fix(pty): feed the runtime once for in-process panes behind a degraded daemon (#33119)

When the daemon's PTY spawn check fails, the DegradedDaemonPtyProvider
routes fresh terminals to the in-process LocalPtyProvider. bindProviderListeners
decided whether to feed the runtime via `instanceof LocalPtyProvider` on the
registered provider, so behind the degraded wrapper every in-process chunk and
exit was ingested twice (once through configure().onData/onExit, once here),
doubling output sequence numbers and exit handling.

Tag each data/exit event with `runtimeFed` when the emitting provider already
reported it through configure(), and gate the listener's runtime feed on that
per-event flag instead of the provider's class.

Co-authored-by: Neil <4138956+nwparker@users.noreply.github.com>

src/main/ipc/pty-degraded-fallback-single-ingest.test.ts

@@ -0,0 +1,136 @@
+import { describe, expect, it, vi } from 'vitest'
+import { spawnMock } from './pty-ipc-mock-registry'
+import { setupPtyIpcSuite } from './pty-ipc-test-harness'
+import { registerPtyHandlers } from './pty/register-handlers'
+import { getLocalPtyProvider, setLocalPtyProvider } from './pty/provider/registry'
+import { rebindLocalProviderListeners } from './pty/provider/listener-lifecycle'
+import { DegradedDaemonPtyProvider } from '../daemon/degraded-daemon-pty-provider'
+import type { DaemonPtyAdapter } from '../daemon/daemon-pty-adapter'
+import type { PtyDataEvent } from '../providers/pty-provider-events'
+import { OrcaRuntimeService } from '../runtime/orca-runtime'
+
+vi.mock('electron', () => import('./pty-ipc-mock-registry').then((m) => m.electronModuleMock()))
+vi.mock('fs', () => import('./pty-ipc-mock-registry').then((m) => m.fsModuleMock()))
+vi.mock('node-pty', () => import('./pty-ipc-mock-registry').then((m) => m.nodePtyModuleMock()))
+vi.mock('node:child_process', async (importOriginal) =>
+  (await import('./pty-ipc-mock-registry')).childProcessModuleMock(await importOriginal())
+)
+vi.mock('../opencode/hook-service', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.openCodeHookServiceModuleMock())
+)
+vi.mock('../mimo/hook-service', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.mimoHookServiceModuleMock())
+)
+vi.mock('../agent-hooks/server', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.agentHookServerModuleMock())
+)
+vi.mock('../pi/titlebar-extension-service', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.piTitlebarExtensionModuleMock())
+)
+vi.mock('../pwsh', () => import('./pty-ipc-mock-registry').then((m) => m.pwshModuleMock()))
+vi.mock('../wsl', async (importOriginal) =>
+  (await import('./pty-ipc-mock-registry')).wslModuleMock(await importOriginal())
+)
+vi.mock('../telemetry/client', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.telemetryClientModuleMock())
+)
+vi.mock('../telemetry/classify-error', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.classifyErrorModuleMock())
+)
+vi.mock('../cli/linux-terminal-orca-cli-shim', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.linuxCliShimModuleMock())
+)
+vi.mock('../memory/pty-registry', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.ptyRegistryModuleMock())
+)
+vi.mock('../agent-hooks/migration-unsupported-pty-state', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.migrationUnsupportedPtyModuleMock())
+)
+vi.mock('../codex/codex-pane-account-registry', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.codexPaneAccountRegistryModuleMock())
+)
+vi.mock('../codex/codex-state-db-backfill-recovery', () =>
+  import('./pty-ipc-mock-registry').then((m) => m.codexBackfillRecoveryModuleMock())
+)
+
+// A daemon whose PTY spawn check failed: fresh terminals go to the in-process fallback.
+function createUnhealthyDaemonAdapter(daemonData: ((payload: PtyDataEvent) => void)[]) {
+  return {
+    spawn: vi.fn(async () => {
+      throw new Error('fresh spawns must not reach the unhealthy daemon')
+    }),
+    listProcesses: vi.fn(async () => []),
+    onData: vi.fn((cb: (payload: PtyDataEvent) => void) => {
+      daemonData.push(cb)
+      return () => {}
+    }),
+    onReplay: vi.fn(() => () => {}),
+    onExit: vi.fn(() => () => {}),
+    onWriteUnavailable: vi.fn(() => () => {})
+  }
+}
+
+describe('degraded daemon with in-process fallback', () => {
+  const { handlers, mainWindow, createMockProc } = setupPtyIpcSuite()
+
+  it('feeds each fallback PTY chunk and exit to the runtime once', async () => {
+    vi.useFakeTimers()
+    const mockProc = createMockProc()
+    spawnMock.mockReturnValue(mockProc.proc)
+    const runtime = new OrcaRuntimeService()
+    const onPtyData = vi.spyOn(runtime, 'onPtyData')
+    const onPtyExit = vi.spyOn(runtime, 'onPtyExit')
+    const daemonData: ((payload: PtyDataEvent) => void)[] = []
+    try {
+      handlers.clear()
+      // The window registers first, so the in-process provider is configured to feed the runtime.
+      registerPtyHandlers(mainWindow, runtime)
+      setLocalPtyProvider(
+        new DegradedDaemonPtyProvider({
+          // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: the degraded provider reaches only these adapter members on this spawn/data/exit path.
+          current: createUnhealthyDaemonAdapter(daemonData) as unknown as DaemonPtyAdapter,
+          legacy: [],
+          fallback: getLocalPtyProvider()
+        })
+      )
+      rebindLocalProviderListeners()
+
+      const spawned: unknown = await handlers.get('pty:spawn')!(null, {
+        cols: 80,
+        rows: 24,
+        cwd: '/tmp'
+      })
+      if (
+        !spawned ||
+        typeof spawned !== 'object' ||
+        !('id' in spawned) ||
+        typeof spawned.id !== 'string'
+      ) {
+        throw new Error('pty:spawn returned no id')
+      }
+      const { id } = spawned
+      mockProc.emitData('frame')
+      daemonData.forEach((cb) => cb({ id: 'daemon-pty', data: 'daemon' }))
+      await vi.advanceTimersByTimeAsync(50)
+
+      expect(onPtyData.mock.calls).toEqual([
+        [id, 'frame', expect.any(Number), 5, undefined],
+        ['daemon-pty', 'daemon', expect.any(Number), 6, undefined]
+      ])
+      expect(runtime.getPtyOutputSequence(id)).toBe(5)
+      expect(runtime.getPtyOutputSequence('daemon-pty')).toBe(6)
+      expect(mainWindow.webContents.send).toHaveBeenCalledWith('pty:data', {
+        id,
+        data: 'frame',
+        seq: 5,
+        rawLength: 5
+      })
+
+      mockProc.emitExit(0)
+      await vi.advanceTimersByTimeAsync(50)
+      expect(onPtyExit).toHaveBeenCalledTimes(1)
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+})

src/main/ipc/pty/provider/bind-listeners.ts

@@ -1,4 +1,3 @@
-import { LocalPtyProvider } from '../../../providers/local-pty-provider'
 import { isCurrentPtyExit, ptyOwnership } from './ownership-state'
 import {
   localBackgroundStreamUnsub,
@@ -66,13 +65,11 @@ export function bindProviderListeners(session: PtyIpcSession): void {
     }) ?? null
   )
 
-  // Daemon providers lack configure().onData; feed runtime records/streams here.
-  const isLocalProvider = localProvider instanceof LocalPtyProvider
-
+  // Feed the runtime unless the emitting provider already did via configure().
   setLocalDataUnsub(
     localProvider.onData((payload) => {
       const rawLength = payload.sequenceChars ?? payload.data.length
-      const outputSeq = isLocalProvider
+      const outputSeq = payload.runtimeFed
         ? session.runtime?.getPtyOutputSequence(payload.id)
         : session.runtime?.onPtyData(
             payload.id,
@@ -99,7 +96,7 @@ export function bindProviderListeners(session: PtyIpcSession): void {
           )
         : undefined
       try {
-        if (!isLocalProvider) {
+        if (!payload.runtimeFed) {
           const viewShown = ORCA_LAYOUT_OWNER_IS_MAIN && visibleRendererPtys.has(payload.id)
           clearProviderPtyState(payload.id)
           ptyOwnership.delete(payload.id)

src/main/providers/local-pty-provider-io-events.test.ts

@@ -248,15 +248,23 @@ describe('LocalPtyProvider', () => {
         ['prompt', expect.any(Number)]
       ])
       expect(dataHandler.mock.calls.map(([payload]) => payload)).toEqual([
-        { id, data: '', sequenceChars: query.length, seq: query.length, transformed: true },
+        {
+          id,
+          data: '',
+          sequenceChars: query.length,
+          seq: query.length,
+          transformed: true,
+          runtimeFed: true
+        },
         {
           id,
           data: '',
           sequenceChars: echo.length,
           seq: query.length + echo.length,
-          transformed: true
+          transformed: true,
+          runtimeFed: true
         },
-        { id, data: 'prompt' }
+        { id, data: 'prompt', runtimeFed: true }
       ])
     })
 

src/main/providers/local-pty-provider-state.ts

@@ -1,7 +1,8 @@
 import type * as pty from 'node-pty'
 import type { PhysicalExitTracker } from '../../shared/physical-exit-tracker'
 import type { PtyStartupIngress } from '../../shared/pty-startup-ingress'
-import type { TerminalExitCause } from '../../shared/terminal-exit-cause'
+import type { IPtyProvider } from './pty-provider-contract'
+import type { PtyDataEvent } from './pty-provider-events'
 import { getSpawnedShellName, normalizeLocalCallerSessionId } from './local-pty-launch-helpers'
 
 export type PtyShutdownOperation = {
@@ -15,20 +16,9 @@ export type PendingLocalPtySpawn = {
   cancellation: AbortController
 }
 
-export type DataCallback = (payload: {
-  id: string
-  data: string
-  sequenceChars?: number
-  transformed?: boolean
-  seq?: number
-}) => void
+export type DataCallback = (payload: PtyDataEvent) => void
 
-export type ExitCallback = (payload: {
-  id: string
-  code: number
-  incarnationId?: string
-  cause?: TerminalExitCause
-}) => void
+export type ExitCallback = Parameters<IPtyProvider['onExit']>[0]
 
 let ptyCounter = 0
 export const ptyProcesses = new Map<string, pty.IPty>()

src/main/providers/local-pty-session-activation.ts

@@ -81,11 +81,13 @@ export function activateLocalPtySession(args: {
 
   const emitIngressData = (emission: PtyIngressEmission): void => {
     const sequenceChars = emission.rawEndSeq - emission.rawStartSeq
+    const { onData } = getOptions()
     if (emission.transformed || sequenceChars !== emission.data.length) {
-      getOptions().onData?.(id, emission.data, Date.now(), sequenceChars, true)
+      onData?.(id, emission.data, Date.now(), sequenceChars, true)
     } else {
-      getOptions().onData?.(id, emission.data, Date.now())
+      onData?.(id, emission.data, Date.now())
     }
+    const runtimeFed = onData ? true : undefined
     for (const cb of dataListeners) {
       cb(
         emission.transformed || sequenceChars !== emission.data.length
@@ -94,9 +96,10 @@ export function activateLocalPtySession(args: {
               data: emission.data,
               sequenceChars,
               seq: emission.rawEndSeq,
-              transformed: true
+              transformed: true,
+              runtimeFed
             }
-          : { id, data: emission.data }
+          : { id, data: emission.data, runtimeFed }
       )
     }
   }
@@ -153,9 +156,10 @@ export function activateLocalPtySession(args: {
     // Release the natural-exit ptmx fd now instead of waiting for GC (docs/fix-pty-fd-leak.md).
     destroyPtyProcess(proc, { alreadyKilled: wasTerminationRequested })
     ptyReportsChildExitStatus.delete(id)
-    getOptions().onExit?.(id, exitCode, incarnationId, cause)
+    const { onExit } = getOptions()
+    onExit?.(id, exitCode, incarnationId, cause)
     for (const cb of exitListeners) {
-      cb({ id, code: exitCode, incarnationId, cause })
+      cb({ id, code: exitCode, incarnationId, cause, runtimeFed: onExit ? true : undefined })
     }
   })
   if (onExitDisposable) {

src/main/providers/pty-provider-contract.ts

@@ -221,6 +221,8 @@ export type IPtyProvider = {
       cause?: TerminalExitCause
       /** Main ended the session to restart the daemon; the pane stays for its next process. */
       replacedByRestart?: true
+      /** The emitting provider already reported this exit to the runtime through configure().onExit. */
+      runtimeFed?: true
     }) => void
   ): () => void
 }

src/main/providers/pty-provider-events.ts

@@ -6,6 +6,8 @@ export type PtyDataEvent = {
   sequenceChars?: number
   transformed?: boolean
   seq?: number
+  /** The emitting provider already fed this chunk to the runtime through configure().onData. */
+  runtimeFed?: true
 }
 
 /** Notification fact observed while the thinning transport owned scan authority for this PTY. */