Add rest of lib/* to shellcheck (#609)

* Add rest of lib/* to shellcheck

lib/kvstore.sh

+#!/usr/bin/env bash
 
 kv_create() {
   local f=$1
-  mkdir -p $(dirname $f)
-  touch $f
+  mkdir -p "$(dirname "$f")"
+  touch "$f"
 }
 
 kv_clear() {
   local f=$1
-  echo "" > $f
+  echo "" > "$f"
 }
 
 kv_set() {
   if [[ $# -eq 3 ]]; then
     local f=$1
     if [[ -f $f ]]; then
-      echo "$2=$3" >> $f
+      echo "$2=$3" >> "$f"
     fi
   fi
 }
 
-# get the value, but don't unwrap quotes
 kv_get() {
   if [[ $# -eq 2 ]]; then
     local f=$1
     if [[ -f $f ]]; then
-      grep "^$2=" $f | sed -e "s/^$2=//" | tail -n 1
+      grep "^$2=" "$f" | sed -e "s/^$2=//" | tail -n 1
     fi
   fi
 }
 
+# get the value, but wrap it in quotes if it contains a space
 kv_get_escaped() {
-  local value=$(kv_get $1 $2 $3)
+  local value
+  value=$(kv_get "$1" "$2")
   if [[ $value =~ [[:space:]]+ ]]; then
     echo "\"$value\""
   else
-    echo $value
+    echo "$value"
   fi
 }
 
@@ -46,7 +48,7 @@ kv_keys() {
     # get list of keys
     while IFS="=" read -r key value; do
       keys+=("$key")
-    done < $f
+    done < "$f"
 
     echo "${keys[@]}" | tr ' ' '\n' | sort -u
   fi
@@ -55,9 +57,9 @@ kv_keys() {
 kv_list() {
   local f=$1
 
-  kv_keys $f | tr ' ' '\n' | while read -r key; do
+  kv_keys "$f" | tr ' ' '\n' | while read -r key; do
     if [[ -n $key ]]; then
-      echo "$key=$(kv_get_escaped $f $key)"
+      echo "$key=$(kv_get_escaped "$f" "$key")"
     fi
   done
 }

lib/monitor.sh

+#!/usr/bin/env bash
 
 monitor_memory_usage() {
   local output_file="$1"
@@ -12,7 +13,7 @@ monitor_memory_usage() {
   pid=$!
 
   # if this build process is SIGTERM'd
-  trap "kill -TERM $pid" TERM
+  trap 'kill -TERM $pid' TERM
 
   # set the peak memory usage to 0 to start
   peak="0"
@@ -29,7 +30,7 @@ monitor_memory_usage() {
   done
 
   # ps gives us kb, let's convert to mb for convenience
-  echo "$(($peak / 1024))" > $output_file
+  echo "$((peak / 1024))" > "$output_file"
 
   # After wait returns we can get the exit code of $command
   wait $pid
@@ -43,16 +44,18 @@ monitor_memory_usage() {
 }
 
 monitor() {
+  local peak_mem_output start
   local command_name=$1
   shift
 
   local command=( "$@" )
-  local peak_mem_output=$(mktemp)
-  local start=$(nowms)
+
+  peak_mem_output=$(mktemp)
+  start=$(nowms)
 
   # execute the subcommand and save the peak memory usage
-  monitor_memory_usage $peak_mem_output "${command[@]}"
+  monitor_memory_usage "$peak_mem_output" "${command[@]}"
 
   mtime "exec.$command_name.time" "${start}"
-  mmeasure "exec.$command_name.memory" "$(cat $peak_mem_output)"
+  mmeasure "exec.$command_name.memory" "$(cat "$peak_mem_output")"
 }

lib/output.sh

+#!/usr/bin/env bash
+
 # TODO: Merge these with the output helpers in buildpack-stdlib:
 # https://github.com/heroku/buildpack-stdlib
 

lib/plugin.sh

+#!/usr/bin/env bash
 
 get_node_major_version() {
-  local node_version="$(node --version)"
+  local node_version
+
+  node_version="$(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 $major
+  echo "$major"
 }
 
 install_plugin() {
+  local major
   local bp_dir="$1"
   local build_dir="$2"
-  local major=$(get_node_major_version)
+  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
@@ -19,6 +23,6 @@ install_plugin() {
   # 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/"
+    tar -xzf "${plugin}" -C "${build_dir}/.heroku/"
   fi
 }

makefile

@@ -2,8 +2,7 @@ test: heroku-18 heroku-16 cedar-14
 
 shellcheck:
 	@shellcheck -x bin/compile bin/detect bin/release bin/test bin/test-compile
-	@shellcheck -x lib/binaries.sh lib/build-data.sh lib/cache.sh lib/dependencies.sh lib/environment.sh lib/json.sh lib/failure.sh
-	@echo TODO shellcheck -x lib/**/*.sh 
+	@shellcheck -x lib/**
 	@echo TODO shellcheck -x ci-profile/**/*.sh
 	@echo TODO shellcheck -x etc/**/*.sh