Replace "stretch" with "buster" for Ruby 2.7-rc given the imminent Debian release

(and ditch Alpine 3.9 in 2.7-rc)

Author: tianon

.travis.yml

@@ -2,10 +2,9 @@ language: bash
 services: docker
 
 env:
-  - VERSION=2.7-rc VARIANT=stretch
-  - VERSION=2.7-rc VARIANT=stretch/slim
+  - VERSION=2.7-rc VARIANT=buster
+  - VERSION=2.7-rc VARIANT=buster/slim
   - VERSION=2.7-rc VARIANT=alpine3.10
-  - VERSION=2.7-rc VARIANT=alpine3.9
   - VERSION=2.6 VARIANT=stretch
   - VERSION=2.6 VARIANT=stretch/slim
   - VERSION=2.6 VARIANT=alpine3.10

2.7-rc/alpine3.9/Dockerfile

@@ -1,4 +1,4 @@
-FROM buildpack-deps:stretch
+FROM buildpack-deps:buster
 
 # skip installing gem documentation
 RUN mkdir -p /usr/local/etc \

2.7-rc/stretch/Dockerfile renamed to 2.7-rc/buster/Dockerfile

@@ -1,4 +1,4 @@
-FROM debian:stretch-slim
+FROM debian:buster-slim
 
 RUN apt-get update \
 	&& apt-get install -y --no-install-recommends \

2.7-rc/stretch/slim/Dockerfile renamed to 2.7-rc/buster/slim/Dockerfile

@@ -6,7 +6,10 @@ declare -A aliases=(
 	[2.7-rc]='rc'
 )
 
-defaultDebianSuite='stretch'
+defaultDebianSuite='stretch' # TODO buster
+declare -A debianSuites=(
+	[2.7-rc]='buster'
+)
 defaultAlpineVersion='3.10'
 declare -A alpineVersion=(
 	#[2.3]='3.8'
@@ -76,7 +79,7 @@ join() {
 
 for version in "${versions[@]}"; do
 	for v in \
-		{stretch,jessie}{,/slim} \
+		{buster,stretch,jessie}{,/slim} \
 		alpine{3.10,3.9} \
 	; do
 		dir="$version/$v"
@@ -101,12 +104,13 @@ for version in "${versions[@]}"; do
 		)
 
 		variantAliases=( "${versionAliases[@]/%/-$variant}" )
+		debianSuite="${debianSuites[$version]:-$defaultDebianSuite}"
 		case "$variant" in
-			"$defaultDebianSuite")
+			"$debianSuite")
 				variantAliases+=( "${versionAliases[@]}" )
 				;;
-			*-"$defaultDebianSuite")
-				variantAliases+=( "${versionAliases[@]/%/-${variant%-$defaultDebianSuite}}" )
+			*-"$debianSuite")
+				variantAliases+=( "${versionAliases[@]/%/-${variant%-$debianSuite}}" )
 				;;
 			"alpine${alpineVersion[$version]:-$defaultAlpineVersion}")
 				variantAliases+=( "${versionAliases[@]/%/-alpine}" )

generate-stackbrew-library.sh

@@ -72,7 +72,7 @@ for version in "${versions[@]}"; do
 
 	for v in \
 		alpine{3.9,3.10} \
-		{jessie,stretch}{/slim,} \
+		{jessie,stretch,buster}{/slim,} \
 	; do
 		dir="$version/$v"
 		variant="$(basename "$v")"