Reduce Docker image layer by merging mkdir operation

test/Dockerfile-alpine

@@ -8,8 +8,7 @@ WORKDIR /root
 
 # Create nginx directories in standard places
 RUN mkdir /run/nginx
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 
 # BATS (Bash Automated Testings)
 RUN git clone --depth 1 https://github.com/bats-core/bats-core.git /bats-core --branch v1.2.1

test/Dockerfile-centos6

@@ -11,8 +11,7 @@ RUN yum -y install epel-release
 RUN yum -y install git curl dnsutils ldns wget nginx
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/conf.d/default.conf
 
 # BATS (Bash Automated Testings)

test/Dockerfile-centos7

@@ -6,8 +6,7 @@ RUN yum -y install epel-release
 RUN yum -y install git curl ldns bind-utils wget which nginx
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/conf.d/default.conf
 COPY ./test/test-config/nginx-centos7.conf /etc/nginx/nginx.conf
 

test/Dockerfile-centos7-staging

@@ -11,8 +11,7 @@ ENV staging "true"
 ENV DUCKDNS_TOKEN 1d616aa9-b8e4-4bb4-b312-3289de82badb
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/conf.d/default.conf
 COPY ./test/test-config/nginx-centos7.conf /etc/nginx/nginx.conf
 

test/Dockerfile-centos8

@@ -8,8 +8,7 @@ RUN yum -y install epel-release
 RUN yum -y install git curl bind-utils wget which nginx
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/conf.d/default.conf
 COPY ./test/test-config/nginx-centos7.conf /etc/nginx/nginx.conf
 

test/Dockerfile-debian

@@ -7,8 +7,7 @@ RUN apt-get update --fix-missing
 RUN apt-get install -y git curl dnsutils ldnsutils wget nginx-light
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 
 # BATS (Bash Automated Testings)
 RUN git clone --depth 1 https://github.com/bats-core/bats-core.git /bats-core --branch v1.2.1

test/Dockerfile-ubuntu16

@@ -8,8 +8,7 @@ RUN apt-get update --fix-missing
 RUN apt-get install -y git curl dnsutils ldnsutils wget nginx-light
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/sites-enabled/default
 
 # BATS (Bash Automated Testings)

test/Dockerfile-ubuntu18

@@ -8,8 +8,7 @@ RUN apt-get update --fix-missing
 RUN apt-get install -y git curl dnsutils ldnsutils wget gawk nginx-light
 
 WORKDIR /root
-RUN mkdir /etc/nginx/pki
-RUN mkdir /etc/nginx/pki/private
+RUN mkdir -p /etc/nginx/pki/private
 COPY ./test/test-config/nginx-ubuntu-no-ssl /etc/nginx/sites-enabled/default
 
 # Prevent "Can't load /root/.rnd into RNG" error from openssl