mark packages installed here as 'auto' so they can be easily removed

This makes for clean autopkgtest runs.

Dockerfile

@@ -13,17 +13,20 @@ RUN mkdir -p /usr/share/man/man1 \
 	&& apt-get update \
 	&& apt-get -qy upgrade \
 	&& apt-get -qy dist-upgrade \
-	&& apt-get -qy install --no-install-recommends \
-		autodep8 \
-		autopkgtest \
+	&& export build_deps=' \
 		build-essential \
 		ca-certificates \
 		fakeroot \
 		git-buildpackage \
 		lintian \
-		pristine-tar \
+		pristine-tar' \
+	&& apt-get -qy install --no-install-recommends $build_deps \
+		autodep8 \
+		autopkgtest \
+		git \
 	&& apt-get -qy autoremove --purge \
 	&& apt-get clean \
+	&& apt-mark auto $build_deps \
 	&& rm -rf /var/lib/apt/lists/*
 
 COPY gitlab-ci-common /usr/share/

gitlab-ci-git-buildpackage

@@ -14,14 +14,13 @@ $apt_get update
 
 cd $CI_PROJECT_DIR
 if dpkg --compare-versions `dpkg -s apt |sed -n 's,^Version: \(.*\),\1,p'` ge 1.1; then
-    $apt_get build-dep $CI_PROJECT_DIR
+    $apt_get -o APT::Get::Build-Dep-Automatic=yes build-dep $CI_PROJECT_DIR
 else
     # this is running on an older version, like jessie-backports
     export BUILD_DEPENDS=`sed 's/\s*|[^,]*,/,/g' debian/control | perl -ne 'next if /^#/; $p=(s/^Build-Depends:\s*/ / or (/^ / and $p)); s/,|\n|\([^)]+\)//mg; print if $p'`
     $apt_get install --no-install-recommends \
              build-essential fakeroot git-buildpackage pristine-tar $BUILD_DEPENDS
 fi
-$apt_get autoremove --purge
 dpkg-checkbuilddeps
 echo "ensure pristine-tar branch exists and is current"
 git clean -fdx

gitlab-ci-git-buildpackage-all

@@ -24,6 +24,8 @@ cp ../*.deb $CI_PROJECT_DIR/
 
 gitlab-ci-lintian
 
+$apt_get autoremove --purge
+
 if [ -e $CI_PROJECT_DIR/debian/tests/control ]; then
     gitlab-ci-autopkgtest
 fi