before_install_linux.sh in rmagick-4.1.0.rc2 vs before_install_linux.sh in rmagick-4.1.0

@@ -1,5 +1,7 @@
+#!/usr/bin/env bash
+
 set -euox pipefail
 
 gem install bundler
 
 if [ -v STYLE_CHECKS ]; then
@@ -11,69 +13,57 @@
   echo "you must specify an ImageMagick version."
   echo "example: 'IMAGEMAGICK_VERSION=6.8.9-10 bash ./before_install_linux.sh'"
   exit 1
 fi
 
+sudo apt-get clean
+sudo apt-get update
+
 # remove all existing imagemagick related packages
 sudo apt-get autoremove -y imagemagick* libmagick* --purge
 
-if [ ! -v TRAVIS ]; then
-  sudo apt-get update
+# install build tools, ImageMagick delegates
+sudo apt-get install -y build-essential libx11-dev libxext-dev zlib1g-dev \
+  liblcms2-dev libpng-dev libjpeg-dev libfreetype6-dev libxml2-dev \
+  libtiff5-dev libwebp-dev vim gsfonts ghostscript ccache
 
-  # install build tools, ImageMagick delegates
-  sudo apt-get install -y build-essential libx11-dev libxext-dev zlib1g-dev \
-    liblcms2-dev libpng-dev libjpeg-dev libfreetype6-dev libxml2-dev \
-    libtiff5-dev libwebp-dev vim ghostscript ccache
-fi
-
 if [ ! -d /usr/include/freetype ]; then
   # If `/usr/include/freetype` is not existed, ImageMagick 6.7 configuration fails about Freetype.
   sudo ln -sf /usr/include/freetype2 /usr/include/freetype
 fi
 
-project_dir=`pwd`
-build_dir=${project_dir}/build-ImageMagick/ImageMagick-${IMAGEMAGICK_VERSION}
+project_dir=$(pwd)
+build_dir="${project_dir}/build-ImageMagick/ImageMagick-${IMAGEMAGICK_VERSION}"
 if [ -v CONFIGURE_OPTIONS ]; then
-  build_dir=${build_dir}-${CONFIGURE_OPTIONS}
+  build_dir="${build_dir}-${CONFIGURE_OPTIONS}"
 fi
 
 build_imagemagick() {
   mkdir -p build-ImageMagick
 
   version=(${IMAGEMAGICK_VERSION//./ })
-  if (( "${version[0]}" >= 7 )); then
-    wget https://github.com/ImageMagick/ImageMagick/archive/${IMAGEMAGICK_VERSION}.tar.gz
-    tar -xf ${IMAGEMAGICK_VERSION}.tar.gz
-    mv ImageMagick-${IMAGEMAGICK_VERSION} $build_dir
-  elif (( "${version[0]}${version[1]}" >= 69 )); then
-    wget https://github.com/ImageMagick/ImageMagick6/archive/${IMAGEMAGICK_VERSION}.tar.gz
-    tar -xf ${IMAGEMAGICK_VERSION}.tar.gz
-    rm ${IMAGEMAGICK_VERSION}.tar.gz
-    mv ImageMagick6-${IMAGEMAGICK_VERSION} $build_dir
-  else
-    wget https://www.imagemagick.org/download/releases/ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz
-    tar -xf ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz
-    rm ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz
-    mv ImageMagick-${IMAGEMAGICK_VERSION} $build_dir
-  fi
+  wget "https://imagemagick.org/download/releases/ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz"
+  tar -xf "ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz"
+  rm "ImageMagick-${IMAGEMAGICK_VERSION}.tar.xz"
+  mv "ImageMagick-${IMAGEMAGICK_VERSION}" "${build_dir}"
 
   options="--with-magick-plus-plus=no --disable-docs"
   if [ -v CONFIGURE_OPTIONS ]; then
-    options="${CONFIGURE_OPTIONS} $options"
+    options="${CONFIGURE_OPTIONS} ${options}"
   fi
 
-  cd $build_dir
-  CC="ccache cc" CXX="ccache c++" ./configure --prefix=/usr $options
+  cd "${build_dir}"
+  CC="ccache cc" CXX="ccache c++" ./configure --prefix=/usr "${options}"
   make -j
 }
 
-if [ ! -d $build_dir ]; then
+if [ ! -d "${build_dir}" ]; then
   build_imagemagick
 fi
 
-cd $build_dir
+cd "${build_dir}"
 sudo make install -j
-cd $project_dir
+cd "${project_dir}"
 
 sudo ldconfig
 
 set +ux