executable_download-nvim-dev

#!/usr/bin/env bash

# dependencies: wget, curl, tar, grep

# variables and constants
readonly DOWNLOAD_DIRECTORY=$HOME/.cache/neovim-prerelease
readonly DOWNLOADED_ARCHIVE=$DOWNLOAD_DIRECTORY/nvim-linux64.tar.gz
readonly EXTRACTED_ARCHIVE=$DOWNLOAD_DIRECTORY/nvim-linux64
readonly CHECKSUM=$DOWNLOAD_DIRECTORY/nvim-linux64.tar.gz.sha256sum
readonly EXECUTABLE=$DOWNLOAD_DIRECTORY/nvim-linux64/bin/nvim
readonly local_version=`$EXECUTABLE --version | head -n 1`
readonly latest_version=`curl --location https://github.com/neovim/neovim/releases/tag/nightly | grep "NVIM v.*" --only-matching | head -n 1`

# compare
echo -e "local version : $local_version"
echo -e "latest version: $latest_version"
if [ "$local_version" = "$latest_version" ];then
  echo "Local version is up-to-date."
  exit
else
  read -p "Continue to download latest version? [Y,n]" answer
  if [ "${answer,,}" == "n" ]; then
    exit
  fi
fi

# download
if [ ! -d $DOWNLOAD_DIRECTORY ]; then
  mkdir --parents $DOWNLOAD_DIRECTORY
fi
wget https://github.com/neovim/neovim/releases/download/nightly/nvim-linux64.tar.gz \
  https://github.com/neovim/neovim/releases/download/nightly/nvim-linux64.tar.gz.sha256sum \
  --directory-prefix=$DOWNLOAD_DIRECTORY
cd $DOWNLOAD_DIRECTORY
sha256sum --check $CHECKSUM || exit
rm -r $EXTRACTED_ARCHIVE && echo "deleted old $EXTRACTED_ARCHIVE"
tar xzf $DOWNLOADED_ARCHIVE --directory=$DOWNLOAD_DIRECTORY
rm -r $DOWNLOADED_ARCHIVE $CHECKSUM
readonly current_version=`$EXECUTABLE --version | head -n 3`
echo -e "\nprevious version:\n$local_version"
echo -e "\ncurrent versoin:\n$current_version"
echo -e "\nNeovim prerelease is downloaded to $DOWNLOAD_DIRECTORY"
echo -e "\nExecutable is located at $EXECUTABLE"
echo -e "\nYou can make add alias to your shell config such as .bashrc and .zshrc"
echo -e "\nalias nnv=$EXECUTABLE"