fix(pwsh): accept link-shaped candidates and sync the README contract

This commit is contained in:
Huanqi Cao
2026-08-12 15:11:20 +08:00
committed by Chinesezjc
parent 7593842ccf
commit 29d420f1ee
5 changed files with 28 additions and 11 deletions
+1 -1
View File
@@ -30,7 +30,7 @@ The Windows counterpart of `dsh-bash-local`, deliberately mirroring its semantic
- **Spawn per call, no shell state** — every call is a fresh non-interactive `pwsh -Command` (deterministic; no profile files). The `-NoLogo -NoProfile -NonInteractive` flags disable startup banners, profile loading, and prompts that would garble tool output.
- **The composition entry is a layer, not the last word** — when a settings provider is composed, this executor registers the capability's [`bash` namespace](../shell/README.md) with the entry above as its base, so a user section in `settings.yaml` layers over it and the next command runs with the new budgets. The namespace is shared with the POSIX family because a host composes exactly one provider of `ctx.shell`; a document written on either platform keeps resolving on the other. Values the schema cannot judge (positive and finite, the `graceMs` timer bound) are refused at the write, leaving the running executor on its last good section.
- **UTF-8 output pinned** — every command runs with `[Console]::OutputEncoding` and `$OutputEncoding` set to UTF-8 first, so the Windows PowerShell 5.1 fallback (or any host whose console code page is not UTF-8) cannot garble non-ASCII output: the subprocess collector decodes bytes as UTF-8. Input encoding is left at the host default; pwsh 7 defaults to UTF-8 and is unaffected.
- **Executable resolution** — `resolvePwshPath` prefers an explicit `pwshPath`, then on Windows probes PowerShell 7's install location, every PATH entry (Microsoft Store installs; surrounding quotes stripped), and Windows PowerShell 5.1 as a legacy last resort, checking `existsSync` on each; elsewhere it falls back to a bare `pwsh` resolved through PATH. Resolution is a pure function of `(configured, env, platform)`; it runs at construction and again only when a stored `pwshPath` differs from the one the current executable was resolved from, so an unrelated settings change never re-probes the filesystem.
- **Executable resolution** — `resolvePwshPath` prefers an explicit `pwshPath`, then on Windows probes PowerShell 7's install location, every PATH entry (Microsoft Store installs; surrounding quotes stripped), and Windows PowerShell 5.1 as a legacy last resort, checking each candidate with an lstat probe that accepts a real file or a link-shaped reparse point (a Store app execution alias stat-fails against its target's ACL, but lstat sees the alias itself); elsewhere it falls back to a bare `pwsh` resolved through PATH. Resolution is a pure function of `(configured, env, platform)`; it runs at construction and again only when a stored `pwshPath` differs from the one the current executable was resolved from, so an unrelated settings change never re-probes the filesystem.
- **Configured budgets over managed groups** — `resolve()` fills `workdir`/`timeoutMs`/`stdoutMaxBytes` from config, and every spawn hands the service explicit byte caps, spill cap, and `graceMs`. The grace must be positive, finite, and no greater than [`MAX_TIMER_DELAY_MS`](../../util/timeout/README.md), so Node can represent it with one timer. Tree termination (taskkill on Windows, process-group signals on POSIX), the post-exit pipe-drain grace, tail-keep truncation, and bounded spill files are [`dsh-subprocess-local`](../../subprocess/subprocess-local/README.md) mechanics. A foreground `ShellExecRequest.stdoutMaxBytes` can raise stdout's capture budget for one trusted caller; stderr and background runs still use `maxOutputBytes`.
- **Timeout and cancel classification** — `run()` fuses its config-clamped timeout with the caller's signal through one deadline; only the executor's own timeout reports `timedOut`, an upstream cancel reports `aborted`, and a self-terminated command reports neither ([timeout-library Agent Note](../../../.agents/notes/implemented/architecture/2026-07-06-timeout-deadline-library.md)). Windows reports forced termination as exit 1 without a signal, so signal-stamped facts (`signal`, `killed` status) are POSIX-only there; the timeout/abort classification is platform-independent.
- **Model-friendly terminal env** — `NO_COLOR=1 PAGER=cat GIT_PAGER=cat` (no `TERM=dumb`: that is a POSIX concept; `NO_COLOR` is honored by modern PowerShell renderers) merged as ordinary env under the service's credential scrub and `DSH_*` channel rules; an explicit caller entry still wins.