fix pre-step lifecycle regressions

packages/context/time-context/src/invariant.ts

@@ -18,16 +18,20 @@ export const name = 'time-context-invariant'
 /** Service required before the companion can reserve package ownership. */
 export const inject = ['invariants']
 
-/** Derive the next request boundary at which a time-context reading may append. */
+/** Derive the entered step boundary at which a time-context reading may append. */
 function preparationPosition(history: readonly SessionEvent[], fail: InvariantFailure): { turn: number; step: number } {
   for (const event of history.slice().reverse()) {
     switch (event.type) {
-      case 'step/end':
-        return { turn: event.data.turn, step: event.data.step + 1 }
-      case 'turn/start':
-        return { turn: event.data.turn, step: 1 }
       case 'step/start':
+        return { turn: event.data.turn, step: event.data.step }
+      case 'turn/start':
+      case 'step/end':
       case 'turn/end':
+      case 'request/header':
+      case 'assistant/chunk':
+      case 'assistant/message':
+      case 'tool/call':
+      case 'tool/result':
         fail('time-context reading must be appended at a prompt boundary')
         break
       default:

packages/context/time-context/tests/invariant.spec.ts

@@ -58,6 +58,7 @@ function preparing(turn: number, step: number): Session {
     session.append('step/start', { turn, step: priorStep })
     session.append('step/end', { turn, step: priorStep })
   }
+  session.append('step/start', { turn, step })
   return session
 }
 
@@ -88,6 +89,7 @@ describe('time-context invariants', () => {
     await ctx.plugin(SessionStore)
     const session = ctx.sessions.create(SessionId('time-invariant-late-valid'))
     session.append('turn/start', { turn: 1 })
+    session.append('step/start', { turn: 1, step: 1 })
     session.append('user/message', createUserMessage({
       content: [{ type: 'text', text: 'prepare' }],
       source: { kind: 'user' },
@@ -103,6 +105,7 @@ describe('time-context invariants', () => {
     await ctx.plugin(SessionStore)
     const session = ctx.sessions.create(SessionId('time-invariant-late-invalid'))
     session.append('turn/start', { turn: 1 })
+    session.append('step/start', { turn: 1, step: 1 })
     session.append('user/message', createUserMessage({
       content: [{ type: 'text', text: 'prepare' }],
       source: { kind: 'user' },
@@ -132,7 +135,7 @@ describe('time-context invariants', () => {
   it('rejects a reading outside a prompt boundary', async () => {
     const ctx = await setup()
     const ended = preparing(1, 1)
-    ended.append('step/start', { turn: 1, step: 1 })
+    ended.append('step/end', { turn: 1, step: 1 })
     expect(() => { ctx.emit('session/event', ended, event(reading())) }).toThrow(/at a prompt boundary/)
     expect(() => {
       ctx.emit('session/event', new Session(SessionId('time-invariant-empty')), event(reading()))

packages/context/time-context/tests/time-context.spec.ts

@@ -17,7 +17,7 @@ const SIGNAL = new AbortController().signal
 
 beforeEach(() => {
   process.env['TZ'] = 'UTC'
-  vi.useFakeTimers()
+  vi.useFakeTimers({ toFake: ['Date'] })
   vi.setSystemTime(BASE)
 })
 
@@ -405,7 +405,7 @@ describe('real agent-loop request history', () => {
     expect(contexts).toHaveLength(adapter.requests.length)
     expect(starts).toHaveLength(adapter.requests.length)
     for (let index = 0; index < contexts.length; index += 1) {
-      expect(contexts[index]!.seq).toBeLessThan(starts[index]!.seq)
+      expect(contexts[index]!.seq).toBeGreaterThan(starts[index]!.seq)
     }
     expect(contexts.every(event => event.data.source.kind === 'plugin'
       && event.data.source.plugin === 'time-context'