Enhance "generate-stackbrew-library.sh" to only take into account changes to the Dockerfile or files from COPY in the Dockerfile for choosing the commit hash for a particular directory

Author: tianon

generate-stackbrew-library.sh

@@ -16,7 +16,7 @@ url='git://github.com/docker-library/redis'
 echo '# maintainer: InfoSiftr <[email protected]> (@infosiftr)'
 
 for version in "${versions[@]}"; do
-	commit="$(git log -1 --format='format:%H' -- "$version")"
+	commit="$(cd "$version" && git log -1 --format='format:%H' -- Dockerfile $(awk 'toupper($1) == "COPY" { for (i = 2; i < NF; i++) { print $i } }' Dockerfile))"
 	fullVersion="$(grep -m1 'ENV REDIS_VERSION ' "$version/Dockerfile" | cut -d' ' -f3)"
 
 	versionAliases=()
@@ -33,7 +33,7 @@ for version in "${versions[@]}"; do
 
 	for variant in 32bit; do
 		[ -f "$version/$variant/Dockerfile" ] || continue
-		commit="$(git log -1 --format='format:%H' -- "$version/$variant")"
+		commit="$(cd "$version/$variant" && git log -1 --format='format:%H' -- Dockerfile $(awk 'toupper($1) == "COPY" { for (i = 2; i < NF; i++) { print $i } }' Dockerfile))"
 		echo
 		for va in "${versionAliases[@]}"; do
 			if [ "$va" = 'latest' ]; then