fix(pty): retain send ownership through cancellation

packages/pty/pty-local/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/pty/pty-local/README.md
-README.md: 74dfd7f59d45649f6daf0b42408285d9ede830a7
-README.zh.md: 2c7780f7e7db896c959e017dc39299e0e16f187d
+README.md: 7e31adfbc486a190252be867e2113948b17e7924
+README.zh.md: eb628aef9ad6b0fea14a5e833197b4fac7856785

packages/pty/pty-local/README.md

@@ -10,7 +10,7 @@ The plugin injects `pty`, `sandbox`, `sandboxPolicy`, and `subprocess`, then reg
 
 Readiness combines a foreground-verified private bash prompt marker, provider-reported foreground stdin-wait facts, silence fallback, and absolute timeout. A marker is not ready until the printable tail after the latest owned marker exactly equals the controlled `PS1`, including when the OSC marker and prompt are split across data callbacks; echoed input or output following a delayed earlier prompt therefore cannot settle the current send. Prompt and silence evidence collected before the provider write, including while pre-write foreground inspection is pending, is discarded at the write boundary. When bash prints the marker before the terminal provider publishes its return to the foreground process group, polling retains the candidate for `handoffGraceMs` past the ordinary silence bound so a coincident handoff can win. An interactive child that inherits `PROMPT_COMMAND` therefore cannot suppress inferred-idle readiness until the absolute timeout. Unknown foreground state is never a positive exact-idle signal. A foreground group's stdin wait that existed before a send is likewise not post-write readiness: the same group must be observed outside that wait before a later wait can settle the send, while a changed foreground group is new evidence. During unpublished startup, a fallback requires observed output; zero-output silence cannot publish an empty session, and timeout rejects the spawn. Cancellation closes the unpublished shell and rejects with the caller's exact abort reason; `PtyBackendCleanupError` separately preserves a cleanup failure. The terminal-allocation signal is detached when allocation returns, while readiness initialization keeps the setup signal, so later cancellation cannot terminate a published persistent session. Incomplete terminal-control sequences are bounded by `maxReadBytes` and discarded through their terminator after crossing that limit; a trailing carriage return is carried across callbacks so split CRLF becomes one newline.
 
-Send cancellation marks queued input as canceled before asking the terminal handle to signal the current foreground process group with a real `SIGINT`; if asynchronous pre-write inspection later settles, it cannot execute that input. Cancellation never emulates interruption by writing `\x03`, so raw-mode programs remain cancellable. A send that times out during an asynchronous provider write, or whose cancellation signal fails while that write remains pending, reports its result but retains the session's send slot until the write settles, so late bytes cannot interleave with a successor. Close starts provider-owned TERM-to-KILL whole-session cleanup and awaits quiescence after the terminal outcome. A cleanup failure does not cache a permanently rejected close; a later close retries the provider operation.
+Send cancellation marks queued input as canceled before asking the terminal handle to signal the current foreground process group with a real `SIGINT`; if asynchronous pre-write inspection later settles, it cannot execute that input. The canceled send retains its slot until foreground signalling settles, so a successor cannot become that signal's target. Cancellation never emulates interruption by writing `\x03`, so raw-mode programs remain cancellable. A send that times out during an asynchronous provider write, or whose cancellation signal fails while that write remains pending, reports its result but retains the slot until the write settles, so late bytes cannot interleave with a successor. Close starts provider-owned TERM-to-KILL whole-session cleanup and awaits quiescence after the terminal outcome. A cleanup failure does not cache a permanently rejected close; a later close retries the provider operation.
 
 ## Model Experience
 

packages/pty/pty-local/README.zh.md

@@ -10,7 +10,7 @@
 
 就绪检测结合以下机制：由前台状态验证的私有 bash 提示符标记、提供方报告的前台 stdin 等待事实、静默回退和绝对超时。只有最近一个自有标记之后的可打印尾部与受控 `PS1` 完全相等时，系统才会把标记视为就绪；即使 OSC 标记和提示符被拆到多个数据回调中也是如此。因此，如果回显的输入或输出跟在延迟到达的先前提示符之后，该提示符无法使当前 send 完成。系统会在写入边界丢弃提供方写入前收集的提示符与静默证据，包括写入前的前台检查尚未完成时收集的证据。如果 bash 在终端提供方发布其重新取得前台进程组的状态前打印标记，轮询会在普通静默上限之后再保留该候选状态 `handoffGraceMs`，使恰好同时发生的前台交接有机会胜出。因此，继承 `PROMPT_COMMAND` 的交互式子进程无法持续压制推断空闲就绪，最多只能延续到绝对超时。未知的前台状态绝不会作为精确空闲的正向信号。同样，一次 send 之前就已存在的前台进程组 stdin 等待并不代表写入后就绪：必须先观察到同一进程组脱离该等待，之后再次进入等待才能使该次 send 完成；前台进程组发生变化则构成新的证据。尚未发布的启动过程中，回退路径要求已经观察到输出；零输出静默不能发布空会话，超时则拒绝 spawn。取消操作会关闭尚未发布的 shell，并以调用方提供的确切中止原因拒绝；`PtyBackendCleanupError` 会单独保留清理失败。终端分配返回时，分配信号会解除关联；就绪初始化则保留设置阶段信号，因此后续取消无法终止已发布的持久会话。未完成的终端控制序列受 `maxReadBytes` 限制；超过上限后，系统会丢弃内容直到其终止符。末尾的回车会跨回调保留，使拆分的 CRLF 合并为一个换行。
 
-取消发送会先把排队输入标记为已取消，再请求终端句柄向当前前台进程组发送真正的 `SIGINT`；如果异步的写入前检查随后才结算，也无法执行该输入。取消绝不会通过写入 `\x03` 模拟中断，因此原始模式程序仍可取消。发送在提供方异步写入期间超时，或在该写入仍未完成时其取消信号发送失败，都会报告各自结果，但继续占用会话的发送槽位，直至写入结算，从而避免延迟到达的字节与后续发送交错。关闭操作启动由提供方负责的 TERM→KILL 全会话清理，并在终端结果之后等待完全停稳。清理失败不会缓存成永久拒绝的关闭操作；后续关闭会重试提供方操作。
+取消发送会先把排队输入标记为已取消，再请求终端句柄向当前前台进程组发送真正的 `SIGINT`；如果异步的写入前检查随后才结算，也无法执行该输入。被取消的发送会保留其槽位，直至前台信号发送结算，因此后续发送不会成为该信号的目标。取消绝不会通过写入 `\x03` 模拟中断，因此原始模式程序仍可取消。发送在提供方异步写入期间超时，或在该写入仍未完成时其取消信号发送失败，都会报告各自结果，但继续占用该槽位，直至写入结算，从而避免延迟到达的字节与后续发送交错。关闭操作启动由提供方负责的 TERM→KILL 全会话清理，并在终端结果之后等待完全停稳。清理失败不会缓存成永久拒绝的关闭操作；后续关闭会重试提供方操作。
 
 ## 模型体验
 

packages/pty/pty-local/src/session.ts

@@ -166,6 +166,7 @@ export class LocalPtySession implements PtyBackendSession {
   private activeDeadlineTimer: NodeJS.Timeout | undefined
   private activeAbort: (() => void) | undefined
   private readonly terminalOperations = new Set<Promise<void>>()
+  private interrupting: LocalSendOperation | undefined
   private writing: LocalSendOperation | undefined
   private pollingReady: LocalSendOperation | undefined
   private polling = false
@@ -403,7 +404,7 @@ export class LocalPtySession implements PtyBackendSession {
   }
 
   private schedulePoll(operation: LocalSendOperation, delayMs = this.config.pollIntervalMs): void {
-    if (this.active !== operation || this.polling) return
+    if (this.active !== operation || this.interrupting === operation || this.polling) return
     if (this.activeTimer !== undefined) clearTimeout(this.activeTimer)
     this.activeTimer = setTimeout(() => {
       this.activeTimer = undefined
@@ -480,9 +481,11 @@ export class LocalPtySession implements PtyBackendSession {
   }
 
   private clearActive(): void {
+    const operation = this.active
     this.stopPolling()
     this.activeAbort?.()
     this.activeAbort = undefined
+    if (this.interrupting === operation) this.interrupting = undefined
     this.writing = undefined
     this.pollingReady = undefined
     this.active = undefined
@@ -503,9 +506,24 @@ export class LocalPtySession implements PtyBackendSession {
 
   private interrupt(operation: LocalSendOperation): void {
     if (this.active !== operation) return
-    this.ownTerminalOperation(this.terminal.signalForeground('SIGINT').then(() => {}, (error: unknown) => {
+    this.interrupting = operation
+    this.stopPolling()
+    this.ownTerminalOperation(this.interruptOnce(operation))
+  }
+
+  private async interruptOnce(operation: LocalSendOperation): Promise<void> {
+    try {
+      await this.terminal.signalForeground('SIGINT')
+    } catch (error: unknown) {
       if (this.active === operation) this.failActive(error, this.writing === operation)
-    }))
+      return
+    } finally {
+      if (this.interrupting === operation) this.interrupting = undefined
+    }
+    if (this.active === operation && !operation.settled && !this.closing && this.writing !== operation) {
+      this.pollingReady = operation
+      this.schedulePoll(operation, 0)
+    }
   }
 
   private async closeOnce(reason: string): Promise<void> {

packages/pty/pty-local/tests/session.spec.ts

@@ -340,6 +340,60 @@ describe('LocalPtySession readiness and output', () => {
     await operation.done
   })
 
+  it('retains a canceled send until asynchronous foreground signalling settles', async () => {
+    vi.useFakeTimers()
+    const terminal = new FakeTerminal()
+    const inspector = new FakeInspector()
+    const session = makeSession(terminal, inspector, config())
+    await initialize(session, terminal)
+
+    const signalGate = Promise.withResolvers<undefined>()
+    terminal.signalForeground = async (signal) => {
+      await signalGate.promise
+      const foreground = await terminal.inspectForeground()
+      if (foreground === undefined) throw new Error('cannot resolve foreground')
+      inspector.signalGroup(foreground.processGroupId, signal)
+      return foreground.processGroupId
+    }
+    const operation = session.startSend({ text: 'first', submit: true })
+    await Promise.resolve()
+    await Promise.resolve()
+    expect(operation.cancel()).toBe(true)
+
+    terminal.emitData('\x1b]133;D;130\x07dsh> ')
+    await vi.advanceTimersByTimeAsync(10)
+    expect(() => session.startSend({ text: 'successor', submit: true })).toThrow('active send')
+    signalGate.resolve(undefined)
+    await vi.advanceTimersByTimeAsync(10)
+    await operation.done
+    expect(inspector.groups).toContainEqual([456, 'SIGINT'])
+    expect(inspector.groups).not.toContainEqual([789, 'SIGINT'])
+  })
+
+  it('does not resume cancellation polling after the terminal exits during signalling', async () => {
+    vi.useFakeTimers()
+    const terminal = new FakeTerminal()
+    const inspector = new FakeInspector()
+    const session = makeSession(terminal, inspector, config())
+    await initialize(session, terminal)
+
+    const signalGate = Promise.withResolvers<undefined>()
+    terminal.signalForeground = async () => {
+      await signalGate.promise
+      return 456
+    }
+    const operation = session.startSend({ text: 'first', submit: true })
+    await Promise.resolve()
+    await Promise.resolve()
+    expect(operation.cancel()).toBe(true)
+    terminal.emitExit(0)
+    await expect(operation.done).resolves.toMatchObject({ waitReason: 'session_exit' })
+
+    signalGate.resolve(undefined)
+    await vi.advanceTimersByTimeAsync(10)
+    expect(session.status()).toEqual({ kind: 'exited', exitCode: 0, signal: null })
+  })
+
   it('retains send ownership after timeout until an asynchronous provider write settles', async () => {
     vi.useFakeTimers()
     const terminal = new FakeTerminal()