feat(yq): add fallback 3rd party completion loader

Author: scop

completions/Makefile.am

@@ -477,6 +477,7 @@ bashcomp_DATA = 2to3 \
 		xz \
 		xzdec \
 		ypmatch \
+		_yq \
 		_yum \
 		yum-arch \
 		zopfli \

completions/_yq

@@ -0,0 +1,18 @@
+# 3rd party completion loader for commands emitting        -*- shell-script -*-
+# their completion using "$cmd shell-completion bash".
+#
+# This serves as a fallback in case the completion is not installed otherwise.
+
+# shellcheck disable=SC2168 # "local" is ok, assume sourced by __load_completion
+local _comp__load_3rdparty_reset_shopt=$(shopt -po posix)
+set +o posix
+
+. <("$1" shell-completion bash 2>/dev/null)
+
+$_comp__load_3rdparty_reset_shopt
+
+{
+    complete -p "$1" || complete -p "${1##*/}"
+} &>/dev/null
+
+# ex: filetype=sh

test/fallback/completions/Makefile.am

@@ -34,4 +34,5 @@ EXTRA_DIST = \
 	umount.linux \
 	write \
 	xm \
+	yq \
 	yum

test/fallback/completions/yq

@@ -0,0 +1 @@
+../../../completions/_yq