(new SessionForkError(`fork boundary ${source.seq} does not exist in session "parent" (last seq: ${source.seq - 1})`, 'INVALID_BOUNDARY'))
|
||||
})
|
||||
|
||||
it('rejects an unknown live session id', async () => {
|
||||
const { sessions } = await setup()
|
||||
|
||||
expect(() => sessions.snapshot(SessionId('missing')))
|
||||
expect(() => sessions.fork({ source: SessionId('missing') }))
|
||||
.toThrow(new SessionForkError('session "missing" not found', 'SESSION_NOT_FOUND'))
|
||||
})
|
||||
|
||||
@@ -94,7 +155,7 @@ describe('SessionStore fork helpers', () => {
|
||||
const { sessions } = await setup()
|
||||
const detached = new Session(SessionId('detached'))
|
||||
|
||||
expect(() => sessions.snapshot(detached))
|
||||
expect(() => sessions.fork({ source: detached }))
|
||||
.toThrow(new SessionForkError('session "detached" not found', 'SESSION_NOT_FOUND'))
|
||||
})
|
||||
|
||||
@@ -103,28 +164,32 @@ describe('SessionStore fork helpers', () => {
|
||||
ctx.sessions.create(SessionId('same-id'))
|
||||
const stale = new Session(SessionId('same-id'))
|
||||
|
||||
expect(() => sessions.snapshot(stale))
|
||||
expect(() => sessions.fork({ source: stale }))
|
||||
.toThrow(new SessionForkError('session "same-id" is not the live store instance', 'SESSION_NOT_LIVE'))
|
||||
})
|
||||
|
||||
it('rejects non-empty logs whose last event is not turn/end', async () => {
|
||||
it('rejects selected slices whose boundary is inside an open turn', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const cases: [string, (session: Session) => void][] = [
|
||||
const cases: [string, (session: Session) => number][] = [
|
||||
['turn/start', (session) => {
|
||||
session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
return lastSeq(session)
|
||||
}],
|
||||
['step/start', (session) => {
|
||||
session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
session.append('step/start', { turn: 1, step: 1 })
|
||||
return lastSeq(session)
|
||||
}],
|
||||
['user/message', (session) => {
|
||||
session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
session.append('user/message', { content: [{ type: 'text', text: 'open' }], source: { kind: 'user' } }, { surfaceOp: 'append' })
|
||||
return lastSeq(session)
|
||||
}],
|
||||
['assistant/message', (session) => {
|
||||
session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
session.append('step/start', { turn: 1, step: 1 })
|
||||
session.append('assistant/message', { turn: 1, step: 1, content: [{ type: 'text', text: 'partial' }] }, { surfaceOp: 'append' })
|
||||
return lastSeq(session)
|
||||
}],
|
||||
['tool/call', (session) => {
|
||||
const callId = CallId('call-open')
|
||||
@@ -136,51 +201,64 @@ describe('SessionStore fork helpers', () => {
|
||||
content: [{ type: 'tool-call', id: callId, name: 'bash', arguments: '{}' }],
|
||||
}, { surfaceOp: 'append' })
|
||||
session.append('tool/call', { turn: 1, step: 1, callId, name: 'bash', arguments: '{}' })
|
||||
return lastSeq(session)
|
||||
}],
|
||||
]
|
||||
|
||||
for (const [lastType, build] of cases) {
|
||||
const source = ctx.sessions.create(SessionId(`open-${lastType}`))
|
||||
build(source)
|
||||
const boundary = build(source)
|
||||
|
||||
expect(() => sessions.snapshot(source))
|
||||
.toThrow(new SessionForkError(`cannot fork session "open-${lastType}" inside an open turn (last event: ${lastType})`, 'OPEN_TURN'))
|
||||
expect(() => sessions.fork({ source, boundary }))
|
||||
.toThrow(new SessionForkError(`cannot fork session "open-${lastType}" at boundary ${boundary}: slice ends inside an open turn (last event: ${lastType})`, 'OPEN_TURN'))
|
||||
}
|
||||
})
|
||||
|
||||
it('creates a forked child session with the seed and lineage metadata', async () => {
|
||||
it('rejects malformed turn enclosure in the selected slice', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('parent'), { meta: { cwd: '/workspace' } })
|
||||
appendClosedTurn(source)
|
||||
const outside = ctx.sessions.create(SessionId('outside'), {
|
||||
seed: [
|
||||
{ type: 'step/start', seq: 0, time: 1, data: { turn: 1, step: 1 } },
|
||||
],
|
||||
})
|
||||
expect(() => sessions.fork({ source: outside, boundary: 0 }))
|
||||
.toThrow(new SessionForkError('cannot fork session "outside" at boundary 0: event 0 (step/start) is outside a turn', 'OPEN_TURN'))
|
||||
|
||||
const child = sessions.fork({ source, sessionId: SessionId('child') })
|
||||
const nested = ctx.sessions.create(SessionId('nested'), {
|
||||
seed: [
|
||||
{ type: 'turn/start', seq: 0, time: 1, data: { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } } },
|
||||
{ type: 'turn/start', seq: 1, time: 2, data: { turn: 2, trigger: { kind: 'message', source: { kind: 'user' } } } },
|
||||
],
|
||||
})
|
||||
expect(() => sessions.fork({ source: nested, boundary: 1 }))
|
||||
.toThrow(new SessionForkError('cannot fork session "nested" at boundary 1: turn 2 starts before turn 1 ended', 'OPEN_TURN'))
|
||||
|
||||
expect(child.id).toBe(SessionId('child'))
|
||||
expect(child.events).toEqual(source.events)
|
||||
expect(child.header.parentSession).toBe(source.id)
|
||||
expect(child.header.seedLength).toBe(source.events.length)
|
||||
expect(child.header.cwd).toBe('/workspace')
|
||||
firstUserMessage(child.events).data.content[0] = { type: 'text', text: 'child mutation' }
|
||||
expect(firstUserMessage(source.events).data.content).toEqual([{ type: 'text', text: 'hello' }])
|
||||
const orphanEnd = ctx.sessions.create(SessionId('orphan-end'), {
|
||||
seed: [
|
||||
{ type: 'turn/end', seq: 0, time: 1, data: { turn: 1, reason: { kind: 'completed' } } },
|
||||
],
|
||||
})
|
||||
expect(() => sessions.fork({ source: orphanEnd, boundary: 0 }))
|
||||
.toThrow(new SessionForkError('cannot fork session "orphan-end" at boundary 0: turn/end at seq 0 has no matching turn/start', 'OPEN_TURN'))
|
||||
})
|
||||
|
||||
it('rejects a child session id that is already live with a typed fork error', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('parent'))
|
||||
appendClosedTurn(source)
|
||||
appendClosedTurn(source, 1)
|
||||
ctx.sessions.create(SessionId('child'))
|
||||
|
||||
expect(() => sessions.fork({ source, sessionId: SessionId('child') }))
|
||||
expect(() => sessions.fork({ source, childSessionId: SessionId('child') }))
|
||||
.toThrow(new SessionForkError('session "child" already exists', 'SESSION_ALREADY_EXISTS'))
|
||||
})
|
||||
|
||||
it('rejects a duplicate child session id before validating the source boundary', async () => {
|
||||
it('rejects a duplicate child session id before validating the boundary', async () => {
|
||||
const { ctx, sessions } = await setup()
|
||||
const source = ctx.sessions.create(SessionId('open-parent'))
|
||||
source.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
|
||||
ctx.sessions.create(SessionId('child'))
|
||||
|
||||
expect(() => sessions.fork({ source, sessionId: SessionId('child') }))
|
||||
expect(() => sessions.fork({ source, childSessionId: SessionId('child') }))
|
||||
.toThrow(new SessionForkError('session "child" already exists', 'SESSION_ALREADY_EXISTS'))
|
||||
})
|
||||
})
|
||||
|
||||
Reference in New Issue
Block a user