Drop the Windows PowerShell picker fallback
删除 Windows PowerShell 选择器回退
The win32 branch of the native directory picker kept a two-tier PowerShell fallback under the koffi `IFileOpenDialog` child process: `pwsh.exe` first, then `powershell.exe` (Windows PowerShell 5.1), both running the same WinForms script with a `SetProcessDPIAware` opt-in. The chain existed to keep a working chooser when the koffi tier was "unavailable", but every trigger it plausibly protected was a failure of our ow
English
Problem
The win32 branch of the native directory picker kept a two-tier PowerShell fallback under the koffi IFileOpenDialog child process: pwsh.exe first, then powershell.exe (Windows PowerShell 5.1), both running the same WinForms script with a SetProcessDPIAware opt-in. The chain existed to keep a working chooser when the koffi tier was "unavailable", but every trigger it plausibly protected was a failure of our own packaging or deployment, not of the operating system:
- koffi's native binary ships as an ordinary optional dependency (
@koromix/koffi-win32-x64, no install script); a host that installs the package at all has the binary, and a host that cannot install it fails the package install loudly — the fallback code never loads either. - "Ancient Windows" cannot occur: the Node versions this repo supports run on Windows generations far newer than the Vista-era
IFileOpenDialogABI the dialog needs. - A koffi/COM defect crashes only the dialog child process (crash isolation); the correct response to our own bug is a surfaced failure, not a silent downgrade to a legacy dialog.
The chain also cost real complexity: two spawn tiers running one identical script, a fallback trigger widened from ENOENT to any pwsh failure to close the PowerShell 6 (no WinForms) regression, a triple-miss AggregateError carrying all three causes, and per-tier abort re-checks. The seam already owns the only fallback that matters — the browse backend at the composition level, chosen once at boot by directory-picker-auto.
Decision
The win32 tier is exactly the koffi IFileOpenDialog child process; any failure surfaces as-is with no fallback. The PowerShell chain — the pwsh → Windows PowerShell 5.1 cascade, the DPI-corrected WinForms script, the AggregateError aggregation — is deleted, and pickNativeDirectory's win32 branch is a single call. dsh-native-command remains a dependency for the POSIX tiers.
The fallback criterion the rest of the package already followed now applies uniformly: a fallback tier exists only for tools the OS/desktop environment provides and may omit (zenity → kdialog on Linux, which the boot-time probe also samples); tools our own package ships (koffi) fail loud. macOS osascript stays fallback-free as before.
This change consolidates and deletes the pwsh-first DPI picker-fix note: its decision is fully reversed here, and its preserved rationale no longer guides future work on a koffi-only tier. What it kept that was real: PowerShell 7 renders the modern IFileDialog-based folder picker where 5.1's FolderBrowserDialog is hardwired to the legacy SHBrowseForFolder tree; the script's SetProcessDPIAware corrected the spawn's system-DPI ceiling; the pwsh→5.1 hop existed because a resolvable PowerShell 6 has no WinForms (exit 1, not ENOENT). Its rejected alternatives (requiring PowerShell 7, importing resolvePwshPath, setting DPI awareness in the harness process) are moot with the chain gone.
Alternatives considered
Keep the chain but drop the pwsh quality tier (koffi → Windows PowerShell 5.1). Rejected: the remaining tier still defends our own packaged dependency, still costs the script, the widened trigger, and the aggregation, and still hides our own vtable/COM defects behind a legacy dialog. The criterion "fallback only for externally provided tools" admits no Windows tier at all.
Keep the chain as-is. Rejected: it was the only two-level runtime fallback in the picker surface, its triggers were deployment-side failures that fail loud anyway, and it degraded a failed pick into an AggregateError whose most actionable entry was a PowerShell host.
Fall back to browse at runtime when the native pick fails. Rejected: the seam's flow holes are single-kind and the -auto composition already picks one backend at boot; a runtime cross-kind hop would double-mount both backends and blur the capability boundary.
Consequences
- The win32 picker's failure surface is one error from one tier; callers see the real cause (koffi load failure, COM refusal, dialog crash) instead of a chain-aggregated error.
pwsh/powershell.exeare no longer invoked by this package; the WinForms script, itsSetProcessDPIAwarecorrection, and the-STAflags are gone with them.- Tests shrink accordingly: the pwsh/5.1 cascade and triple-miss cases are replaced by one "failure surfaces with no fallback" case; the default-adapter test now drives the Linux tier.
- Reintroduction condition: a future win32 mechanism outside our packaging chain (a system-provided dialog host we do not ship) would justify a single fallback tier under the same criterion.
中文
问题
原生目录选择器的 win32 分支在 koffi IFileOpenDialog 子进程之下保留了一条两级 PowerShell 回退：先 pwsh.exe，再 powershell.exe（Windows PowerShell 5.1），两者运行同一个主动启用 SetProcessDPIAware 的 WinForms 脚本。该链的存在是为了在 koffi 层「不可用」时仍能给出一个可用的选择器，但它可能保护的每一个触发条件都是我们自己打包或部署的失败，而不是操作系统的：
- koffi 的原生二进制作为普通的可选 NPM 依赖（
@koromix/koffi-win32-x64，无 install script）分发；能装上该包的宿主就一定有二进制，装不上的宿主会在安装期明确报错——回退代码也根本不会得到加载。 - 「上古 Windows」不可能出现：本仓库支持的 Node 版本运行在远比 Vista 时代
IFileOpenDialogABI 新的 Windows 世代上。 - koffi/COM 缺陷只崩对话框子进程（crash isolation）；对我们自己 bug 的正确反应是上报失败，而不是静默降级到旧版对话框。
这条链还付出了真实的复杂度：两个 spawn 层运行同一脚本、把回退触发从 ENOENT 拓宽为 pwsh 的任何失败以修复 PowerShell 6（无 WinForms）回归问题、携带全部三个原因的三连败 AggregateError，以及每层的 abort 重检。seam 早已拥有唯一重要的回退——组合层面的 browse 后端，由 directory-picker-auto 在启动时选择一次。
决策
win32 层恰好就是 koffi IFileOpenDialog 子进程；任何失败原样上报，无回退。PowerShell 链——pwsh → Windows PowerShell 5.1 级联、DPI 修正的 WinForms 脚本、AggregateError 聚合——被删除，pickNativeDirectory 的 win32 分支成为单次调用。dsh-native-command 仍为 POSIX 层保留依赖。
本包其余部分早已遵循的回退判据现在统一适用：回退层只存在于操作系统/桌面环境提供且可能缺失的工具（Linux 的 zenity → kdialog，启动探针同样采样它们）；我们自己打包的工具（koffi）失败即明确报错。macOS osascript 与之前一样保持无回退。
本次变更合并并删除了 pwsh 优先的 DPI 选择器修复 Agent Note：其决策在此被完全反转，其保留的理由对只含 koffi 的层不再指导未来工作。其中真实的部分：PowerShell 7 呈现基于 IFileDialog 的现代文件夹选择器，而 5.1 的 FolderBrowserDialog 被硬连到旧版 SHBrowseForFolder 树；脚本的 SetProcessDPIAware 修正了 spawn 的系统 DPI 上限；pwsh→5.1 的跳转存在是因为可解析的 PowerShell 6 没有 WinForms（退出码 1，而非 ENOENT）。其被拒绝的替代方案（要求 PowerShell 7、导入 resolvePwshPath、在 harness 进程设置 DPI 感知）随链删除而失去意义。
考虑过的替代方案
**保留链但去掉 pwsh 质量层（koffi → Windows PowerShell 5.1）。**拒绝：剩下的层仍在防范我们自己打包的依赖发生故障，仍要付出脚本、拓宽的触发与聚合的代价，仍会把我们自己的 vtable/COM 缺陷藏到旧版对话框后面。「仅对外部提供的工具回退」的判据不接受任何 Windows 层。
**原样保留链。**拒绝：它是选择器中唯一的二级运行时回退，其触发条件是本就会明确报错的部署侧失败，并且它把一次失败的选择操作降级为 AggregateError，其中最具可操作性的条目却指向 PowerShell 宿主。
**原生 pick 失败时在运行时回退到 browse。**拒绝：seam 的流程洞属于 single 类型，-auto 组合已在启动时选择一个后端；运行时跨类型跳转会同时挂载两个后端并模糊能力边界。
后果
- win32 选择器的失败面是来自单一层的一个错误；调用方看到真实原因（koffi 加载失败、COM 拒绝、对话框崩溃），而不是链式聚合的错误。
- 本包不再调用
pwsh/powershell.exe；WinForms 脚本、其SetProcessDPIAware修正与-STA标志随之消失。 - 测试相应缩减：pwsh/5.1 级联与三连败用例被一个「失败原样上报、无回退」用例取代；默认适配器测试改驱动 Linux 层。
- 重新引入条件：未来出现在我们打包链之外的 win32 机制（我们不随包分发的系统提供的对话框宿主）才值得在同一判据下保留一层回退。