From 1b014cd5e2bb38702f897f073221a6f23a007738 Mon Sep 17 00:00:00 2001
From: Chris Graf <chris@grafhome.net>
Date: Tue, 3 Nov 2026 08:37:38 -0600
Subject: [PATCH] Bypass `env` in the closed-stdin `autolint` test

Summary
The scheduled `Tests` run failed `files0 stdin: closed descriptor` on
the Ubuntu and WSL legs once `ubuntu-latest` moved to Ubuntu 26.04.
The product guard was never at fault: the test closed fd 0 and then
ran `bin/autolint` through its `#!/usr/bin/env bash` shebang, and
Ubuntu 26.04's `env` comes from uutils coreutils. Rust's std runtime
reopens any closed descriptor 0-2 on /dev/null before `main`, so
autolint received an open, empty /dev/null stream, indistinguishable
from a deliberate `</dev/null` empty manifest.

- run the closed-stdin case as `"$BASH" "$AUTOLINT"`, so the closed
  descriptor reaches the guard on every platform
- leave `_autolint_read_files0` unchanged: its `/dev/stdin` probe is
  correct whenever fd 0 actually arrives closed
- supersedes the automated fix in #128, which blamed the probe and
  then bash

Testing
- reproduced locally with a minimal Rust exec wrapper standing in for
  uutils `env`: fd 0 arrives as /dev/null and `autolint --files0-from
  - <&-` exits 0 silently, while GNU `env` and direct `bash` keep fd 0
  closed and exit 2 with the actionable message
- #128's CI diagnostic showed fd 0 as `lrwx` /dev/null inside
  autolint, matching Rust's O_RDWR reopen rather than a shell redirect
- removing the guard makes the updated invocation exit 0, so the test
  still catches a regression
- `test/suites/autolint-test`: 517 passed, 0 failed
- `test/checkrun-test`: only `schema-refresh` refs cases fail, from
  the local host lacking the `referencing` library; that suite is
  untouched
- `checkrun format`, `checkrun lint`, and the shellcheck-inventory
  check at the locked cgraf78/actions SHA pass
---
 test/suites/autolint-test | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/test/suites/autolint-test b/test/suites/autolint-test
index d434a1a..85feee4 100755
--- a/test/suites/autolint-test
+++ b/test/suites/autolint-test
@@ -3055,8 +3055,12 @@ set -e
 _assert_exit "files0 stdin: empty input is a no-op" 0 "$rc"
 _assert_eq "files0 stdin: empty input is quiet" "" "$output"
 
+# Run the script with this suite's Bash rather than through its
+# `#!/usr/bin/env bash` shebang: Ubuntu 26.04's `env` is uutils, and Rust's
+# std runtime reopens closed descriptors 0-2 on /dev/null before `main`, so
+# the guard would only ever see an empty stream there.
 set +e
-output=$("$AUTOLINT" --files0-from - <&- 2>&1)
+output=$("$BASH" "$AUTOLINT" --files0-from - <&- 2>&1)
 rc=$?
 set -e
 _assert_exit "files0 stdin: closed descriptor exits 2" 2 "$rc"