Merge remote-tracking branch 'upstream/master'

.gitignore

 .anvil
 .DS_Store
+

.travis.yml

@@ -3,8 +3,13 @@ sudo: required
 services:
   - docker
 env:
-  - STACK=heroku-18
-  - STACK=heroku-16
-  - STACK=cedar-14
-install: docker pull "heroku/${STACK/-/:}"
-script: make test-${STACK}
+  - TEST=heroku-18 STACK=heroku-18
+  - TEST=heroku-16 STACK=heroku-16
+  - TEST=cedar-14 STACK=cedar-14
+  - TEST=hatchet
+  - TEST=unit
+install:
+  - if [[ -n $STACK ]]; then
+      docker pull "heroku/${STACK/-/:}";
+    fi
+script: make ${TEST}

CHANGELOG.md

 # Node.js Buildpack Changelog
 
-## Master
+## master
+
+## v126 (2018-09-06)
+
+- Icrease Node memory default during builds (#561)
+- Rework output when caching directories (#559)
+- Only write export script if directory is writeable (#539)
+- Testing changes (#552, #557, #558)
+- Upgrade the Node Metrics plugin (#564)
+
+## v125 (2018-08-24)
+
+- Fix issue with old Node and metrics plugin (#555)
+
+## v124 (2018-08-23)
+
+- Add plugin for [Node.js Language Metrics](https://devcenter.heroku.com/articles/language-runtime-metrics-nodejs)
+
+## v123 (2018-03-14)
+
+- Internal logging changes
+
+## v122 (2018-03-13)
+
+- Internal logging changes
 
 ## v121 (2018-03-02)
 

Gemfile

+source "https://rubygems.org"
+
+gem 'heroku_hatchet'
+gem 'rspec-retry'
+gem 'rspec-expectations'
+gem 'sem_version'
+gem "parallel_tests"
+gem "rake"

Gemfile.lock

+GEM
+  remote: https://rubygems.org/
+  specs:
+    activesupport (5.2.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+    concurrent-ruby (1.0.5)
+    diff-lcs (1.3)
+    erubis (2.7.0)
+    excon (0.62.0)
+    heroics (0.0.24)
+      erubis (~> 2.0)
+      excon
+      moneta
+      multi_json (>= 1.9.2)
+    heroku_hatchet (4.0.5)
+      excon (~> 0)
+      minitest-retry (~> 0.1.9)
+      platform-api (~> 2)
+      repl_runner (~> 0.0.3)
+      rrrretry (~> 1)
+      thor (~> 0)
+      threaded (~> 0)
+    i18n (1.1.0)
+      concurrent-ruby (~> 1.0)
+    minitest (5.11.3)
+    minitest-retry (0.1.9)
+      minitest (>= 5.0)
+    moneta (0.8.1)
+    multi_json (1.13.1)
+    parallel (1.12.1)
+    parallel_tests (2.22.0)
+      parallel
+    platform-api (2.1.0)
+      heroics (~> 0.0.23)
+      moneta (~> 0.8.1)
+    rake (12.3.1)
+    repl_runner (0.0.3)
+      activesupport
+    rrrretry (1.0.0)
+    rspec-core (3.8.0)
+      rspec-support (~> 3.8.0)
+    rspec-expectations (3.8.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.8.0)
+    rspec-retry (0.6.1)
+      rspec-core (> 3.3)
+    rspec-support (3.8.0)
+    sem_version (2.0.1)
+    thor (0.20.0)
+    thread_safe (0.3.6)
+    threaded (0.0.4)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  heroku_hatchet
+  parallel_tests
+  rake
+  rspec-expectations
+  rspec-retry
+  sem_version
+
+BUNDLED WITH
+   1.16.4

bin/compile

@@ -9,7 +9,6 @@ unset GIT_DIR     # Avoid GIT_DIR leak from previous build steps
 
 ### Constants
 
-DEFAULT_CACHE="node_modules bower_components"
 BPLOG_PREFIX="buildpack.nodejs"
 
 ### Configure directories
@@ -17,7 +16,7 @@ BPLOG_PREFIX="buildpack.nodejs"
 BUILD_DIR=${1:-}
 CACHE_DIR=${2:-}
 ENV_DIR=${3:-}
-BP_DIR=$(cd $(dirname ${0:-}); cd ..; pwd)
+BP_DIR=$(cd "$(dirname ${0:-})"; cd ..; pwd)
 STDLIB_FILE=$(mktemp -t stdlib.XXXXX)
 
 ### Load dependencies
@@ -25,12 +24,14 @@ STDLIB_FILE=$(mktemp -t stdlib.XXXXX)
 curl --silent --retry 5 --retry-max-time 15 'https://wj-backend.oss-cn-hongkong.aliyuncs.com/heroku/lang-common/buildpack-stdlib/v7/stdlib.sh' > "$STDLIB_FILE"
 source "$STDLIB_FILE"
 source $BP_DIR/lib/output.sh
+source $BP_DIR/lib/monitor.sh
 source $BP_DIR/lib/json.sh
 source $BP_DIR/lib/failure.sh
 source $BP_DIR/lib/environment.sh
 source $BP_DIR/lib/binaries.sh
 source $BP_DIR/lib/cache.sh
 source $BP_DIR/lib/dependencies.sh
+source $BP_DIR/lib/plugin.sh
 
 export PATH="$BUILD_DIR/.heroku/node/bin:$BUILD_DIR/.heroku/yarn/bin":$PATH
 
@@ -79,12 +80,13 @@ create_env() {
   create_default_env
 }
 
-header "Creating runtime environment"
+header "Creating runtime environment" | output "$LOG_FILE"
 
 mkdir -p "$BUILD_DIR/.heroku/node/"
 cd $BUILD_DIR
 create_env # can't pipe the whole thing because piping causes subshells, preventing exports
 list_node_config | output "$LOG_FILE"
+create_build_env
 
 ### Configure package manager cache directories
 [ ! "$YARN_CACHE_FOLDER" ] && export YARN_CACHE_FOLDER=$(mktemp -d -t yarncache.XXXXX)
@@ -110,13 +112,16 @@ install_bins() {
   if [ -n "$iojs_engine" ]; then
     warn_node_engine "$iojs_engine"
     install_iojs "$iojs_engine" "$BUILD_DIR/.heroku/node"
-    echo "Using bundled npm version for iojs compatibility: `npm --version`"
-    mcount "version.iojs.$(node --version)"
+    local npm_version="$(npm --version)"
+    local node_version="$(node --version)"
+    echo "Using bundled npm version for iojs compatibility: $npm_version"
+    mcount "version.iojs.$node_version"
   else
     warn_node_engine "$node_engine"
     install_nodejs "$node_engine" "$BUILD_DIR/.heroku/node"
     install_npm "$npm_engine" "$BUILD_DIR/.heroku/node" $NPM_LOCK
-    mcount "version.node.$(node --version)"
+    local node_version="$(node --version)"
+    mcount "version.node.$node_version"
   fi
 
   # Download yarn if there is a yarn.lock file or if the user
@@ -135,11 +140,12 @@ install_bins() {
   warn_old_npm
 }
 
-header "Installing binaries"
+header "Installing binaries" | output "$LOG_FILE"
 install_bins | output "$LOG_FILE"
 
 restore_cache() {
   local cache_status="$(get_cache_status)"
+  local cache_directories="$(get_cache_directories)"
 
   if $YARN; then
     if [ -e "$BUILD_DIR/node_modules" ]; then
@@ -147,23 +153,38 @@ restore_cache() {
       rm -rf "$BUILD_DIR/node_modules"
     fi
   fi
-  if [ "$cache_status" == "valid" ]; then
-    local cache_directories=$(get_cache_directories)
-    if [ "$cache_directories" == "" ]; then
-      echo "Loading 2 from cacheDirectories (default):"
-      restore_cache_directories "$BUILD_DIR" "$CACHE_DIR" "$DEFAULT_CACHE"
+
+  if [[ "$cache_status" == "disabled" ]]; then
+    header "Restoring cache"
+    echo "Caching has been disabled because NODE_MODULES_CACHE=${NODE_MODULES_CACHE}"
+  elif [[ "$cache_status" == "valid" ]]; then
+    header "Restoring cache"
+    if [[ "$cache_directories" == "" ]]; then
+      restore_default_cache_directories "$BUILD_DIR" "$CACHE_DIR"
+    else
+      restore_custom_cache_directories "$BUILD_DIR" "$CACHE_DIR" $cache_directories
+    fi
+  elif [[ "$cache_status" == "new-signature" ]]; then
+    header "Restoring cache"
+    if [[ "$cache_directories" == "" ]]; then
+      echo "Cached directories were not restored due to a change in version of node, npm, yarn or stack"
+      echo "Module installation may take longer for this build"
     else
-      echo "Loading $(echo $cache_directories | wc -w | xargs) from cacheDirectories (package.json):"
-      restore_cache_directories "$BUILD_DIR" "$CACHE_DIR" $cache_directories
+      # If the user has specified custom cache directories, be more explicit
+      echo "Invalidating cache due to a change in version of node, npm, yarn or stack"
+      echo "Will not restore the following directories for this build:"
+      for directory in $(< $cache_directories); do
+        echo "  $directory"
+      done
     fi
   else
-    echo "Skipping cache restore ($cache_status)"
+    # No cache exists, be silent
+    :
   fi
 
   mcount "cache.$cache_status"
 }
 
-header "Restoring cache"
 restore_cache | output "$LOG_FILE"
 
 build_dependencies() {
@@ -188,27 +209,27 @@ build_dependencies() {
   log_build_scripts
 }
 
-header "Building dependencies"
+header "Building dependencies" | output "$LOG_FILE"
 build_dependencies | output "$LOG_FILE"
 
 cache_build() {
-  local cache_directories=$(get_cache_directories)
+  local cache_directories="$(get_cache_directories)"
 
-  echo "Clearing previous node cache"
   clear_cache
   if ! ${NODE_MODULES_CACHE:-true}; then
-    echo "Skipping cache save (disabled by config)"
-  elif [ "$cache_directories" == "" ]; then
-    echo "Saving 2 cacheDirectories (default):"
-    save_cache_directories "$BUILD_DIR" "$CACHE_DIR" "$DEFAULT_CACHE"
+    # we've already warned that caching is disabled in the restore step
+    # so be silent here
+    :
+  elif [[ "$cache_directories" == "" ]]; then
+    header "Caching build"
+    save_default_cache_directories "$BUILD_DIR" "$CACHE_DIR"
   else
-    echo "Saving $(echo $cache_directories | wc -w | xargs) cacheDirectories (package.json):"
-    save_cache_directories "$BUILD_DIR" "$CACHE_DIR" $cache_directories
+    header "Caching build"
+    save_custom_cache_directories "$BUILD_DIR" "$CACHE_DIR" $cache_directories
   fi
   save_signature
 }
 
-header "Caching build"
 cache_build | output "$LOG_FILE"
 
 prune_devdependencies() {
@@ -219,7 +240,7 @@ prune_devdependencies() {
   fi
 }
 
-header "Pruning devDependencies"
+header "Pruning devDependencies" | output "$LOG_FILE"
 prune_devdependencies | output "$LOG_FILE"
 
 summarize_build() {
@@ -230,7 +251,9 @@ summarize_build() {
   mmeasure 'modules.size' "$(measure_size)"
 }
 
-header "Build succeeded!"
+install_plugin $BP_DIR $BUILD_DIR
+
+header "Build succeeded!" | output "$LOG_FILE"
 mcount "compile"
 summarize_build | output "$LOG_FILE"
 

bin/detect

 #!/usr/bin/env bash
 # bin/detect <build-dir>
 
+error() {
+  local c="2,999 s/^/ !     /"
+	# send all of our output to stderr
+	exec 1>&2
+
+	echo -e "\033[1;31m" # bold; red
+	echo -n " !     ERROR: "
+	# this will be fed from stdin
+  case $(uname) in
+		Darwin) sed -l "$c";; # mac/bsd sed: -l buffers on line boundaries
+		*)      sed -u "$c";; # unix/gnu sed: -u unbuffered (arbitrary) chunks of data
+	esac
+	echo -e "\033[0m" # reset style
+	exit 1
+}
+
 if [ -f $1/package.json ]; then
   echo 'Node.js'
   exit 0
 fi
 
->&2 echo 'Node.js: package.json not found in application root'
+if [[ -f "$1/.slugignore" ]] && grep -Fxq "package.json" "$1/.slugignore"; then
+  error << EOF
+'package.json' listed in '.slugignore' file
+
+The 'heroku/nodejs' buildpack is set on this application, but was
+unable to detect a 'package.json' file. This is likely because
+the '.slugignore' file is removing it before the build begins.
+
+For more information, refer to the following documentation:
+https://devcenter.heroku.com/articles/slug-compiler#ignoring-files-with-slugignore
+EOF
+elif [[ -f "$1/.gitignore" ]] && grep -Fxq "package.json" "$1/.gitignore"; then
+  error << EOF
+'package.json' listed in '.gitignore' file
+
+The 'heroku/nodejs' buildpack is set on this application, but was
+unable to detect a 'package.json' file. This is likely because
+the '.gitignore' file is preventing it from being checked in to
+the git repo.
+
+For more information, refer to the following documentation:
+https://devcenter.heroku.com/articles/gitignore
+EOF
+else
+  error <<- EOF
+Application not supported by 'heroku/nodejs' buildpack
+
+The 'heroku/nodejs' buildpack is set on this application, but was
+unable to detect a Node.js codebase.
+    
+A Node.js app on Heroku requires a 'package.json' at the root of
+the directory structure.
+
+If you are trying to deploy a Node.js application, ensure that this
+file is present at the top level directory. This directory has the
+following files:
+
+$(ls -1p $1)
+    
+If you are trying to deploy an application written in another
+language, you need to change the list of buildpacks set on your
+Heroku app using the 'heroku buildpacks' command.
+    
+For more information, refer to the following documentation:
+https://devcenter.heroku.com/articles/buildpacks
+https://devcenter.heroku.com/articles/nodejs-support#activation
+EOF
+fi
+
 exit 1

bin/test-compile

 #!/usr/bin/env bash
 
-BP_DIR=$(cd $(dirname ${0:-}); cd ..; pwd)
+BP_DIR=$(cd "$(dirname ${0:-})"; cd ..; pwd)
 
 source $BP_DIR/lib/environment.sh
 

buildpack.toml

+[buildpack]
+name = "Node.js"
+
+  [publish.Ignore]
+  files = [
+      "etc/",
+      "test/",
+      ".github/",
+      ".travis.yml",
+      "makefile"
+  ]
\ No newline at end of file

etc/ci-setup.sh

+#!/usr/bin/env bash
+
+[ "$CI" != "true" ] && echo "Not running on CI!" && exit 1
+
+git config --global user.email ${HEROKU_API_USER:-"buildpack@example.com"}
+git config --global user.name 'BuildpackTester'
+
+cat <<EOF >> ~/.ssh/config
+Host heroku.com
+    StrictHostKeyChecking no
+    CheckHostIP no
+    UserKnownHostsFile=/dev/null
+Host github.com
+    StrictHostKeyChecking no
+EOF
+
+cat <<EOF >> ~/.netrc
+machine git.heroku.com
+  login ${HEROKU_API_USER:-"buildpack@example.com"}
+  password ${HEROKU_API_KEY:-"password"}
+EOF
+
+sudo apt-get -qq update
+sudo apt-get install software-properties-common -y
+curl --fail --retry 3 --retry-delay 1 --connect-timeout 3 --max-time 30 https://cli-assets.heroku.com/install-ubuntu.sh | sh
+
+if [ -n "$HEROKU_API_KEY" ]; then
+  yes | heroku keys:add
+fi

etc/hatchet.sh

+#!/usr/bin/env bash
+
+set -e
+
+if [ "$CIRCLECI" == "true" ] && [ -n "$CI_PULL_REQUEST" ]; then
+  if [ "$CIRCLE_PR_USERNAME" != "heroku" ]; then
+    echo "Skipping integration tests on forked PR."
+    exit 0
+  fi
+fi
+
+if [ "$TRAVIS" == "true" ] && [ "$TRAVIS_PULL_REQUEST" != "false" ]; then
+  if [ "$TRAVIS_PULL_REQUEST_SLUG" != "heroku/heroku-buildpack-nodejs" ]; then
+    echo "Skipping integration tests on forked PR."
+    exit 0
+  fi
+fi
+
+if [ -z "$HEROKU_API_KEY" ]; then
+  echo ""
+  echo "ERROR: Missing \$HEROKU_API_KEY."
+  echo ""
+  echo "NOTE: You can create token this by running: heroku authorizations:create --description \"For Travis\""
+  echo ""
+  exit 1
+fi
+
+if [ -n "$CIRCLE_BRANCH" ]; then
+  export HATCHET_BUILDPACK_BRANCH="$CIRCLE_BRANCH"
+elif [ -n "$TRAVIS_PULL_REQUEST_BRANCH" ]; then
+  export IS_RUNNING_ON_TRAVIS=true
+  export HATCHET_BUILDPACK_BRANCH="$TRAVIS_PULL_REQUEST_BRANCH"
+else
+  export HATCHET_BUILDPACK_BRANCH=$(git name-rev HEAD 2> /dev/null | sed 's#HEAD\ \(.*\)#\1#' | sed 's#tags\/##')
+fi
+
+gem install bundler
+bundle install
+
+export HATCHET_RETRIES=3
+export HATCHET_APP_LIMIT=20
+export HATCHET_DEPLOY_STRATEGY=git
+export HATCHET_BUILDPACK_BASE="https://github.com/heroku/heroku-buildpack-nodejs"
+
+bundle exec rspec "$@"

etc/publish.sh

+#!/bin/bash
+
+set -e
+
+BP_NAME=${1:-"heroku/nodejs"}
+
+curVersion=$(heroku buildpacks:versions "$BP_NAME" | awk 'FNR == 3 { print $1 }')
+newVersion="v$((curVersion + 1))"
+
+read -p "Deploy as version: $newVersion [y/n]? " choice
+case "$choice" in
+  y|Y ) echo "";;
+  n|N ) exit 0;;
+  * ) exit 1;;
+esac
+
+originMaster=$(git rev-parse origin/master)
+echo "Tagging commit $originMaster with $newVersion... "
+git tag "$newVersion" "${originMaster:?}"
+git push origin refs/tags/$newVersion
+
+heroku buildpacks:publish "$BP_NAME" "$newVersion"
+
+echo "Done."
\ No newline at end of file

hatchet.json

+{}

lib/binaries.sh

@@ -28,7 +28,7 @@ install_yarn() {
 
 install_nodejs() {
   local version=${1:-8.x}
-  local dir="$2"
+  local dir="${2:?}"
 
   echo "Resolving node version $version..."
   if ! read number url < <(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=$version" "https://nodebin.jxltom.com/v1/node/$platform/latest.txt"); then
@@ -41,7 +41,7 @@ install_nodejs() {
     echo "Unable to download node: $code" && false
   fi
   tar xzf /tmp/node.tar.gz -C /tmp
-  rm -rf $dir/*
+  rm -rf "$dir"/*
   mv /tmp/node-v$number-$os-$cpu/* $dir
   chmod +x $dir/bin/*
 }
@@ -79,14 +79,14 @@ install_npm() {
   fi
 
   if [ "$version" == "" ]; then
-    echo "Using default npm version: `npm --version`"
-  elif [[ `npm --version` == "$version" ]]; then
-    echo "npm `npm --version` already installed with node"
+    echo "Using default npm version: $npm_version"
+  elif [[ "$npm_version" == "$version" ]]; then
+    echo "npm $npm_version already installed with node"
   else
-    echo "Bootstrapping npm $version (replacing `npm --version`)..."
+    echo "Bootstrapping npm $version (replacing $npm_version)..."
     if ! npm install --unsafe-perm --quiet -g "npm@$version" 2>@1>/dev/null; then
       echo "Unable to install npm $version; does it exist?" && false
     fi
-    echo "npm `npm --version` installed"
+    echo "npm $version installed"
   fi
 }

lib/cache.sh

@@ -5,7 +5,7 @@ create_signature() {
 }
 
 save_signature() {
-  echo "$(create_signature)" > $CACHE_DIR/node/signature
+  create_signature > $CACHE_DIR/node/signature
 }
 
 load_signature() {
@@ -39,17 +39,41 @@ get_cache_directories() {
   fi
 }
 
-restore_cache_directories() {
+restore_default_cache_directories() {
   local build_dir=${1:-}
   local cache_dir=${2:-}
 
-  for cachepath in ${@:3}; do
+  # node_modules
+  if [[ -e "$build_dir/node_modules" ]]; then
+    echo "- node_modules is checked into source control and cannot be cached"
+  elif [[ -e "$cache_dir/node/node_modules" ]]; then
+    echo "- node_modules"
+    mkdir -p "$(dirname "$build_dir/node_modules")"
+    mv "$cache_dir/node/node_modules" "$build_dir/node_modules"
+  else
+    echo "- node_modules (not cached - skipping)"
+  fi
+
+  # bower_components, should be silent if it is not in the cache
+  if [[ -e "$cache_dir/node/bower_components" ]]; then
+    echo "- bower_components"
+  fi
+}
+
+restore_custom_cache_directories() {
+  local build_dir=${1:-}
+  local cache_dir=${2:-}
+  local cache_directories=("${@:3}")
+
+  echo "Loading ${#cache_directories[@]} from cacheDirectories (package.json):"
+
+  for cachepath in "${cache_directories[@]}"; do
     if [ -e "$build_dir/$cachepath" ]; then
       echo "- $cachepath (exists - skipping)"
     else
       if [ -e "$cache_dir/node/$cachepath" ]; then
         echo "- $cachepath"
-        mkdir -p $(dirname "$build_dir/$cachepath")
+        mkdir -p "$(dirname "$build_dir/$cachepath")"
         mv "$cache_dir/node/$cachepath" "$build_dir/$cachepath"
       else
         echo "- $cachepath (not cached - skipping)"
@@ -63,15 +87,42 @@ clear_cache() {
   mkdir -p $CACHE_DIR/node
 }
 
-save_cache_directories() {
+save_default_cache_directories() {
   local build_dir=${1:-}
   local cache_dir=${2:-}
 
-  for cachepath in ${@:3}; do
+  # node_modules
+  if [[ -e "$build_dir/node_modules" ]]; then
+    echo "- node_modules"
+    mkdir -p "$cache_dir/node/node_modules"
+    cp -a "$build_dir/node_modules" "$(dirname "$cache_dir/node/node_modules")"
+  else
+    # this can happen if there are no dependencies
+    mcount "cache.no-node-modules"
+    echo "- node_modules (nothing to cache)"
+  fi
+
+  # bower_components
+  if [[ -e "$build_dir/bower_components" ]]; then
+    mcount "cache.saved-bower-components"
+    echo "- bower_components"
+    mkdir -p "$cache_dir/node/bower_components"
+    cp -a "$build_dir/bower_components" "$(dirname "$cache_dir/node/bower_components")"
+  fi
+}
+
+save_custom_cache_directories() {
+  local build_dir=${1:-}
+  local cache_dir=${2:-}
+  local cache_directories=("${@:3}")
+
+  echo "Saving ${#cache_directories[@]} cacheDirectories (package.json):"
+
+  for cachepath in "${cache_directories[@]}"; do
     if [ -e "$build_dir/$cachepath" ]; then
       echo "- $cachepath"
       mkdir -p "$cache_dir/node/$cachepath"
-      cp -a "$build_dir/$cachepath" $(dirname "$cache_dir/node/$cachepath")
+      cp -a "$build_dir/$cachepath" "$(dirname "$cache_dir/node/$cachepath")"
     else
       echo "- $cachepath (nothing to cache)"
     fi

lib/dependencies.sh

 measure_size() {
-  echo "$((du -s node_modules 2>/dev/null || echo 0) | awk '{print $1}')"
+  (du -s node_modules 2>/dev/null || echo 0) | awk '{print $1}'
 }
 
 list_dependencies() {
@@ -21,10 +21,10 @@ run_if_present() {
   if [ -n "$has_script" ]; then
     if $YARN; then
       echo "Running $script_name (yarn)"
-      yarn run "$script_name"
+      monitor "$script_name" yarn run "$script_name"
     else
       echo "Running $script_name"
-      npm run "$script_name" --if-present
+      monitor "$script_name" npm run "$script_name" --if-present
     fi
   fi
 }
@@ -91,7 +91,7 @@ yarn_node_modules() {
 
   echo "Installing node modules (yarn.lock)"
   cd "$build_dir"
-  yarn install --production=$production --frozen-lockfile --ignore-engines 2>&1
+  monitor "yarn-install" yarn install --production=$production --frozen-lockfile --ignore-engines 2>&1
 }
 
 yarn_prune_devdependencies() {
@@ -107,10 +107,8 @@ yarn_prune_devdependencies() {
     echo "Skipping because YARN_PRODUCTION is '$YARN_PRODUCTION'"
     return 0
   else 
-    local start=$(nowms)
     cd "$build_dir" 
-    yarn install --frozen-lockfile --ignore-engines --ignore-scripts --prefer-offline 2>&1
-    mtime "prune.yarn.time" "${start}"
+    monitor "yarn-prune" yarn install --frozen-lockfile --ignore-engines --ignore-scripts --prefer-offline 2>&1
   fi
 }
 
@@ -128,7 +126,7 @@ npm_node_modules() {
     else
       echo "Installing node modules (package.json)"
     fi
-    npm install --production=$production --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
+    monitor "npm-install" npm install --production=$production --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
   else
     echo "Skipping (no package.json)"
   fi
@@ -147,7 +145,7 @@ npm_rebuild() {
     else
       echo "Installing any new modules (package.json)"
     fi
-    npm install --production=$production --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
+    monitor "npm-rebuild" npm install --production=$production --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
   else
     echo "Skipping (no package.json)"
   fi
@@ -189,9 +187,7 @@ npm_prune_devdependencies() {
     echo "https://devcenter.heroku.com/articles/nodejs-support#specifying-an-npm-version"
     return 0
   else
-    local start=$(nowms)
     cd "$build_dir" 
-    npm prune --userconfig $build_dir/.npmrc 2>&1
-    mtime "prune.npm.time" "${start}"
+    monitor "npm-prune" npm prune --userconfig $build_dir/.npmrc 2>&1
   fi
 }

lib/environment.sh

@@ -22,6 +22,14 @@ create_default_env() {
   export NODE_VERBOSE=${NODE_VERBOSE:-false}
 }
 
+create_build_env() {
+  # if the user hasn't set NODE_OPTIONS, increase the default amount of space
+  # that a node process can address to match that of the build dynos (2.5GB)
+  if [[ -z $NODE_OPTIONS ]]; then
+    export NODE_OPTIONS="--max_old_space_size=2560"
+  fi
+}
+
 list_node_config() {
   echo ""
   printenv | grep ^NPM_CONFIG_ || true
@@ -46,13 +54,14 @@ export_env_dir() {
   if [ -d "$env_dir" ]; then
     local whitelist_regex=${2:-''}
     local blacklist_regex=${3:-'^(PATH|GIT_DIR|CPATH|CPPATH|LD_PRELOAD|LIBRARY_PATH|LANG|BUILD_DIR)$'}
-    if [ -d "$env_dir" ]; then
-      for e in $(ls $env_dir); do
+    pushd "$env_dir" >/dev/null
+    for e in *; do
+      [ -e "$e" ] || continue
       echo "$e" | grep -E "$whitelist_regex" | grep -qvE "$blacklist_regex" &&
-        export "$e=$(cat $env_dir/$e)"
+      export "$e=$(cat $e)"
       :
     done
-    fi
+    popd >/dev/null
   fi
 }
 
@@ -73,6 +82,12 @@ write_ci_profile() {
 write_export() {
   local bp_dir="$1"
   local build_dir="$2"
+
+  # only write the export script if the buildpack directory is writable.
+  # this may occur in situations outside of Heroku, such as running the
+  # buildpacks locally.
+  if [ -w ${bp_dir} ]; then
     echo "export PATH=\"$build_dir/.heroku/node/bin:$build_dir/.heroku/yarn/bin:\$PATH:$build_dir/node_modules/.bin\"" > $bp_dir/export
     echo "export NODE_HOME=\"$build_dir/.heroku/node\"" >> $bp_dir/export
+  fi
 }

lib/failure.sh

@@ -450,9 +450,11 @@ log_other_failures() {
 warning() {
   local tip=${1:-}
   local url=${2:-https://devcenter.heroku.com/articles/nodejs-support}
-  echo "- $tip" >> $warnings
-  echo "  $url" >> $warnings
-  echo "" >> $warnings
+  {
+  echo "- $tip"
+  echo "  $url"
+  echo ""
+  } >> $warnings
 }
 
 warn() {

lib/kvstore.sh

+
+kv_create() {
+  local f=$1
+  mkdir -p $(dirname $f)
+  touch $f
+}
+
+kv_clear() {
+  local f=$1
+  echo "" > $f
+}
+
+kv_set() {
+  if [[ $# -eq 3 ]]; then
+    local f=$1
+    if [[ -f $f ]]; then
+      echo "$2=$3" >> $f
+    fi
+  fi
+}
+
+kv_get() {
+  if [[ $# -eq 2 ]]; then
+    local f=$1
+    if [[ -f $f ]]; then
+      grep "^$2=" $f | sed -e "s/^$2=//" | tail -n 1
+    fi
+  fi
+}
+
+kv_keys() {
+  local f=$1
+  local keys=()
+
+  if [[ -f $f ]]; then
+    # get list of keys
+    while IFS="=" read -r key value; do
+      keys+=("$key")
+    done < $f
+
+    echo "${keys[@]}" | tr ' ' '\n' | sort -u
+  fi
+}
+
+kv_list() {
+  local f=$1
+
+  kv_keys $f | tr ' ' '\n' | while read -r key; do
+    if [[ -n $key ]]; then
+      echo "$key=$(kv_get $f $key)"
+    fi
+  done
+}

lib/monitor.sh

+
+monitor_memory_usage() {
+  local output_file="$1"
+
+  # drop the first argument, and leave other arguments in place
+  shift
+
+  # Run the command in the background
+  "${@:-}" &
+
+  # save the PID of the running command
+  pid=$!
+
+  # if this build process is SIGTERM'd
+  trap "kill -TERM $pid" TERM
+
+  # set the peak memory usage to 0 to start
+  peak="0"
+
+  while true; do
+    sleep .1
+
+    # check the memory usage
+    sample="$(ps -o rss= $pid 2> /dev/null)" || break
+
+    if [[ $sample -gt $peak ]]; then
+      peak=$sample
+    fi
+  done
+
+  # ps gives us kb, let's convert to mb for convenience
+  echo "$(($peak / 1024))" > $output_file
+
+  # After wait returns we can get the exit code of $command
+  wait $pid
+
+  # wait a second time in case the trap was executed
+  # http://veithen.github.io/2014/11/16/sigterm-propagation.html
+  wait $pid
+
+  # return the exit code of $command
+  return $?
+}
+
+monitor() {
+  local command_name=$1
+  shift
+  local command="${@:-}"
+  local peak_mem_output=$(mktemp)
+  local start=$(nowms)
+
+  # execute the subcommand and save the peak memory usage
+  monitor_memory_usage $peak_mem_output $command
+
+  mtime "exec.$command_name.time" "${start}"
+  mmeasure "exec.$command_name.memory" "$(cat $peak_mem_output)"
+}

lib/output.sh

+# TODO: Merge these with the output helpers in buildpack-stdlib:
+# https://github.com/heroku/buildpack-stdlib
+
 info() {
   echo "       $*" || true
 }
@@ -6,9 +9,14 @@ info() {
 output() {
   local logfile="$1"
 
-  while read LINE;
+  while IFS= read -r LINE;
   do
+    # do not indent headers that are being piped through the output
+    if [[ "$LINE" =~ ^-----\>.* ]]; then
+      echo "$LINE" || true
+    else
       echo "       $LINE" || true
+    fi
     echo "$LINE" >> "$logfile" || true
   done
 }

lib/plugin.sh

+
+get_node_major_version() {
+  local node_version="$(node --version)"
+  # major_string will be ex: "6." "8." "10"
+  local major_string=${node_version:1:2}
+  # strip any "."s from major_string
+  local major=${major_string//.}
+  echo $major
+}
+
+install_plugin() {
+  local bp_dir="$1"
+  local build_dir="$2"
+  local major=$(get_node_major_version)
+  local plugin="${bp_dir}/plugin/heroku-nodejs-plugin-node-${major}.tar.gz"
+
+  # If we have a version of the plugin compiled for this version of node, and the
+  # user has not opted out of including the plugin, copy it into the slug.
+  # It will be included at runtime once the user opts into the Node metrics feature
+  if [[ -f "${plugin}" ]] && [[ -z "$HEROKU_SKIP_NODE_PLUGIN" ]]; then
+    mkdir -p "${build_dir}/.heroku/"
+    tar -xzf ${plugin} -C "${build_dir}/.heroku/"
+  fi
+}

makefile

-test: test-heroku-18 test-heroku-16 test-cedar-14
+test: heroku-18 heroku-16 cedar-14
 
-test-heroku-18:
+heroku-18:
 	@echo "Running tests in docker (heroku-18)..."
 	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-18" heroku/heroku:18 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
 	@echo ""
 
-test-heroku-16:
+heroku-16:
 	@echo "Running tests in docker (heroku-16)..."
 	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-16" heroku/heroku:16 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
 	@echo ""
 
-test-cedar-14:
+cedar-14:
 	@echo "Running tests in docker (cedar-14)..."
 	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=cedar-14" heroku/cedar:14 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
 	@echo ""
 
+hatchet:
+	@echo "Running hatchet integration tests..."
+	@bash etc/ci-setup.sh
+	@bash etc/hatchet.sh spec/ci/
+	@echo ""
+
+nodebin-test:
+	@echo "Running test for Node v${TEST_NODE_VERSION}..."
+	@bash etc/ci-setup.sh
+	@bash etc/hatchet.sh spec/nodebin/
+	@echo ""
+
+unit:
+	@echo "Running unit tests in docker (heroku-18)..."
+	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-18" heroku/heroku:18 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/unit;'
+	@echo ""
+
 shell:
 	@echo "Opening heroku-16 shell..."
 	@docker run -v $(shell pwd):/buildpack:ro --rm -it heroku/heroku:16 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; bash'

plugin/download.sh

+#!/usr/bin/env bash
+# download.sh <tag-name>
+
+set -o errexit    # always exit on error
+set -o pipefail   # don't ignore exit codes when piping output
+
+TAG_NAME=${1:-}
+PLUGIN_DIR=$(dirname $0)
+
+handle_failure() {
+    echo "Failure running script."
+
+    
+    echo "This may be rate-limiting from Github if you've run this script a few times. Here is the rate limit response:"
+    curl "https://api.github.com/rate_limit"
+}
+
+get_latest_release() {
+    # Get latest release tag from GitHub api
+    curl --silent --write-out "%{http_code}" "https://api.github.com/repos/heroku/heroku-nodejs-plugin/releases/latest" | 
+        grep '"tag_name":' | 
+        sed -E 's/.*"([^"]+)".*/\1/'                                    
+}
+
+download() {
+    local url=${1}
+    local file=${2}
+    local code=$(curl "$url" -L --fail --retry 5 --retry-max-time 15 -o "${file}" --write-out "%{http_code}")
+    if [[ "$code" != "200" ]]; then
+        echo "Unable to download from url: $url http code: $code"
+        exit 1
+    fi
+}
+
+delete_old_plugin() {
+    local dir=${1}
+    rm -f "$dir/heroku-nodejs-plugin-node-10.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-10.tar.gz"
+    rm -f "$dir/heroku-nodejs-plugin-node-8.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-8.tar.gz"
+    rm -f "$dir/heroku-nodejs-plugin-node-9.sha512"
+    rm -f "$dir/heroku-nodejs-plugin-node-9.tar.gz"
+    rm -f "$dir/version"
+}
+
+download_assets_for_release() {
+    local tag=${1}
+    local dir=${2}
+
+    # Node 8
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-8-$tag.sha512" "$dir/heroku-nodejs-plugin-node-8.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-8-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-8.tar.gz"
+
+    # Node 9
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-9-$tag.sha512" "$dir/heroku-nodejs-plugin-node-9.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-9-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-9.tar.gz"
+
+    # Node 10 
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-10-$tag.sha512" "$dir/heroku-nodejs-plugin-node-10.sha512"
+    download "https://github.com/heroku/heroku-nodejs-plugin/releases/download/$tag/heroku-nodejs-plugin-node-10-$tag.tar.gz" "$dir/heroku-nodejs-plugin-node-10.tar.gz"
+}
+
+test_hash() {
+    local major=${1}
+    local dir=${2}
+
+    local downloaded_sha=$(cat $dir/heroku-nodejs-plugin-node-$major.sha512 | awk '{print substr($0,0,128)}')
+    local binary_sha=$(shasum -a 512 $dir/heroku-nodejs-plugin-node-$major.tar.gz | awk '{print substr($0,0,128)}')
+
+    if [[ "$downloaded_sha" != "$binary_sha" ]]; then
+        echo "Invalid SHA for file: $dir/heroku-nodejs-plugin-node-$major.tar.gz"
+        exit 1
+    else
+        echo "Verified SHA for file: $dir/heroku-nodejs-plugin-node-$major.tar.gz"
+    fi
+}
+
+trap 'handle_failure' ERR
+
+if [[ -z $TAG_NAME ]]; then
+    TAG_NAME=$(get_latest_release)
+fi
+
+echo "Removing any old versions of the plugin"
+delete_old_plugin $PLUGIN_DIR
+
+echo "Downloading plugins"
+download_assets_for_release $TAG_NAME $PLUGIN_DIR
+echo $TAG_NAME > "$PLUGIN_DIR/version"
+
+echo "Plugins downloaded"
+
+test_hash 8 $PLUGIN_DIR
+test_hash 9 $PLUGIN_DIR
+test_hash 10 $PLUGIN_DIR
+
+echo "Done"

plugin/heroku-nodejs-plugin-node-10.sha512

+1af8d337d1bdbdbddd76a64e8d2a802729d26b4decfaf2b7cbc530c436575a31053b5cac5afc7b40e76ddb2fce5b6c96f3dc851dc0b6495693c5e3672f615675  heroku-nodejs-plugin-node-10-v3.tar.gz

plugin/heroku-nodejs-plugin-node-8.sha512

+314f894633ce4eb7aea2577a125cac9f08b3a53e46b8f4930f283603eaef0ff4fc08e8b3dc31c06d28383f9f24355b8bb1a8c6cac881d557fc25b6718ae204f7  heroku-nodejs-plugin-node-8-v3.tar.gz

plugin/heroku-nodejs-plugin-node-9.sha512

+58ece877a2e0a9790a1e2c17936c2e9b224736015c5183a1e070ac4c08631bdcc131fb81db9b1d07a4819b946dd7cce1b1b7e2f7b512f350f81d1e69672bc009  heroku-nodejs-plugin-node-9-v3.tar.gz

plugin/version

+v3

profile/WEB_CONCURRENCY.sh

@@ -20,7 +20,7 @@ detect_memory() {
   local default=$1
 
   if [ -e /sys/fs/cgroup/memory/memory.limit_in_bytes ]; then
-    expr "$(cat /sys/fs/cgroup/memory/memory.limit_in_bytes)" / 1048576
+    echo $(($(cat /sys/fs/cgroup/memory/memory.limit_in_bytes) / 1048576))
   else
     echo "$default"
   fi

profile/nodejs.sh

 export PATH="$HOME/.heroku/node/bin:$HOME/.heroku/yarn/bin:$PATH:$HOME/bin:$HOME/node_modules/.bin"
 export NODE_HOME="$HOME/.heroku/node"
 export NODE_ENV=${NODE_ENV:-production}
+
+# If the user has opted into the feature
+if [[ -n "$HEROKU_METRICS_URL" ]] && \
+   # if we're not on a one-off dyno
+   [[ "${DYNO}" != run\.* ]] && \
+   # if the plugin was installed for this node version
+   [[ -d $HOME/.heroku/heroku-nodejs-plugin ]] && \
+   # the user has not opted out
+   [[ -z "$HEROKU_SKIP_NODE_PLUGIN" ]]; then
+
+  # Don't clobber NODE_OPTIONS if the user has set it, just add the require flag to the end
+  if [[ -z "$NODE_OPTIONS" ]]; then
+      export NODE_OPTIONS="--require $HOME/.heroku/heroku-nodejs-plugin"
+  else
+      export NODE_OPTIONS="${NODE_OPTIONS} --require $HOME/.heroku/heroku-nodejs-plugin"
+  fi
+
+fi

spec/ci/node_10_metrics_spec.rb

+require_relative '../spec_helper'
+
+describe "Node Metrics for v10.x" do
+  context "test metrics for Node v10.x app" do
+    let(:app) {
+      Hatchet::Runner.new(
+        "spec/fixtures/repos/node-10-metrics",
+        config: {
+          "HEROKU_METRICS_URL" => "http://localhost:3000",
+          "METRICS_INTERVAL_OVERRIDE" => "10000"
+        }
+      )
+    }
+
+    it "should deploy" do
+      app.deploy do |app|
+        data = successful_json_body(app)
+        expect(data["gauges"]["node.eventloop.delay.ms.max"]).to be >= 2000
+        expect(data["counters"]["node.gc.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.young.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.old.collections"]).to be >= 0
+      end
+    end
+  end
+end

spec/ci/node_10_spec.rb

+require_relative '../spec_helper'
+
+describe "Hello World for Node v10.x" do
+  context "a single-process Node v10.x app" do
+    let(:app) {
+      Hatchet::Runner.new("spec/fixtures/repos/node-10")
+    }
+
+    it "should deploy successfully" do
+      app.deploy do |app|
+        expect(successful_body(app).strip).to eq("Hello, world!")
+      end
+    end
+
+  end
+end

spec/ci/node_6_spec.rb

+require_relative '../spec_helper'
+
+describe "Hello World for Node v6.x" do
+  context "a single-process Node v6.x app" do
+    let(:app) {
+      Hatchet::Runner.new("spec/fixtures/repos/node-6")
+    }
+
+    it "should deploy successfully" do
+      app.deploy do |app|
+        expect(successful_body(app).strip).to eq("Hello, world!")
+      end
+    end
+
+  end
+end

spec/ci/node_8_metrics_spec.rb

+require_relative '../spec_helper'
+
+describe "Node Metrics for v8.x" do
+  context "test metrics for Node v8.x app" do
+    let(:app) {
+      Hatchet::Runner.new(
+        "spec/fixtures/repos/node-8-metrics",
+        config: {
+          "HEROKU_METRICS_URL" => "http://localhost:3000",
+          "METRICS_INTERVAL_OVERRIDE" => "10000"
+        }
+      )
+    }
+
+    it "should deploy" do
+      app.deploy do |app|
+        data = successful_json_body(app)
+        expect(data["gauges"]["node.eventloop.delay.ms.max"]).to be >= 2000
+        expect(data["counters"]["node.gc.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.young.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.old.collections"]).to be >= 0
+      end
+    end
+  end
+end

spec/ci/node_8_spec.rb

+require_relative '../spec_helper'
+
+describe "Hello World for Node v8.x" do
+  context "a single-process Node v8.x app" do
+    let(:app) {
+      Hatchet::Runner.new(
+        "spec/fixtures/repos/node-8"
+      )
+    }
+
+    it "should deploy successfully" do
+      app.deploy do |app|
+        expect(successful_body(app).strip).to eq("Hello, world!")
+      end
+    end
+
+  end
+end

spec/ci/node_9_metrics_spec.rb

+require_relative '../spec_helper'
+
+describe "Node Metrics for v9.x" do
+  context "test metrics for Node v9.x app" do
+    let(:app) {
+      Hatchet::Runner.new(
+        "spec/fixtures/repos/node-9-metrics",
+        config: {
+          "HEROKU_METRICS_URL" => "http://localhost:3000",
+          "METRICS_INTERVAL_OVERRIDE" => "10000"
+        }
+      )
+    }
+
+    it "should deploy" do
+      app.deploy do |app|
+        data = successful_json_body(app)
+        expect(data["gauges"]["node.eventloop.delay.ms.max"]).to be >= 2000
+        expect(data["counters"]["node.gc.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.young.collections"]).to be >= 0
+        expect(data["counters"]["node.gc.old.collections"]).to be >= 0
+      end
+    end
+  end
+end

spec/ci/node_9_spec.rb

+require_relative '../spec_helper'
+
+describe "Hello World for Node v9.x" do
+  context "a single-process Node v9.x app" do
+    let(:app) {
+      Hatchet::Runner.new("spec/fixtures/repos/node-9")
+    }
+
+    it "should deploy successfully" do
+      app.deploy do |app|
+        expect(successful_body(app).strip).to eq("Hello, world!")
+      end
+    end
+
+  end
+end

spec/ci/node_metrics_conflict_spec.rb

+require_relative '../spec_helper'
+
+describe "Node metrics plugin should not fail other Node binaries" do
+  context "an app that runs the Heroku CLI with metrics" do
+    let(:app) {
+      Hatchet::Runner.new(
+        "spec/fixtures/repos/node-metrics-conflict",
+        buildpacks: [
+          Hatchet::App.default_buildpack,
+          "https://github.com/heroku/heroku-buildpack-cli"
+        ],
+        config: {
+          "HEROKU_METRICS_URL" => "http://localhost:3000"
+        }
+      )
+    }
+
+    it "should not run within the heroku cli" do
+      app.deploy do |app|
+        data = successful_body(app)
+        expect(data).to include("not logged in")
+        expect(data).not_to include("was compiled against a different Node.js version")
+      end
+    end
+  end
+end

spec/fixtures/repos/node-10-metrics/Procfile

+web: node src/index.js

spec/fixtures/repos/node-10-metrics/package.json

+{
+  "name": "node-metrics-test-app",
+  "version": "1.0.0",
+  "engines": {
+    "node": "10.x"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {},
+  "dependencies": {}
+}

spec/fixtures/repos/node-10-metrics/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const EventEmitter = require('events');
+
+const PORT = process.env.PORT || 5000;
+const Events = new EventEmitter();
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      console.log(`blocking the event loop for ${ms}ms`);
+      let now = new Date().getTime();
+      let result = 0
+      while(true) {
+        result += Math.random() * Math.random();
+        if (new Date().getTime() > now + ms)
+          break;
+      }
+      resolve();
+    }, 100);
+  });
+}
+
+function getNextMetricsEvent() {
+  return new Promise((resolve, reject) => Events.once('metrics', resolve));
+}
+
+const server = http.createServer((req, res) => {
+  // wait for the next metrics event
+  getNextMetricsEvent()
+    .then(blockCpuFor(2000))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    // gather the next metrics data which should include these pauses
+    .then(getNextMetricsEvent())
+    .then(data => {
+      res.setHeader('Content-Type', 'application/json');
+      res.end(data); 
+    })
+    .catch(() => {
+      res.statusCode = 500;
+      res.end("Something went wrong"); 
+    });
+});
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));
+
+// Create a second server that intercepts the HTTP requests
+// sent by the metrics plugin
+const metricsListener = http.createServer((req, res) => {
+  if (req.method == 'POST') {
+    let body = '';
+    req.on('data', (data) => body += data);
+    req.on('end', () => Events.emit('metrics', body));
+    res.statusCode = 200;
+    res.end();
+  }
+});
+
+metricsListener.listen(3000, () => console.log('Listening for metrics on 3000'));
+

spec/fixtures/repos/node-10/Procfile

+web: node src/index.js

spec/fixtures/repos/node-10/app.json

+{
+  "name": "hello-world"
+}

spec/fixtures/repos/node-10/package.json

+{
+  "name": "hello-world",
+  "version": "1.0.0",
+  "engines": {
+    "node": "10.x"
+  },
+  "scripts": {
+    "prettify": "prettier --single-quote --trailing-comma all --write 'bin/*' 'src/**/*.js'",
+    "test": "jest --silent",
+    "dev": "nodemon --watch . --watch src/* src/index.js",
+    "heroku-postbuild": "echo NODE_OPTIONS: $NODE_OPTIONS"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {
+    "jest": "^19.0.2",
+    "nodemon": "^1.11.0",
+    "prettier": "^0.22.0"
+  },
+  "dependencies": {}
+}

spec/fixtures/repos/node-10/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const crypto = require('crypto');
+
+const PORT = process.env.PORT || 5000;
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+	var now = new Date().getTime();
+	var result = 0
+	while(true) {
+		result += Math.random() * Math.random();
+		if (new Date().getTime() > now +ms)
+			return;
+	}
+}
+
+// block the event loop for 100ms every second
+setInterval(() => {
+  blockCpuFor(100);
+}, 1000)
+
+// block the event loop for 1sec every 30 seconds
+setInterval(() => {
+  blockCpuFor(1000);
+}, 30000)
+
+// Allocate and erase memory on an interval
+let store = [];
+
+setInterval(() => {
+  store.push(crypto.randomBytes(1000000).toString('hex'));
+}, 500);
+
+setInterval(() => {
+  store = [];
+}, 60000);
+
+const server = http.createServer((req, res) => {
+  res.statusCode = 200;
+  res.setHeader('Content-Type', 'text/plain');
+  res.end("Hello, world!");
+})
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));

spec/fixtures/repos/node-6/Procfile

+web: node src/index.js

spec/fixtures/repos/node-6/app.json

+{
+  "name": "hello-world"
+}

spec/fixtures/repos/node-6/package.json

+{
+  "name": "hello-world",
+  "version": "1.0.0",
+  "engines": {
+    "node": "6.x"
+  },
+  "scripts": {
+    "prettify": "prettier --single-quote --trailing-comma all --write 'bin/*' 'src/**/*.js'",
+    "test": "jest --silent",
+    "dev": "nodemon --watch . --watch src/* src/index.js",
+    "heroku-postbuild": "echo NODE_OPTIONS: $NODE_OPTIONS"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {
+    "jest": "^19.0.2",
+    "nodemon": "^1.11.0",
+    "prettier": "^0.22.0"
+  },
+  "dependencies": {}
+}

spec/fixtures/repos/node-6/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const crypto = require('crypto');
+
+const PORT = process.env.PORT || 5000;
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+	var now = new Date().getTime();
+	var result = 0
+	while(true) {
+		result += Math.random() * Math.random();
+		if (new Date().getTime() > now +ms)
+			return;
+	}
+}
+
+// block the event loop for 100ms every second
+setInterval(() => {
+  blockCpuFor(100);
+}, 1000)
+
+// block the event loop for 1sec every 30 seconds
+setInterval(() => {
+  blockCpuFor(1000);
+}, 30000)
+
+// Allocate and erase memory on an interval
+let store = [];
+
+setInterval(() => {
+  store.push(crypto.randomBytes(1000000).toString('hex'));
+}, 500);
+
+setInterval(() => {
+  store = [];
+}, 60000);
+
+const server = http.createServer((req, res) => {
+  res.statusCode = 200;
+  res.setHeader('Content-Type', 'text/plain');
+  res.end("Hello, world!");
+})
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));

spec/fixtures/repos/node-8-metrics/Procfile

+web: node src/index.js

spec/fixtures/repos/node-8-metrics/package.json

+{
+  "name": "node-metrics-test-app",
+  "version": "1.0.0",
+  "engines": {
+    "node": "8.x"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {},
+  "dependencies": {}
+}

spec/fixtures/repos/node-8-metrics/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const EventEmitter = require('events');
+
+const PORT = process.env.PORT || 5000;
+const Events = new EventEmitter();
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      console.log(`blocking the event loop for ${ms}ms`);
+      let now = new Date().getTime();
+      let result = 0
+      while(true) {
+        result += Math.random() * Math.random();
+        if (new Date().getTime() > now + ms)
+          break;
+      }
+      resolve();
+    }, 100);
+  });
+}
+
+function getNextMetricsEvent() {
+  return new Promise((resolve, reject) => Events.once('metrics', resolve));
+}
+
+const server = http.createServer((req, res) => {
+  // wait for the next metrics event
+  getNextMetricsEvent()
+    .then(blockCpuFor(2000))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    // gather the next metrics data which should include these pauses
+    .then(getNextMetricsEvent())
+    .then(data => {
+      res.setHeader('Content-Type', 'application/json');
+      res.end(data); 
+    })
+    .catch(() => {
+      res.statusCode = 500;
+      res.end("Something went wrong"); 
+    });
+});
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));
+
+// Create a second server that intercepts the HTTP requests
+// sent by the metrics plugin
+const metricsListener = http.createServer((req, res) => {
+  if (req.method == 'POST') {
+    let body = '';
+    req.on('data', (data) => body += data);
+    req.on('end', () => Events.emit('metrics', body));
+    res.statusCode = 200;
+    res.end();
+  }
+});
+
+metricsListener.listen(3000, () => console.log('Listening for metrics on 3000'));
+

spec/fixtures/repos/node-8/Procfile

+web: node src/index.js

spec/fixtures/repos/node-8/app.json

+{
+  "name": "hello-world"
+}

spec/fixtures/repos/node-8/package.json

+{
+  "name": "hello-world",
+  "version": "1.0.0",
+  "engines": {
+    "node": "8.x"
+  },
+  "scripts": {
+    "prettify": "prettier --single-quote --trailing-comma all --write 'bin/*' 'src/**/*.js'",
+    "test": "jest --silent",
+    "dev": "nodemon --watch . --watch src/* src/index.js",
+    "heroku-postbuild": "echo NODE_OPTIONS: $NODE_OPTIONS"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {
+    "jest": "^19.0.2",
+    "nodemon": "^1.11.0",
+    "prettier": "^0.22.0"
+  },
+  "dependencies": {}
+}

spec/fixtures/repos/node-8/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const crypto = require('crypto');
+
+const PORT = process.env.PORT || 5000;
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+	var now = new Date().getTime();
+	var result = 0
+	while(true) {
+		result += Math.random() * Math.random();
+		if (new Date().getTime() > now +ms)
+			return;
+	}
+}
+
+// block the event loop for 100ms every second
+setInterval(() => {
+  blockCpuFor(100);
+}, 1000)
+
+// block the event loop for 1sec every 30 seconds
+setInterval(() => {
+  blockCpuFor(1000);
+}, 30000)
+
+// Allocate and erase memory on an interval
+let store = [];
+
+setInterval(() => {
+  store.push(crypto.randomBytes(1000000).toString('hex'));
+}, 500);
+
+setInterval(() => {
+  store = [];
+}, 60000);
+
+const server = http.createServer((req, res) => {
+  res.statusCode = 200;
+  res.setHeader('Content-Type', 'text/plain');
+  res.end("Hello, world!");
+})
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));

spec/fixtures/repos/node-9-metrics/Procfile

+web: node src/index.js

spec/fixtures/repos/node-9-metrics/package.json

+{
+  "name": "node-metrics-test-app",
+  "version": "1.0.0",
+  "engines": {
+    "node": "9.x"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {},
+  "dependencies": {}
+}

spec/fixtures/repos/node-9-metrics/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const EventEmitter = require('events');
+
+const PORT = process.env.PORT || 5000;
+const Events = new EventEmitter();
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+  return new Promise((resolve, reject) => {
+    setTimeout(() => {
+      console.log(`blocking the event loop for ${ms}ms`);
+      let now = new Date().getTime();
+      let result = 0
+      while(true) {
+        result += Math.random() * Math.random();
+        if (new Date().getTime() > now + ms)
+          break;
+      }
+      resolve();
+    }, 100);
+  });
+}
+
+function getNextMetricsEvent() {
+  return new Promise((resolve, reject) => Events.once('metrics', resolve));
+}
+
+const server = http.createServer((req, res) => {
+  // wait for the next metrics event
+  getNextMetricsEvent()
+    .then(blockCpuFor(2000))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    .then(blockCpuFor(100))
+    // gather the next metrics data which should include these pauses
+    .then(getNextMetricsEvent())
+    .then(data => {
+      res.setHeader('Content-Type', 'application/json');
+      res.end(data); 
+    })
+    .catch(() => {
+      res.statusCode = 500;
+      res.end("Something went wrong"); 
+    });
+});
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));
+
+// Create a second server that intercepts the HTTP requests
+// sent by the metrics plugin
+const metricsListener = http.createServer((req, res) => {
+  if (req.method == 'POST') {
+    let body = '';
+    req.on('data', (data) => body += data);
+    req.on('end', () => Events.emit('metrics', body));
+    res.statusCode = 200;
+    res.end();
+  }
+});
+
+metricsListener.listen(3000, () => console.log('Listening for metrics on 3000'));
+

spec/fixtures/repos/node-9/Procfile

+web: node src/index.js

spec/fixtures/repos/node-9/app.json

+{
+  "name": "hello-world"
+}

spec/fixtures/repos/node-9/package.json

+{
+  "name": "hello-world",
+  "version": "1.0.0",
+  "engines": {
+    "node": "9.x"
+  },
+  "scripts": {
+    "prettify": "prettier --single-quote --trailing-comma all --write 'bin/*' 'src/**/*.js'",
+    "test": "jest --silent",
+    "dev": "nodemon --watch . --watch src/* src/index.js",
+    "heroku-postbuild": "echo NODE_OPTIONS: $NODE_OPTIONS"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {
+    "jest": "^19.0.2",
+    "nodemon": "^1.11.0",
+    "prettier": "^0.22.0"
+  },
+  "dependencies": {}
+}

spec/fixtures/repos/node-9/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const crypto = require('crypto');
+
+const PORT = process.env.PORT || 5000;
+
+// This will block the event loop for ~lengths of time
+function blockCpuFor(ms) {
+	var now = new Date().getTime();
+	var result = 0
+	while(true) {
+		result += Math.random() * Math.random();
+		if (new Date().getTime() > now +ms)
+			return;
+	}
+}
+
+// block the event loop for 100ms every second
+setInterval(() => {
+  blockCpuFor(100);
+}, 1000)
+
+// block the event loop for 1sec every 30 seconds
+setInterval(() => {
+  blockCpuFor(1000);
+}, 30000)
+
+// Allocate and erase memory on an interval
+let store = [];
+
+setInterval(() => {
+  store.push(crypto.randomBytes(1000000).toString('hex'));
+}, 500);
+
+setInterval(() => {
+  store = [];
+}, 60000);
+
+const server = http.createServer((req, res) => {
+  res.statusCode = 200;
+  res.setHeader('Content-Type', 'text/plain');
+  res.end("Hello, world!");
+})
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));

spec/fixtures/repos/node-metrics-conflict/Procfile

+web: node src/index.js

spec/fixtures/repos/node-metrics-conflict/package.json

+{
+  "name": "node-metrics-test-app",
+  "version": "1.0.0",
+  "engines": {
+    "node": "8.x"
+  },
+  "main": "index.js",
+  "license": "MIT",
+  "devDependencies": {},
+  "dependencies": {}
+}

spec/fixtures/repos/node-metrics-conflict/src/index.js

+#!/usr/bin/env node
+
+const http = require('http');
+const exec = require('child_process').exec;
+const PORT = process.env.PORT || 5000;
+
+const server = http.createServer((req, res) => {
+  /*
+    Note: we cannot use `heroku run` to test this since the metrics plugin is
+          disabled on run dynos
+  */
+  exec('heroku whoami', (error, stdout, stderr) => {
+    res.statusCode = 200;
+    res.setHeader('Content-Type', 'text/plain');
+    res.end(stderr);
+  });
+})
+
+server.listen(PORT, () => console.log(`Listening on ${PORT}`));

spec/nodebin/node_vX_metrics_spec.rb

+require_relative '../spec_helper'
+
+versions = get_test_versions
+
+versions.select { |version| version_supports_metrics(version) }.each do |version|
+  describe "Node Metrics for v#{version}" do
+    context "test metrics for Node v#{version} app" do
+      let(:app) {
+        Hatchet::Runner.new(
+          "spec/fixtures/repos/node-10-metrics",
+          before_deploy: -> { set_node_version(version) },
+          config: {
+            "HEROKU_METRICS_URL" => "http://localhost:3000",
+            "METRICS_INTERVAL_OVERRIDE" => "10000"
+          }
+        )
+      }
+
+      it "should deploy" do
+        app.deploy do |app|
+          expect(app.output).to include("Downloading and installing node #{version}...")
+          data = successful_json_body(app)
+          expect(data["gauges"]["node.eventloop.delay.ms.max"]).to be >= 2000
+          expect(data["counters"]["node.gc.collections"]).to be >= 0
+          expect(data["counters"]["node.gc.young.collections"]).to be >= 0
+          expect(data["counters"]["node.gc.old.collections"]).to be >= 0
+        end
+      end
+    end
+  end
+end

spec/nodebin/node_vX_spec.rb

+require_relative '../spec_helper'
+
+versions = get_test_versions
+
+versions.each do |version|
+  describe "Hello World for Node v#{version}" do
+    context "a single-process Node v#{version} app" do
+      let(:app) {
+        Hatchet::Runner.new(
+          "spec/fixtures/repos/node-10",
+          before_deploy: -> { set_node_version(version) }
+        )
+      }
+
+      it "should deploy successfully" do
+        app.deploy do |app|
+          expect(app.output).to include("Downloading and installing node #{version}...")
+          expect(successful_body(app).strip).to eq("Hello, world!")
+        end
+      end
+    end
+  end
+end

spec/spec_helper.rb

+require 'rspec/core'
+require 'hatchet'
+require 'fileutils'
+require 'hatchet'
+require 'rspec/retry'
+require 'date'
+require 'json'
+require 'sem_version'
+
+ENV['RACK_ENV'] = 'test'
+
+RSpec.configure do |config|
+  config.filter_run focused: true unless ENV['IS_RUNNING_ON_TRAVIS']
+  config.run_all_when_everything_filtered = true
+  config.alias_example_to :fit, focused: true
+  config.full_backtrace      = true
+  config.verbose_retry       = true # show retry status in spec process
+  config.default_retry_count = 2 if ENV['IS_RUNNING_ON_TRAVIS'] # retry all tests that fail again
+
+  config.expect_with :rspec do |c|
+    c.syntax = :expect
+  end
+end
+
+def successful_body(app, options = {})
+  retry_limit = options[:retry_limit] || 100 
+  path = options[:path] ? "/#{options[:path]}" : ''
+  Excon.get("http://#{app.name}.herokuapp.com#{path}", :idempotent => true, :expects => 200, :retry_limit => retry_limit).body
+end
+
+def successful_json_body(app, options = {})
+  body = successful_body(app, options)
+  JSON.parse(body)
+end
+
+def set_node_version(version)
+  package_json = File.read('package.json')
+  package = JSON.parse(package_json)
+  package["engines"]["node"] = version
+  File.open('package.json', 'w') do |f|
+    f.puts JSON.dump(package)
+  end
+end
+
+def resolve_node_version(requirements, options = {})
+  # use nodebin to get latest node versions
+  requirements.map do |requirement|
+    retry_limit = options[:retry_limit] || 50
+    body = Excon.get("https://nodebin.herokai.com/v1/node/linux-x64/latest?range=#{requirement}", :idempotent => true, :expects => 200, :retry_limit => retry_limit).body
+    JSON.parse(body)['number']
+  end
+end
+
+def resolve_all_supported_node_versions(options = {})
+  retry_limit = options[:retry_limit] || 50 
+  body = Excon.get("https://nodebin.herokai.com/v1/node/linux-x64/", :idempotent => true, :expects => 200, :retry_limit => retry_limit).body
+  list = JSON.parse(body).map { |n| n['number'] }
+
+  list.select do |n|
+    SemVersion.new(n).satisfies?('>= 6.0.0')
+  end
+end
+
+def version_supports_metrics(version)
+  SemVersion.new(version).satisfies?('>= 8.0.0')
+end
+
+def get_test_versions
+  if ENV['TEST_NODE_VERSION']
+    versions = [ENV['TEST_NODE_VERSION']]
+  elsif ENV['TEST_ALL_NODE_VERSIONS'] == 'true'
+    versions = resolve_all_supported_node_versions()
+  else
+    versions = resolve_node_version(['6.x', '8.x', '9.x', '10.x'])
+  end
+  puts("Running tests for Node versions: #{versions.join(', ')}")
+  versions
+end

test/fixtures/gitignore-package-json/.gitignore

+package.json

test/fixtures/node-10/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/node-10/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+    "hashish": "*"
+  },
+  "engines": {
+    "node": "10.x"
+  },
+  "scripts": {
+    "start": "node foo.js"
+  }
+}

test/fixtures/node-6/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/node-6/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+    "hashish": "*"
+  },
+  "engines": {
+    "node": "6.x"
+  },
+  "scripts": {
+    "start": "node foo.js"
+  }
+}

test/fixtures/node-8/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/node-8/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+    "hashish": "*"
+  },
+  "engines": {
+    "node": "8.x"
+  },
+  "scripts": {
+    "start": "node foo.js"
+  }
+}

test/fixtures/node-9/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/node-9/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+    "hashish": "*"
+  },
+  "engines": {
+    "node": "9.x"
+  },
+  "scripts": {
+    "start": "node foo.js"
+  }
+}

test/fixtures/print-node-options/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/print-node-options/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+    "hashish": "*"
+  },
+  "engines": {
+    "node": "8.x"
+  },
+  "scripts": {
+    "start": "node foo.js",
+    "heroku-postbuild": "echo NODE_OPTIONS=$NODE_OPTIONS"
+  }
+}

test/fixtures/slugignore-package-json/.slugignore

+package.json

test/fixtures/yarn/package.json

@@ -3,6 +3,9 @@
   "version": "1.0.0",
   "main": "index.js",
   "license": "MIT",
+  "engines": {
+    "yarn": "1.x"
+  },
   "dependencies": {
     "lodash": "^4.16.4"
   }

test/quick

 #!/usr/bin/env bash
 
-source $(pwd)/lib/environment.sh
+source "$(pwd)"/lib/environment.sh
 
 mktmpdir() {
   local dir=$(mktemp -t testXXXXX)
@@ -18,7 +18,7 @@ compile() {
   echo "Compiling $fixture"
   echo "in $build_dir"
   echo "(caching in $cache_dir)"
-  cp -a $(pwd)/* ${bp_dir}
+  cp -a "$(pwd)"/* ${bp_dir}
   cp -a ${bp_dir}/test/fixtures/$fixture/. ${build_dir}
   "$bp_dir/bin/compile" "$build_dir" "$cache_dir"
 }
@@ -32,7 +32,7 @@ compileTest() {
   echo "Compiling $fixture"
   echo "in $build_dir"
   echo "(caching in $cache_dir)"
-  cp -a $(pwd)/* ${bp_dir}
+  cp -a "$(pwd)"/* ${bp_dir}
   cp -a ${bp_dir}/test/fixtures/$fixture/. ${build_dir}
   "$bp_dir/bin/test-compile" "$build_dir" "$cache_dir"
 

test/unit

+#!/usr/bin/env bash
+
+# testing monitor_memory_usage
+
+# allocate ~14 mb of memory and wait a bit
+use_memory() {
+  for index in $(seq 10); do
+    value=$(seq -w -s '' $index $(($index + 100000)))
+    eval array$index=$value
+  done
+  sleep 0.5
+}
+
+# print each argument to a separate line on stdout
+print_args() {
+  while (( "$#" )); do 
+    echo $1 
+    shift 
+  done
+}
+
+testMonitorMemory() {
+  local mem_output=$(mktemp)
+  local stdout_capture=$(mktemp)
+
+  monitor_memory_usage $mem_output echo "this is a test" > /dev/null
+  assertTrue "should use less than 2mb" "[[ $(cat $mem_output) -lt 2 ]]"
+
+  monitor_memory_usage $mem_output use_memory
+  assertTrue "should use more than 10mb" "[[ $(cat $mem_output) -gt 10 ]]"
+
+  monitor_memory_usage $mem_output print_args --foo --bar="baz lol hi" > $stdout_capture
+  assertTrue "should use less than 2mb" "[[ $(cat $mem_output) -lt 2 ]]"
+  assertTrue "should output 2 lines" "[[ $(wc -l < $stdout_capture) -eq 2 ]]"
+  assertEquals "first line" "--foo" "$(head -n 1 $stdout_capture)"
+  assertEquals "second line" "--bar=baz lol hi" "$(tail -n 1 $stdout_capture)"
+}
+
+testOutput() {
+  local stdout
+
+  stdout=$(echo '    Indented line' | output /dev/null)
+  assertEquals 'should preserve leading whitespace' '           Indented line' "${stdout}"
+
+  stdout=$(echo 'Foo \ bar' | output /dev/null)
+  assertEquals 'should preserve unescaped backslashes' '       Foo \ bar' "${stdout}"
+}
+
+testKeyValue() {
+  local store=$(mktemp)
+
+  kv_create $store
+
+  kv_set $store key value
+  kv_set $store foo bar
+  kv_set $store key other_value
+  kv_set $store bar baz
+
+  assertEquals "other_value" "$(kv_get $store key)"
+  assertEquals "bar" "$(kv_get $store foo)"
+  assertEquals "baz" "$(kv_get $store bar)"
+
+  # if the key isn't there it should return an empty string
+  assertEquals "" "$(kv_get $store not_there)"
+
+  # kv_keys returns each key on a new line
+  assertEquals "$(printf "%s\n" bar foo key)" "$(kv_keys $store)"
+
+  # kv_list returns key=value on individual lines
+  assertEquals "$(printf "%s\n" bar=baz foo=bar key=other_value)" "$(kv_list $store)"
+
+  # calling create on an existing store doesn't erase it
+  kv_create $store
+  assertEquals "$(printf "%s\n" bar=baz foo=bar key=other_value)" "$(kv_list $store)"
+
+  # now clear the store
+  kv_clear $store
+
+  assertEquals "" "$(kv_get $store key)"
+  assertEquals "" "$(kv_keys $store)"
+  assertEquals "" "$(kv_list $store)"
+}
+
+# if the file doesn't exist, everything should be a no-op
+testKeyValueNoFile() {
+  # empty file argument
+  local empty=""
+
+  kv_set $empty key value
+
+  assertEquals "$(kv_get $empty key)" ""
+  assertEquals "$(kv_keys $empty)" ""
+  assertEquals "$(kv_list $empty)" ""
+
+  local store="/tmp/does-not-exist"
+
+  kv_set $store key value
+
+  assertEquals "" "$(kv_get $store key)"
+  assertEquals "" "$(kv_keys $store)"
+  assertEquals "" "$(kv_list $store)"
+
+  # running these commands has not created this file
+  assertTrue "[[ ! -e $store ]]"
+
+  local space=" "
+  kv_set $space key value
+
+  assertEquals "$(kv_get $space key)" ""
+  assertEquals "$(kv_keys $space)" ""
+  assertEquals "$(kv_list $space)" ""
+}
+
+# the modules to be tested
+source "$(pwd)"/lib/monitor.sh
+source "$(pwd)"/lib/output.sh
+source "$(pwd)"/lib/kvstore.sh
+
+# import the testing framework
+source "$(pwd)"/test/shunit2

test/utils

@@ -36,7 +36,7 @@ capture()
 
   LAST_COMMAND="$@"
 
-  $@ >${STD_OUT} 2>${STD_ERR}
+  "$@" >${STD_OUT} 2>${STD_ERR}
   RETURN=$?
   rtrn=${RETURN} # deprecated
 }
@@ -186,5 +186,26 @@ assertFileMD5()
     fail "no suitable MD5 hashing command found on this system"
   fi
 
-  assertEquals "${expected_md5_cmd_output}" "`${md5_cmd}`"
+  assertEquals "${expected_md5_cmd_output}" "$(${md5_cmd})"
+}
+
+assertDirectoryExists() {
+  if [[ ! -e "$1" ]]; then
+    fail "$1 does not exist"
+  fi
+  if [[ ! -d $1 ]]; then
+    fail "$1 is not a directory"
+  fi
+}
+
+assertFileExists()
+{
+  filename=$1
+  assertTrue "$filename doesn't exist" "[[ -e $filename ]]"
+}
+
+assertFileDoesNotExist()
+{
+  filename=$1
+  assertTrue "$filename exists" "[[ ! -e $filename ]]"
 }