Change to use sh instead of bash (#206)

* Change to use sh instead of bash

Ensure POSIX compatibility

Author: deiga

install-binary.sh

@@ -1,23 +1,27 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 
 # Shamelessly copied from https://github.com/technosophos/helm-template
 
 PROJECT_NAME="helm-diff"
 PROJECT_GH="databus23/$PROJECT_NAME"
-GREP_COLOR="never"
+export GREP_COLOR="never"
 
-: ${HELM_PLUGIN_DIR:="$(helm home --debug=false)/plugins/helm-diff"}
+HELM_MAJOR_VERSION=$(helm version --client --short | awk -F '.' '{print $1}')
+
+if [ "$HELM_MAJOR_VERSION" = "Client: v2" ]; then
+  : ${HELM_PLUGIN_DIR:="$(helm home --debug=false)/plugins/helm-diff"}
+fi
 
 # Convert the HELM_PLUGIN_DIR to unix if cygpath is
 # available. This is the case when using MSYS2 or Cygwin
 # on Windows where helm returns a Windows path but we
 # need a Unix path
 
-if type cygpath > /dev/null 2>&1; then
+if type cygpath >/dev/null 2>&1; then
   HELM_PLUGIN_DIR=$(cygpath -u $HELM_PLUGIN_DIR)
 fi
 
-if [[ $SKIP_BIN_INSTALL == "1" ]]; then
+if [ "$SKIP_BIN_INSTALL" = "1" ]; then
   echo "Skipping binary install"
   exit
 fi
@@ -26,56 +30,56 @@ fi
 initArch() {
   ARCH=$(uname -m)
   case $ARCH in
-    armv5*) ARCH="armv5";;
-    armv6*) ARCH="armv6";;
-    armv7*) ARCH="armv7";;
-    aarch64) ARCH="arm64";;
-    x86) ARCH="386";;
-    x86_64) ARCH="amd64";;
-    i686) ARCH="386";;
-    i386) ARCH="386";;
+  armv5*) ARCH="armv5" ;;
+  armv6*) ARCH="armv6" ;;
+  armv7*) ARCH="armv7" ;;
+  aarch64) ARCH="arm64" ;;
+  x86) ARCH="386" ;;
+  x86_64) ARCH="amd64" ;;
+  i686) ARCH="386" ;;
+  i386) ARCH="386" ;;
   esac
 }
 
 # initOS discovers the operating system for this system.
 initOS() {
-  OS=$(echo `uname`|tr '[:upper:]' '[:lower:]')
+  OS=$(uname | tr '[:upper:]' '[:lower:]')
 
   case "$OS" in
-    # Msys support
-    msys*) OS='windows';;
-    # Minimalist GNU for Windows
-    mingw*) OS='windows';;
-    darwin) OS='macos';;
+  # Msys support
+  msys*) OS='windows' ;;
+  # Minimalist GNU for Windows
+  mingw*) OS='windows' ;;
+  darwin) OS='macos' ;;
   esac
 }
 
 # verifySupported checks that the os/arch combination is supported for
 # binary builds.
 verifySupported() {
-  local supported="linux-amd64\nfreebsd-amd64\nmacos-amd64\nwindows-amd64"
+  supported="linux-amd64\nfreebsd-amd64\nmacos-amd64\nwindows-amd64"
   if ! echo "${supported}" | grep -q "${OS}-${ARCH}"; then
     echo "No prebuild binary for ${OS}-${ARCH}."
     exit 1
   fi
 
-  if ! type "curl" > /dev/null && ! type "wget" > /dev/null; then
+  if ! type "curl" >/dev/null && ! type "wget" >/dev/null; then
     echo "Either curl or wget is required"
     exit 1
   fi
 }
 
 # getDownloadURL checks the latest available version.
 getDownloadURL() {
-  local version=$(git -C $HELM_PLUGIN_DIR describe --tags --exact-match 2>/dev/null)
+  version=$(git -C "$HELM_PLUGIN_DIR" describe --tags --exact-match 2>/dev/null)
   if [ -n "$version" ]; then
     DOWNLOAD_URL="https://github.com/$PROJECT_GH/releases/download/$version/helm-diff-$OS.tgz"
   else
     # Use the GitHub API to find the download url for this project.
-    local url="https://api.github.com/repos/$PROJECT_GH/releases/latest"
-    if type "curl" > /dev/null; then
+    url="https://api.github.com/repos/$PROJECT_GH/releases/latest"
+    if type "curl" >/dev/null; then
       DOWNLOAD_URL=$(curl -s $url | grep $OS | awk '/\"browser_download_url\":/{gsub( /[,\"]/,"", $2); print $2}')
-    elif type "wget" > /dev/null; then
+    elif type "wget" >/dev/null; then
       DOWNLOAD_URL=$(wget -q -O - $url | grep $OS | awk '/\"browser_download_url\":/{gsub( /[,\"]/,"", $2); print $2}')
     fi
   fi
@@ -86,9 +90,9 @@ getDownloadURL() {
 downloadFile() {
   PLUGIN_TMP_FILE="/tmp/${PROJECT_NAME}.tgz"
   echo "Downloading $DOWNLOAD_URL"
-  if type "curl" > /dev/null; then
+  if type "curl" >/dev/null; then
     curl -L "$DOWNLOAD_URL" -o "$PLUGIN_TMP_FILE"
-  elif type "wget" > /dev/null; then
+  elif type "wget" >/dev/null; then
     wget -q -O "$PLUGIN_TMP_FILE" "$DOWNLOAD_URL"
   fi
 }
@@ -110,7 +114,7 @@ fail_trap() {
   result=$?
   if [ "$result" != "0" ]; then
     echo "Failed to install $PROJECT_NAME"
-    echo "\tFor support, go to https://github.com/databus23/helm-diff."
+    printf '\tFor support, go to https://github.com/databus23/helm-diff.\n'
   fi
   exit $result
 }