From d9bcad79b7de8f1491e6309cd06f7d966245603d Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Sat, 20 Jun 2026 16:37:01 +0200
Subject: [PATCH] pacman-helper: tolerate removing a package absent from a
 database

The `quick_remove` action recently started to fail when asked to drop a
package that no longer lives in every database it touches. Removing the
obsolete `git-credential-manager-core` packages aborted as soon as the
removal reached the freshly-initialized, still-empty `ucrt64` database,
with `repo-remove` reporting `Package matching '...' not found.` and
`quick_remove` turning that into a fatal error.

This only surfaced once we taught `quick_action` to run the removal
across the second and third databases (`mingw64` and `ucrt64`) in
addition to the architecture database. `repo-remove` is all-or-nothing:
if any requested name is absent it leaves the database untouched and
exits non-zero (in /usr/bin/repo-remove a failed `remove` sets `fail=1`,
after which it prints `Package database was not modified due to errors.`
and exits 1). A package that only ever lived in one of the databases
therefore makes the whole operation fail, even though removing a package
that is not there ought to be a harmless no-op.

Simply ignoring `repo-remove`'s exit code is not an option: besides
papering over genuine errors, the all-or-nothing behavior would also
silently skip packages that *are* present alongside an absent one.
Instead, I now filter the requested names against the database's actual
contents (via the existing `package_list` helper, stripping the
`-<pkgver>-<pkgrel>` suffix and matching whole names so that
`git-credential-manager` is not mistaken for
`git-credential-manager-core`) and only hand the survivors to
`repo-remove`, skipping the call entirely when nothing is left to
remove.

This is the run that motivated the change:
https://github.com/git-for-windows/git-for-windows-automation/actions/runs/27195671090

Assisted-by: Opus 4.8
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 pacman-helper.sh | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/pacman-helper.sh b/pacman-helper.sh
index 66829adf03..3905d7730a 100755
--- a/pacman-helper.sh
+++ b/pacman-helper.sh
@@ -131,15 +131,30 @@ repo_remove () {
 		# Make sure that GPGKEY is used unquoted
 		 sed 's/"\(\${\?GPGKEY}\?\)"/\1/g' </usr/bin/repo-remove >"$this_script_dir/repo-remove"
 	fi &&
-	"$this_script_dir/repo-remove" $(for arg
-	do
-		# repo-remove only accepts package _names_, but we are potentially given _files_.
-		# Handle this by distilling the package names from filenames.
-		case "$arg" in
-		*.pkg.tar.xz|*.pkg.tar.zst) echo "${arg%-*-*-*}";;
-		*) echo "$arg";;
-		esac
-	done)
+	# repo-remove only accepts package _names_, but we are potentially given
+	# _files_; distill the names from the file names. Furthermore, repo-remove
+	# fails the _entire_ operation (modifying nothing) when _any_ of the given
+	# names is absent from the database, e.g. a freshly-initialized, still-empty
+	# ucrt64 database. To allow removing a package even when it is not present in
+	# a given database, drop the names the database does not contain and skip the
+	# call altogether when nothing is left to remove.
+	dbfile="$1" &&
+	shift &&
+	present=" $(package_list "$dbfile" | sed 's/-[^-]*-[^-]*$//' | tr '\n' ' ')" &&
+	names= &&
+	{
+		for arg
+		do
+			case "$arg" in
+			*.pkg.tar.xz|*.pkg.tar.zst) name="${arg%-*-*-*}";;
+			*) name="$arg";;
+			esac
+			case "$present" in
+			*" $name "*) names="$names $name";;
+			esac
+		done
+	} &&
+	{ test -z "$names" || "$this_script_dir/repo-remove" "$dbfile" $names; }
 }
 
 update_versions_json () { # <file> <version> <tagname>