Use jq's IN() instead of index()

The end result is the same, but the construction is more ergonomic.

Dockerfile.template

@@ -59,7 +59,7 @@ ENV HAPROXY_SHA256 {{ .sha256 }}
 		# Since 5.4 is supported on haproxy, better use it now, but only for
 		# newer versions since there could be some minor incompatibilities
 		# for existing scripts: https://www.lua.org/manual/5.4/manual.html#8
-		if ([ "2.2", "2.4", "2.6", "2.8" ] | index(env.version)) then
+		if env.version | IN("2.2", "2.4", "2.6", "2.8") then
 			"5.3"
 		else
 			"5.4"
@@ -81,7 +81,7 @@ RUN set -eux; \
 		pcre2-dev \
 		readline-dev \
 		tar \
-{{ if ([ "2.2" ] | index(env.version)) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 		zlib-dev \
 {{ ) else "" end -}}
 	; \
@@ -95,7 +95,7 @@ RUN set -eux; \
 		libssl-dev \
 		make \
 		wget \
-{{ if ([ "2.2" ] | index(env.version)) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 		zlib1g-dev \
 {{ ) else "" end -}}
 	; \
@@ -122,15 +122,15 @@ RUN set -eux; \
 		USE_LUA=1 LUA_INC=/usr/include/lua{{ lua }}{{ if env.variant == "alpine" then (" LUA_LIB=/usr/lib/lua" + lua) else "" end }} \
 		USE_OPENSSL=1 \
 		USE_PCRE2=1 USE_PCRE2_JIT=1 \
-{{ if ([ "2.2" ] | index(env.version)) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 		USE_ZLIB=1 \
 {{ ) else "" end -}}
-{{ if ([ "2.2" ] | index(env.version) | not) then ( -}}
+{{ if env.version == "2.2" then "" else ( -}}
 		USE_PROMEX=1 \
-{{ ) else "" end -}}
+{{ ) end -}}
 		\
 		EXTRA_OBJS=" \
-{{ if [ "2.2" ] | index(env.version) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 # see https://github.com/docker-library/haproxy/issues/94#issuecomment-505673353 for more details about prometheus support
 			contrib/prometheus-exporter/service-prometheus.o \
 {{ ) else "" end -}}
@@ -188,12 +188,12 @@ RUN set -eux; \
 STOPSIGNAL SIGUSR1
 
 COPY docker-entrypoint.sh /usr/local/bin/
-{{ if [ "2.2" ] | index(env.version) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 RUN ln -s usr/local/bin/docker-entrypoint.sh / # backwards compat
 {{ ) else "" end -}}
 ENTRYPOINT ["docker-entrypoint.sh"]
 
-{{ if [ "2.2" ] | index(env.version) then ( -}}
+{{ if env.version == "2.2" then ( -}}
 # no USER for backwards compatibility (to try to avoid breaking existing users)
 {{ ) else ( -}}
 USER haproxy

versions.sh

@@ -37,7 +37,7 @@ for version in "${versions[@]}"; do
 				alpine: env.alpine,
 			}
 			# remove Alpine from versions where it cannot be built on any active Alpine release
-			| if [ "2.2" ] | index(env.version) then del(.alpine) else . end
+			| if env.version == "2.2" then del(.alpine) else . end
 		'
 	)"