Add Yarn support

.circleci/config.yml

@@ -19,6 +19,8 @@ image_config: &image_config
 
   NODE_VERSION_NUM: # pick a version from https://nodejs.org/dist
 
+  YARN: # Yarn options: true, false
+
   PYTHON_VERSION_NUM: # pick a version from https://python.org/ftp/python
 
   JAVA: # Java options: true, false

scripts/generate.sh

@@ -26,6 +26,13 @@ if [ ! -e $NODE_VERSION_NUM ] ; then
     rm -r node-v$NODE_VERSION_NUM"
 fi
 
+if [ $YARN = "true" ] ; then
+    echo "RUN curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -"
+    echo "RUN echo \"deb https://dl.yarnpkg.com/debian/ stable main\" | tee /etc/apt/sources.list.d/yarn.list"
+    echo "RUN apt-get -y install apt-transport-https "
+    echo "RUN apt-get update && apt-get -y install yarn"
+fi
+
 if [ ! -e $PYTHON_VERSION_NUM ] ; then
     echo "RUN wget https://www.python.org/ftp/python/$PYTHON_VERSION_NUM/Python-$PYTHON_VERSION_NUM.tgz && \
     tar xzf Python-$PYTHON_VERSION_NUM.tgz && \

scripts/setup.sh

@@ -59,6 +59,20 @@ else
   perl -i -pe "s/- run: node/# - run: node/" .circleci/config.yml
 fi
 
+read -r -p "
+Does your project need Yarn? Enter the word 'yes' to install Yarn or hit enter to skip installing Yarn
+: " YARN
+
+case "$YARN" in
+  yes)
+    perl -i -pe 's/# Yarn options: true, false/true/' .circleci/config.yml
+    ;;
+  *)
+    perl -i -pe 's/# Yarn options: true, false/false/' .circleci/config.yml
+    perl -i -pe "s/- run: yarn/# - run: yarn/" .circleci/config.yml
+    ;;
+esac
+
 read -r -p "
 Pick a Python version from https://python.org/ftp/python, or hit enter to skip installing Python
 : " PYTHON_VERSION_NUM

scripts/tests.bats

@@ -12,6 +12,14 @@
   node --version | grep $NODE_VERSION_NUM
 }
 
+@test "yarn" {
+  if [ $YARN != "true" ] ; then
+    skip "yarn not installed"
+  fi
+
+  yarn --version
+}
+
 @test "ruby version" {
   if [ -e $RUBY_VERSION_NUM ] ; then
     skip "ruby not installed"