Merge pull request #153 from infosiftr/cleanup

Cleanup comments and remove unnecessary conditional

Dockerfile-scm.template

@@ -1,7 +1,8 @@
 FROM buildpack-deps:{{ env.codename }}-curl
 
-# procps is very common in build systems, and is a reasonably small package
-RUN apt-get update && apt-get install -y --no-install-recommends \
+RUN set -eux; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends \
 {{
 if [
 	"focal", "groovy"
@@ -14,5 +15,7 @@ if [
 		openssh-client \
 		subversion \
 		\
+# procps is very common in build systems, and is a reasonably small package
 		procps \
-	&& rm -rf /var/lib/apt/lists/*
+	; \
+	rm -rf /var/lib/apt/lists/*

Dockerfile.template

@@ -6,6 +6,7 @@ RUN set -ex; \
 		autoconf \
 		automake \
 		bzip2 \
+		default-libmysqlclient-dev \
 		dpkg-dev \
 		file \
 		g++ \
@@ -43,15 +44,5 @@ RUN set -ex; \
 		unzip \
 		xz-utils \
 		zlib1g-dev \
-		\
-# https://lists.debian.org/debian-devel-announce/2016/09/msg00000.html
-		$( \
-# if we use just "apt-cache show" here, it returns zero because "Can't select versions from package 'libmysqlclient-dev' as it is purely virtual", hence the pipe to grep
-			if apt-cache show 'default-libmysqlclient-dev' 2>/dev/null | grep -q '^Version:'; then \
-				echo 'default-libmysqlclient-dev'; \
-			else \
-				echo 'libmysqlclient-dev'; \
-			fi \
-		) \
 	; \
 	rm -rf /var/lib/apt/lists/*