feat(acp): the bridge approval answerer + scripted permission answers

The ACP bridge registers the first real approval answerer: an ask for an agent it owns becomes session/request_permission attached to the already- streamed tool call (one-shot allow_once/reject_once only), outcomes map conservatively (unknown optionId never grants, client cancel → cancelled), and foreign or call-less requests delegate down the waterfall. The snapshot harness accepts scripted permissionAnswers (FIFO; an unscripted prompt answers cancelled, fail closed) so recorded scenarios can drive the wire keylessly.
2026-07-09 15:36:08 +08:00
parent ef35007d75
commit 80d8726601
18 changed files with 302 additions and 30 deletions
--- a/packages/support/acp-snapshot/README.md
+++ b/packages/support/acp-snapshot/README.md
@@ -35,4 +35,4 @@ A scenario booting a differently-composed tree sets its own `configPath` (an ove

 The example also ships a `cordis.snapshot.yml` replay overlay next to its `cordis.yml` (the bin swaps them under `DSH_SNAPSHOT=replay` — [single-source replay config RFC](../../../docs/rfc/implemented/testing/2026-07-04-single-source-acp-replay-config.md)); replay fixtures are served by [`dsh-llm-replay`](../llm-replay/README.md), which this package points at via the `DSH_SNAPSHOT_*` env vars it sets on the child. Fixture roles, record/replay semantics, and scenario-table fields are documented on `Scenario` and in the [snapshot RFC](../../../docs/rfc/implemented/testing/2026-06-19-acp-snapshot-tests.md).

-Constraints: `suite.ts` imports vitest, so the package is importable only inside a vitest run (the harness and normalizers have no such dependency but ship from the same entry). ACP-specific by design — the harness speaks the SDK's `ClientSideConnection`. Permission round-trips are scriptable: `InputScript.permissionAnswers` is a FIFO queue of option-kind selections (`allow_once`, `reject_once`, …) the client maps to the agent-issued `optionId` at answer time; an absent or exhausted queue answers `cancelled`, and a kind the request never offered rejects the run (the agent is answered `cancelled`, so a tolerant agent cannot absorb the scenario bug).
+Constraints: `suite.ts` imports vitest, so the package is importable only inside a vitest run (the harness and normalizers have no such dependency but ship from the same entry). ACP-specific by design — the harness speaks the SDK's `ClientSideConnection`. Permission round-trips are scriptable: `InputScript.permissionAnswers` is a FIFO queue of option-kind selections (`allow_once`, `reject_once`, …) the client maps to the agent-issued `optionId` at answer time; an absent or exhausted queue answers `cancelled`, and a kind the request never offered rejects the run (the agent is answered `cancelled`, so a tolerant agent cannot absorb the scenario bug). Session config options are scriptable too: the `setConfigOption` step switches a knob over `session/set_config_option`, and `setConfigOptionExpectError` asserts the bridge rejects an unknown id or out-of-vocabulary value (the error frame stays in the transcript).
--- a/packages/support/acp-snapshot/src/harness.ts
+++ b/packages/support/acp-snapshot/src/harness.ts
@@ -85,6 +85,8 @@ export type InputStep =
  | { op: 'promptExpectError'; text: string }
  | { op: 'promptAndCancel'; text: string }
  | { op: 'cancel' }
+  | { op: 'setConfigOption'; configId: string; value: string }
+  | { op: 'setConfigOptionExpectError'; configId: string; value: string }

 /** A scenario's `input.json`: an ordered list of input steps. */
 export interface InputScript {
@@ -406,6 +408,24 @@ async function runStep(
      await client.cancel({ sessionId })
      return
    }
+    case 'setConfigOption': {
+      const sessionId = getSessionId()
+      if (sessionId === undefined) throw new Error('snapshot-harness: setConfigOption before newSession')
+      await client.setSessionConfigOption({ sessionId, configId: step.configId, value: step.value })
+      return
+    }
+    case 'setConfigOptionExpectError': {
+      const sessionId = getSessionId()
+      if (sessionId === undefined) throw new Error('snapshot-harness: setConfigOptionExpectError before newSession')
+      // The bridge rejects an unknown id / out-of-vocabulary value; the SDK
+      // surfaces that as a rejected RPC — swallow it so the run completes and
+      // the error frame is captured in the transcript.
+      await client.setSessionConfigOption({ sessionId, configId: step.configId, value: step.value }).then(
+        () => { throw new Error('snapshot-harness: expected set_config_option to be rejected but it succeeded') },
+        () => { /* expected: the bridge rejected the id or value */ },
+      )
+      return
+    }
    default:
      throw new Error(`snapshot-harness: unknown input op ${JSON.stringify(step)}`)
  }
--- a/packages/support/acp-snapshot/tests/fixtures/fake-acp-agent.ts
+++ b/packages/support/acp-snapshot/tests/fixtures/fake-acp-agent.ts
@@ -58,6 +58,13 @@ interface Behavior {
  strayBucketFile?: boolean
  /** Delete the sessions root entirely (harvest must yield no logs). */
  deleteSessionsRoot?: boolean
+  /**
+   * Vocabulary for `session/set_config_option`: allowed values per config id.
+   * A set naming an unknown id or an out-of-vocabulary value rejects (the
+   * real bridge's rule); a valid set answers with the complete refreshed
+   * option state, `currentValue` updated. Absent: every set rejects.
+   */
+  configOptions?: Record<string, string[]>
 }

 const sessionsRoot = process.env.DSH_SNAPSHOT_SESSIONS_ROOT ?? ''
@@ -81,6 +88,8 @@ let sessionCwd = ''
 let parkedPromptId: number | string | null = null
 /** Resolvers for permission-probe responses, keyed by outbound request id. */
 const pendingPermission = new Map<number, (outcome: unknown) => void>()
+/** Per-run `session/set_config_option` state: config id → current value (first vocabulary entry until set). */
+const currentConfig: Record<string, string> = {}

 function send(frame: Record<string, unknown>): void {
  process.stdout.write(`${JSON.stringify({ jsonrpc: '2.0', ...frame })}\n`)
@@ -195,6 +204,32 @@ function handleFrame(frame: Record<string, unknown>): void {
    case 'session/prompt':
      void handlePrompt(id as number | string)
      return
+    case 'session/set_config_option': {
+      const vocabulary = behavior.configOptions
+      const configId = params.configId as string
+      const value = params.value as string
+      const values = vocabulary?.[configId]
+      if (values === undefined) {
+        respondError(id as number | string, `unknown config option ${configId}`)
+        return
+      }
+      if (!values.includes(value)) {
+        respondError(id as number | string, `unknown ${configId} value ${value}`)
+        return
+      }
+      currentConfig[configId] = value
+      // The real bridge's contract: every set answers with the COMPLETE
+      // refreshed option state, not just the changed entry.
+      respond(id as number | string, {
+        configOptions: Object.entries(vocabulary as Record<string, string[]>).map(([cid, vs]) => ({
+          id: cid,
+          type: 'select',
+          currentValue: currentConfig[cid] ?? vs[0],
+          options: vs.map(v => ({ value: v, name: v })),
+        })),
+      })
+      return
+    }
    case 'session/cancel':
      if (parkedPromptId !== null) {
        const parked = parkedPromptId
--- a/packages/support/acp-snapshot/tests/harness.spec.ts
+++ b/packages/support/acp-snapshot/tests/harness.spec.ts
@@ -168,6 +168,8 @@ describe('runScenario', () => {
    [{ op: 'promptExpectError', text: 'x' }, /promptExpectError before newSession/],
    [{ op: 'promptAndCancel', text: 'x' }, /promptAndCancel before newSession/],
    [{ op: 'cancel' }, /cancel before newSession/],
+    [{ op: 'setConfigOption', configId: 'sandbox-mode', value: 'read-only' }, /setConfigOption before newSession/],
+    [{ op: 'setConfigOptionExpectError', configId: 'sandbox-mode', value: 'yolo' }, /setConfigOptionExpectError before newSession/],
  ] as [InputStep, RegExp][])('rejects %j before newSession', { timeout: 20_000 }, async (step, message) => {
    const { fixtureFile } = await scenario({})
    await expect(runScenario(
@@ -176,6 +178,53 @@ describe('runScenario', () => {
    )).rejects.toThrow(message)
  })

+  it('setConfigOption switches a value and receives the complete refreshed option state', { timeout: 20_000 }, async () => {
+    const { fixtureFile } = await scenario({
+      configOptions: { 'sandbox-mode': ['read-only', 'workspace-write'], 'approval-policy': ['ask', 'never'] },
+    })
+    const result = await runScenario(
+      {
+        steps: [...boot,
+          { op: 'setConfigOption', configId: 'sandbox-mode', value: 'workspace-write' },
+          { op: 'setConfigOption', configId: 'approval-policy', value: 'never' }],
+      },
+      { agent: AGENT, mode: 'replay', fixtureFile },
+    )
+    // Every set answers with the FULL state: the second response carries the
+    // first switch's value too — the complete-refreshed-state contract.
+    const frames = result.rawStdout.trim().split('\n').map(line => JSON.parse(line) as { result?: { configOptions?: { id: string; currentValue: string }[] } })
+    const states = frames
+      .map(f => f.result?.configOptions)
+      .filter(options => options !== undefined)
+      .map(options => Object.fromEntries((options as { id: string; currentValue: string }[]).map(o => [o.id, o.currentValue])))
+    expect(states).toEqual([
+      { 'sandbox-mode': 'workspace-write', 'approval-policy': 'ask' },
+      { 'sandbox-mode': 'workspace-write', 'approval-policy': 'never' },
+    ])
+  })
+
+  it('setConfigOptionExpectError swallows the rejection for unknown ids and out-of-vocabulary values', { timeout: 20_000 }, async () => {
+    const { fixtureFile } = await scenario({ configOptions: { 'sandbox-mode': ['read-only'] } })
+    const result = await runScenario(
+      {
+        steps: [...boot,
+          { op: 'setConfigOptionExpectError', configId: 'sandbox-mode', value: 'yolo' },
+          { op: 'setConfigOptionExpectError', configId: 'reasoning-effort', value: 'max' }],
+      },
+      { agent: AGENT, mode: 'replay', fixtureFile },
+    )
+    expect(result.rawStdout).toContain('unknown sandbox-mode value yolo')
+    expect(result.rawStdout).toContain('unknown config option reasoning-effort')
+  })
+
+  it('setConfigOptionExpectError throws when the set unexpectedly succeeds', { timeout: 20_000 }, async () => {
+    const { fixtureFile } = await scenario({ configOptions: { 'sandbox-mode': ['read-only'] } })
+    await expect(runScenario(
+      { steps: [...boot, { op: 'setConfigOptionExpectError', configId: 'sandbox-mode', value: 'read-only' }] },
+      { agent: AGENT, mode: 'replay', fixtureFile },
+    )).rejects.toThrow(/expected set_config_option to be rejected/)
+  })
+
  it('rejects an unknown input op', { timeout: 20_000 }, async () => {
    const { fixtureFile } = await scenario({})
    const bogus = { op: 'reticulate' } as unknown as InputStep