Homebrew without sudo-Aub's fork with a few minor changes from kenchan's fork

install.rb

#!/System/Library/Frameworks/Ruby.framework/Versions/Current/usr/bin/ruby

# chmod +x install.rb
# ./install.rb

YOUR_HOME = ENV['HOME']
HOMEBREW_PREFIX = "#{YOUR_HOME}/usr/local"
system "mkdir -p #{HOMEBREW_PREFIX}"
HOMEBREW_CACHE = "#{YOUR_HOME}/Library/Caches/Homebrew"
HOMEBREW_REPO = 'https://github.com/Homebrew/brew'

module Tty extend self
  def blue; bold 34; end
  def white; bold 39; end
  def red; underline 31; end
  def reset; escape 0; end
  def bold n; escape "1;#{n}" end
  def underline n; escape "4;#{n}" end
  def escape n; "\033[#{n}m" if STDOUT.tty? end
end

class Array
  def shell_s
    cp = dup
    first = cp.shift
    cp.map{ |arg| arg.gsub " ", "\\ " }.unshift(first) * " "
  end
end

def ohai *args
  puts "#{Tty.blue}==>#{Tty.white} #{args.shell_s}#{Tty.reset}"
end

def warn warning
  puts "#{Tty.red}Warning#{Tty.reset}: #{warning.chomp}"
end

def system *args
  abort "Failed during: #{args.shell_s}" unless Kernel.system(*args)
end

def sudo *args
  #ohai "/usr/bin/sudo", *args
  #system "/usr/bin/sudo", *args
  system *args
end

def getc  # NOTE only tested on OS X
  system "/bin/stty raw -echo"
  if STDIN.respond_to?(:getbyte)
    STDIN.getbyte
  else
    STDIN.getc
  end
ensure
  system "/bin/stty -raw echo"
end

def wait_for_user
  puts
  puts "Press RETURN to continue or any other key to abort"
  c = getc
  # we test for \r and \n because some stuff does \r instead
  abort unless c == 13 or c == 10
end

module Version
  def <=>(other)
    split(".").map { |i| i.to_i } <=> other.split(".").map { |i| i.to_i }
  end
end

def macos_version
  @macos_version ||= `/usr/bin/sw_vers -productVersion`.chomp[/10\.\d+/].extend(Version)
end

def git
  @git ||= if ENV['GIT'] and File.executable? ENV['GIT']
    ENV['GIT']
  elsif Kernel.system '/usr/bin/which -s git'
    'git'
  else
    exe = `xcrun -find git 2>/dev/null`.chomp
    exe if $? && $?.success? && !exe.empty? && File.executable?(exe)
  end

  return unless @git
  # Github only supports HTTPS fetches on 1.7.10 or later:
  # https://help.github.com/articles/https-cloning-errors
  `#{@git} --version` =~ /git version (\d\.\d+\.\d+)/
  return if $1.nil? or $1.extend(Version) < "1.7.10"

  @git
end

def chmod?(d)
  File.directory?(d) && !(File.readable?(d) && File.writable?(d) && File.executable?(d))
end

def chgrp?(d)
  !File.grpowned?(d)
end

# Invalidate sudo timestamp before exiting
#at_exit { Kernel.system "/usr/bin/sudo", "-k" }

# The block form of Dir.chdir fails later if Dir.CWD doesn't exist which I
# guess is fair enough. Also sudo prints a warning message for no good reason
system "cd #{YOUR_HOME}/usr"

####################################################################### script
abort "See Linuxbrew: http://brew.sh/linuxbrew/" if /linux/i === RUBY_PLATFORM
abort "MacOS too old, see: https://github.com/mistydemeo/tigerbrew" if macos_version < "10.5"
abort "Don't run this as root!" if Process.uid == 0
#abort <<-EOABORT unless `groups`.split.include? "admin"
#This script requires the user #{ENV['USER']} to be an Administrator. If this
#sucks for you then you can install Homebrew in your home directory or however
#you please; please refer to our homepage. If you still want to use this script
#set your user to be an Administrator in System Preferences or `su' to a
#non-root user with Administrator privileges.
#EOABORT
abort <<-EOABORT unless Dir["#{HOMEBREW_PREFIX}/.git/*"].empty?
It appears Homebrew is already installed. If your intent is to reinstall you
should do the following before running this installer again:
    rm -rf #{HOMEBREW_PREFIX}/Cellar #{HOMEBREW_PREFIX}/.git && brew cleanup
EOABORT
# Tests will fail if the prefix exists, but we don't have execution
# permissions. Abort in this case.
abort <<-EOABORT if File.directory? HOMEBREW_PREFIX and not File.executable? HOMEBREW_PREFIX
The Homebrew prefix, #{HOMEBREW_PREFIX}, exists but is not searchable. If this is
not intentional, please restore the default permissions and try running the
installer again:
    sudo chmod 775 #{HOMEBREW_PREFIX}
EOABORT
abort <<-EOABORT if `/usr/bin/xcrun clang 2>&1` =~ /license/ && !$?.success?
You have not agreed to the Xcode license.
Before running the installer again please agree to the license by opening
Xcode.app or running:
    sudo xcodebuild -license
EOABORT

ohai "This script will install:"
puts "#{HOMEBREW_PREFIX}/bin/brew"
puts "#{HOMEBREW_PREFIX}/Library/..."
puts "#{HOMEBREW_PREFIX}/share/man/man1/brew.1"

chmods = %w( . bin etc include lib lib/pkgconfig Library sbin share var var/log share/locale share/man
             share/man/man1 share/man/man2 share/man/man3 share/man/man4
             share/man/man5 share/man/man6 share/man/man7 share/man/man8
             share/info share/doc share/aclocal ).
             map { |d| File.join(HOMEBREW_PREFIX, d) }.select { |d| chmod?(d) }
chgrps = chmods.select { |d| chgrp?(d) }

unless chmods.empty?
  ohai "The following directories will be made group writable:"
  puts(*chmods)
end
unless chgrps.empty?
  ohai "The following directories will have their group set to #{Tty.underline 39}admin#{Tty.reset}:"
  puts(*chgrps)
end

wait_for_user if STDIN.tty?

if File.directory? HOMEBREW_PREFIX
  sudo "/bin/chmod", "g+rwx", *chmods unless chmods.empty?
  ohai "/usr/bin/chgrp", "admin", *chgrps unless chgrps.empty?
  sudo "/usr/bin/chgrp", "admin", *chgrps unless chgrps.empty?
else
  sudo "/bin/mkdir", HOMEBREW_PREFIX
  sudo "/bin/chmod", "g+rwx", HOMEBREW_PREFIX
  # the group is set to wheel by default for some reason
  ohai "/usr/bin/chgrp", "admin", HOMEBREW_PREFIX
  sudo "/usr/bin/chgrp", "admin", HOMEBREW_PREFIX
end

sudo "/bin/mkdir", HOMEBREW_CACHE unless File.directory? HOMEBREW_CACHE
sudo "/bin/chmod", "g+rwx", HOMEBREW_CACHE if chmod? HOMEBREW_CACHE

if macos_version >= "10.9"
  developer_dir = `/usr/bin/xcode-select -print-path 2>/dev/null`.chomp
  if developer_dir.empty? || !File.exist?("#{developer_dir}/usr/bin/git")
    ohai "Installing the Command Line Tools (expect a GUI popup):"
    sudo "/usr/bin/xcode-select", "--install"
    puts "Press any key when the installation has completed."
    getc
  end
end

ohai "Downloading and installing Homebrew..."
Dir.chdir HOMEBREW_PREFIX do
  if git
    # we do it in four steps to avoid merge errors when reinstalling
    system git, "init", "-q"

    # "git remote add" will fail if the remote is defined in the global config
    system git, "config", "remote.origin.url", HOMEBREW_REPO
    system git, "config", "remote.origin.fetch", "+refs/heads/*:refs/remotes/origin/*"

    args = git, "fetch", "origin", "master:refs/remotes/origin/master", "-n"
    args << "--depth=1" if ARGV.include? "--fast"
    system(*args)

    system git, "reset", "--hard", "origin/master"
  else
    # -m to stop tar erroring out if it can't modify the mtime for root owned directories
    # pipefail to cause the exit status from curl to propogate if it fails
    # we use -k for curl because Leopard has a bunch of bad SSL certificates
    curl_flags = "fsSL"
    curl_flags << "k" if macos_version <= "10.5"
    system "/bin/bash -o pipefail -c '/usr/bin/curl -#{curl_flags} #{HOMEBREW_REPO}/tarball/master | /usr/bin/tar xz -m --strip 1'"
  end
end

warn "#{HOMEBREW_PREFIX}/bin is not in your PATH." unless ENV['PATH'].split(':').include? "#{HOMEBREW_PREFIX}/bin"

ohai "Installation successful!"
ohai "Next steps"

if macos_version < "10.9" and macos_version > "10.6"
  `/usr/bin/cc --version 2> /dev/null` =~ %r[clang-(\d{2,})]
  version = $1.to_i
  puts "Install the #{Tty.white}Command Line Tools for Xcode#{Tty.reset}: https://developer.apple.com/downloads" if version < 425
else
  puts "Install #{Tty.white}Xcode#{Tty.reset}: https://developer.apple.com/xcode" unless File.exist? "/usr/bin/cc"
end


puts "You must set `export PATH=#{HOMEBREW_PREFIX}/bin:$PATH` to your shell??"
puts "Run `brew update`??"
puts "Run `brew doctor` #{Tty.white}before#{Tty.reset} you install anything"
puts "Run `brew help` to get started"

(Updating my script with the final successful version)

BTW this was run on mojave in the latest iTerm (super basic shell through, no zsh stuff setup yet, of course, since I'd like to install zsh via homebrew)

I also recommend most people consider running some of the commands here to update to the latest openssl before running brew update for the first time: https://superuser.com/a/1338769/88226

brew install git is throwing a xcode-style popup to install "javac", you can click "more info" which goes to an adobe flash download page... or "ok" which does nothing. Terminal is getting stuck here

==> Installing dependencies for git: gettext and pcre2
==> Installing git dependency: gettext
==> ./configure --prefix=/Users/devinrhode3/usr/local/Cellar/gettext/0.21 --with-included-gettext gl_cv_func_
^C

Somehow, got everything updated. Git is latest version, etc. One thing: I couldn't change my default shell to the brew-installed one, would just say something like "can't change shell to non-standard shell". So, I ended up uninstalling zsh and using the default /bin/zsh in mojave, which is 5.3 instead of 5.8. All of my (oldish) zgen stuff works fine, with the latest zgen. Basically my terminal works as expected.

For homebrew cask users, you'll want to add this to your ~/.profile:

export HOMEBREW_CASK_OPTS="--appdir=~/Users/devinrhode3/Applications --fontdir=/Users/devinrhode3/Library/Fonts"

upgrading packages still works. brew update and brew upgrade <pkg>. Might need to turn off vpn if you got one of those

I'm on Catalina with zsh and I found a couple of things to get it to work.

 puts "You must set `exports PATH=#{HOMEBREW_PREFIX}/bin:$PATH` to your shell??"

Should be export

Then to edit your PATH in .zshrc so it works after using another tty instance or window is to use this path statement,

export PATH=$HOME/bin:$HOME/usr/local/bin:$PATH

The $HOME/usr/local/bin being the most important one.
The one you provided didn't work on my system and the default zsh one didn't work either. So after some messing around, I found $HOME/usr/local/bin to be the solution when you try to call it.

Otherwise fantastic script modifications to get it working

Thanks for the feedback @Neopect. I corrected exports to export. The rest I'll have to evaluate once I recover my shell profile code.

Running this on Monterey again...

Copied whole script as-is

./install.rb:113:in `<main>': undefined method `<' for nil:NilClass (NoMethodError)

Seems like that line checks if the macOS version is too old, and then recommends tigerbrew...

It's probably failing cause my version is newer than expected. So I'm removing that line (and replacing with newline, so line numbers stay the same).

=====

Ran again:

./install.rb       
==> This script will install:
/Users/devinrhode2/usr/local/bin/brew
/Users/devinrhode2/usr/local/Library/...
/Users/devinrhode2/usr/local/share/man/man1/brew.1

Press RETURN to continue or any other key to abort
./install.rb:180:in `<main>': undefined method `>=' for nil:NilClass (NoMethodError)

...

So now I think any version comparison for the macos_version is going to be buggy.

Ok... Giving this a try...

#!/System/Library/Frameworks/Ruby.framework/Versions/Current/usr/bin/ruby

# chmod +x install.rb
# ./install.rb

YOUR_HOME = ENV['HOME']
HOMEBREW_PREFIX = "#{YOUR_HOME}/usr/local"
system "mkdir -p #{HOMEBREW_PREFIX}"
HOMEBREW_CACHE = "#{YOUR_HOME}/Library/Caches/Homebrew"
HOMEBREW_REPO = 'https://github.com/Homebrew/brew'

module Tty extend self
  def blue; bold 34; end
  def white; bold 39; end
  def red; underline 31; end
  def reset; escape 0; end
  def bold n; escape "1;#{n}" end
  def underline n; escape "4;#{n}" end
  def escape n; "\033[#{n}m" if STDOUT.tty? end
end

class Array
  def shell_s
    cp = dup
    first = cp.shift
    cp.map{ |arg| arg.gsub " ", "\\ " }.unshift(first) * " "
  end
end

def ohai *args
  puts "#{Tty.blue}==>#{Tty.white} #{args.shell_s}#{Tty.reset}"
end

def warn warning
  puts "#{Tty.red}Warning#{Tty.reset}: #{warning.chomp}"
end

def system *args
  abort "Failed during: #{args.shell_s}" unless Kernel.system(*args)
end

def sudo *args
  #ohai "/usr/bin/sudo", *args
  #system "/usr/bin/sudo", *args
  system *args
end

def getc  # NOTE only tested on OS X
  system "/bin/stty raw -echo"
  if STDIN.respond_to?(:getbyte)
    STDIN.getbyte
  else
    STDIN.getc
  end
ensure
  system "/bin/stty -raw echo"
end

def wait_for_user
  puts
  puts "Press RETURN to continue or any other key to abort"
  c = getc
  # we test for \r and \n because some stuff does \r instead
  abort unless c == 13 or c == 10
end

module Version
  def <=>(other)
    split(".").map { |i| i.to_i } <=> other.split(".").map { |i| i.to_i }
  end
end

def macos_version
  @macos_version ||= `/usr/bin/sw_vers -productVersion`.chomp[/10\.\d+/].extend(Version)
end

def git
  @git ||= if ENV['GIT'] and File.executable? ENV['GIT']
    ENV['GIT']
  elsif Kernel.system '/usr/bin/which -s git'
    'git'
  else
    exe = `xcrun -find git 2>/dev/null`.chomp
    exe if $? && $?.success? && !exe.empty? && File.executable?(exe)
  end

  return unless @git
  # Github only supports HTTPS fetches on 1.7.10 or later:
  # https://help.github.com/articles/https-cloning-errors
  `#{@git} --version` =~ /git version (\d\.\d+\.\d+)/
  return if $1.nil? or $1.extend(Version) < "1.7.10"

  @git
end

def chmod?(d)
  File.directory?(d) && !(File.readable?(d) && File.writable?(d) && File.executable?(d))
end

def chgrp?(d)
  !File.grpowned?(d)
end

# Invalidate sudo timestamp before exiting
#at_exit { Kernel.system "/usr/bin/sudo", "-k" }

# The block form of Dir.chdir fails later if Dir.CWD doesn't exist which I
# guess is fair enough. Also sudo prints a warning message for no good reason
system "cd #{YOUR_HOME}/usr"

####################################################################### script
abort "See Linuxbrew: http://brew.sh/linuxbrew/" if /linux/i === RUBY_PLATFORM

abort "Don't run this as root!" if Process.uid == 0
#abort <<-EOABORT unless `groups`.split.include? "admin"
#This script requires the user #{ENV['USER']} to be an Administrator. If this
#sucks for you then you can install Homebrew in your home directory or however
#you please; please refer to our homepage. If you still want to use this script
#set your user to be an Administrator in System Preferences or `su' to a
#non-root user with Administrator privileges.
#EOABORT
abort <<-EOABORT unless Dir["#{HOMEBREW_PREFIX}/.git/*"].empty?
It appears Homebrew is already installed. If your intent is to reinstall you
should do the following before running this installer again:
    rm -rf #{HOMEBREW_PREFIX}/Cellar #{HOMEBREW_PREFIX}/.git && brew cleanup
EOABORT
# Tests will fail if the prefix exists, but we don't have execution
# permissions. Abort in this case.
abort <<-EOABORT if File.directory? HOMEBREW_PREFIX and not File.executable? HOMEBREW_PREFIX
The Homebrew prefix, #{HOMEBREW_PREFIX}, exists but is not searchable. If this is
not intentional, please restore the default permissions and try running the
installer again:
    sudo chmod 775 #{HOMEBREW_PREFIX}
EOABORT
abort <<-EOABORT if `/usr/bin/xcrun clang 2>&1` =~ /license/ && !$?.success?
You have not agreed to the Xcode license.
Before running the installer again please agree to the license by opening
Xcode.app or running:
    sudo xcodebuild -license
EOABORT

ohai "This script will install:"
puts "#{HOMEBREW_PREFIX}/bin/brew"
puts "#{HOMEBREW_PREFIX}/Library/..."
puts "#{HOMEBREW_PREFIX}/share/man/man1/brew.1"

chmods = %w( . bin etc include lib lib/pkgconfig Library sbin share var var/log share/locale share/man
             share/man/man1 share/man/man2 share/man/man3 share/man/man4
             share/man/man5 share/man/man6 share/man/man7 share/man/man8
             share/info share/doc share/aclocal ).
             map { |d| File.join(HOMEBREW_PREFIX, d) }.select { |d| chmod?(d) }
chgrps = chmods.select { |d| chgrp?(d) }

unless chmods.empty?
  ohai "The following directories will be made group writable:"
  puts(*chmods)
end
unless chgrps.empty?
  ohai "The following directories will have their group set to #{Tty.underline 39}admin#{Tty.reset}:"
  puts(*chgrps)
end

wait_for_user if STDIN.tty?

if File.directory? HOMEBREW_PREFIX
  sudo "/bin/chmod", "g+rwx", *chmods unless chmods.empty?
  ohai "/usr/bin/chgrp", "admin", *chgrps unless chgrps.empty?
  sudo "/usr/bin/chgrp", "admin", *chgrps unless chgrps.empty?
else
  sudo "/bin/mkdir", HOMEBREW_PREFIX
  sudo "/bin/chmod", "g+rwx", HOMEBREW_PREFIX
  # the group is set to wheel by default for some reason
  ohai "/usr/bin/chgrp", "admin", HOMEBREW_PREFIX
  sudo "/usr/bin/chgrp", "admin", HOMEBREW_PREFIX
end

sudo "/bin/mkdir", HOMEBREW_CACHE unless File.directory? HOMEBREW_CACHE
sudo "/bin/chmod", "g+rwx", HOMEBREW_CACHE if chmod? HOMEBREW_CACHE











ohai "Downloading and installing Homebrew..."
Dir.chdir HOMEBREW_PREFIX do
  if git
    # we do it in four steps to avoid merge errors when reinstalling
    system git, "init", "-q"

    # "git remote add" will fail if the remote is defined in the global config
    system git, "config", "remote.origin.url", HOMEBREW_REPO
    system git, "config", "remote.origin.fetch", "+refs/heads/*:refs/remotes/origin/*"

    args = git, "fetch", "origin", "master:refs/remotes/origin/master", "-n"
    args << "--depth=1" if ARGV.include? "--fast"
    system(*args)

    system git, "reset", "--hard", "origin/master"
  else
    # -m to stop tar erroring out if it can't modify the mtime for root owned directories
    # pipefail to cause the exit status from curl to propogate if it fails
    # we use -k for curl because Leopard has a bunch of bad SSL certificates
    curl_flags = "fsSL"

    system "/bin/bash -o pipefail -c '/usr/bin/curl -#{curl_flags} #{HOMEBREW_REPO}/tarball/master | /usr/bin/tar xz -m --strip 1'"
  end
end

warn "#{HOMEBREW_PREFIX}/bin is not in your PATH." unless ENV['PATH'].split(':').include? "#{HOMEBREW_PREFIX}/bin"

ohai "Installation successful!"
ohai "Next steps"












puts "You must set `exports PATH=#{HOMEBREW_PREFIX}/bin:$PATH` to your shell??"
puts "Run `brew update`??"
puts "Run `brew doctor` #{Tty.white}before#{Tty.reset} you install anything"
puts "Run `brew help` to get started"

The /usr/bin/cc file already exists on my machine, so deleted the last if/else chunk doing some comparisons...

FYI:

/usr/bin/sw_vers -productVersion
12.6.3

I manually installed XCode command line tools

Seems to have worked!

% ./install.rb                    
==> This script will install:
/Users/devinrhode2/usr/local/bin/brew
/Users/devinrhode2/usr/local/Library/...
/Users/devinrhode2/usr/local/share/man/man1/brew.1

Press RETURN to continue or any other key to abort
==> Downloading and installing Homebrew...
remote: Enumerating objects: 231128, done.
remote: Counting objects: 100% (576/576), done.
remote: Compressing objects: 100% (382/382), done.
remote: Total 231128 (delta 217), reused 480 (delta 171), pack-reused 230552
Receiving objects: 100% (231128/231128), 66.39 MiB | 44.00 MiB/s, done.
Resolving deltas: 100% (169751/169751), done.
From https://github.com/Homebrew/brew
 * [new branch]          master     -> origin/master
HEAD is now at 3e2c713c9 Merge pull request #14870 from nandahkrishna/fix-requirement
Warning: /Users/devinrhode2/usr/local/bin is not in your PATH.
==> Installation successful!
==> Next steps
You must set `exports PATH=/Users/devinrhode2/usr/local/bin:$PATH` to your shell??
Run `brew update`??
Run `brew doctor` before you install anything
Run `brew help` to get started
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