refactor(token-meter): merge measurement snapshots (round 1)

packages/compact/compact-basic/src/index.ts

@@ -123,13 +123,7 @@ export class BasicCompactService extends CompactService {
 
     let result: CompactionResult | null = null
     for (let attempt = 0; attempt <= this.config.compactionRetries; attempt += 1) {
-      const surface = meter.measureSurface(agent.session)
-      if (surface.logRevision !== measurement.logRevision) {
-        throw new Error(
-          `compaction: pressure revision ${measurement.logRevision} does not match surface revision ${surface.logRevision}`,
-        )
-      }
-      const range = selectCompactableRange(agent.session, surface, this.config.retainTokens)
+      const range = selectCompactableRange(agent.session, measurement, this.config.retainTokens)
       if (range === null) {
         /* v8 ignore else -- concrete replacement preserves a compactable checkpoint; subclass hooks cannot mutate it. */
         if (result === null) return null

packages/compact/compact-basic/src/region.ts

@@ -10,7 +10,7 @@ import {
   toolPairingBalancedBefore,
 } from '@deepseek-ai/dsh-compact'
 import type { CompactionResult } from '@deepseek-ai/dsh-compact'
-import type { TokenMeterService, TokenSurfaceMeasurement } from '@deepseek-ai/dsh-token-meter'
+import type { TokenMeasurement, TokenMeterService } from '@deepseek-ai/dsh-token-meter'
 import type { Session, SessionEvent } from '@deepseek-ai/dsh-session'
 import type { Agent } from '@deepseek-ai/dsh-agent'
 import { frameSummary } from './summarizer.ts'
@@ -25,16 +25,16 @@ interface RegionDependencies {
  * Resolve the next head-anchored range while retaining a priced recent tail
  * and never splitting an assistant tool-call/result pair.
  * @param session - session supplying authoritative current surface positions.
- * @param pricedSurface - same-revision surface measurement from the conversation meter.
+ * @param measurement - unified pressure and surface measurement from the conversation meter.
  * @param retainTokens - minimum recent tail budget retained verbatim.
  * @returns the inclusive positional seq range to compact, or `null`.
  */
 export function selectCompactableRange(
   session: Session,
-  pricedSurface: TokenSurfaceMeasurement,
+  measurement: TokenMeasurement,
   retainTokens: number,
 ): { start: number; end: number } | null {
-  const pricedNodes = pricedSurface.nodes
+  const pricedNodes = measurement.nodes
   if (pricedNodes.length === 0) return null
 
   const surfaceNodes = session.surface.nodes
@@ -115,8 +115,8 @@ export async function compactSurfaceRegion(
   try {
     // Capture after the lock event so any later durable append, including a
     // log-only one, invalidates the async selection before replacement.
-    const lockedSurface = dependencies.meter.measureSurface(session)
-    const selected = lockedSurface.nodes.slice(startIdx, endIdx + 1)
+    const lockedMeasurement = dependencies.meter.measure(session)
+    const selected = lockedMeasurement.nodes.slice(startIdx, endIdx + 1)
     if (selected.length !== shadowedSeqs.length
       || selected.some((node, index) => node.seq !== shadowedSeqs[index])) {
       throw new Error('compaction: selected surface changed before summarization began')
@@ -125,8 +125,8 @@ export async function compactSurfaceRegion(
     const text = renderTranscript(session.events, shadowedSeqs)
     const { summary, model, maxTokens } = await dependencies.summarize(text, agent, signal)
 
-    const currentSurface = dependencies.meter.measureSurface(session)
-    if (currentSurface.logRevision !== lockedSurface.logRevision) {
+    const currentMeasurement = dependencies.meter.measure(session)
+    if (currentMeasurement.logRevision !== lockedMeasurement.logRevision) {
       throw new Error('compaction: session log changed during summarization')
     }
     const framedSummary = frameSummary(summary)

packages/compact/compact-basic/tests/compact-basic.spec.ts

@@ -251,17 +251,15 @@ describe('pressure measurement and retention', () => {
     expect(await compactIfNeeded(compact, retained, MODEL, 'x'.repeat(100_000))).toBeNull()
   })
 
-  it('detects scalar/surface revision disagreement', async () => {
+  it('uses one unified measurement for each pressure-and-retention decision', async () => {
     const ctx = createContext()
-    const meter = ctx.tokenMeter
-    const original = meter.measureSurface.bind(meter)
-    vi.spyOn(meter, 'measureSurface').mockImplementation((session) => {
-      const measurement = original(session)
-      return { ...measurement, logRevision: measurement.logRevision - 1 }
-    })
     const compact = service(compactConfig, ctx)
+    const measure = vi.spyOn(ctx.tokenMeter, 'measure')
+    const stop = new Error('stop after first decision')
+    vi.spyOn(compact, 'compactRegion').mockRejectedValueOnce(stop)
 
-    await expect(compactIfNeeded(compact, conversation(4))).rejects.toThrow(/revision/)
+    await expect(compactIfNeeded(compact, conversation(4))).rejects.toBe(stop)
+    expect(measure).toHaveBeenCalledTimes(1)
   })
 
   it('bounds retries when a shrinking checkpoint remains above threshold', async () => {
@@ -303,7 +301,7 @@ describe('pressure measurement and retention', () => {
   it('rejects a priced surface that is not the current positional surface', () => {
     const ctx = createContext()
     const session = conversation(2)
-    const priced = ctx.tokenMeter.measureSurface(session)
+    const priced = ctx.tokenMeter.measure(session)
     expect(() => selectCompactableRange(session, {
       ...priced,
       nodes: priced.nodes.slice(1),
@@ -331,7 +329,7 @@ describe('pressure measurement and retention', () => {
     }, { surfaceOp: 'append' })
     session.append('step/end', { turn: 1, step: 1 })
 
-    const priced = ctx.tokenMeter.measureSurface(session)
+    const priced = ctx.tokenMeter.measure(session)
     expect(selectCompactableRange(session, priced, 1)).toBeNull()
   })
 })
@@ -474,8 +472,8 @@ describe('compaction region transaction', () => {
   it('rejects a meter snapshot that changed before summarization began', async () => {
     const ctx = createContext()
     const meter = ctx.tokenMeter
-    const original = meter.measureSurface.bind(meter)
-    vi.spyOn(meter, 'measureSurface').mockImplementationOnce((session) => {
+    const original = meter.measure.bind(meter)
+    vi.spyOn(meter, 'measure').mockImplementationOnce((session) => {
       const measurement = original(session)
       return { ...measurement, nodes: measurement.nodes.slice(1) }
     })