/usr/local/Homebrew/Library/Homebrew/version.rb:368:in initialize': Version value must be a string; got a NilClass () (TypeError) from /usr/local/Homebrew/Library/Homebrew/os/mac/version.rb:26:ininitialize'
from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:in new' from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:inversion'
from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:58:in prerelease?' from /usr/local/Homebrew/Library/Homebrew/os.rb:21:in'
from /usr/local/Homebrew/Library/Homebrew/os.rb:3:in <top (required)>' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:inrequire'
from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in require' from /usr/local/Homebrew/Library/Homebrew/global.rb:37:in<top (required)>'
from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:in require_relative' from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:in'
/usr/local/Homebrew/Library/Homebrew/version.rb:368:in'
from /usr/local/Homebrew/Library/Homebrew/os.rb:3:in '
initialize': Version value must be a string; got a NilClass () (TypeError) from /usr/local/Homebrew/Library/Homebrew/os/mac/version.rb:26:in
initialize' from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:innew' from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:24:in
version' from /usr/local/Homebrew/Library/Homebrew/os/mac.rb:58:inprerelease?' from /usr/local/Homebrew/Library/Homebrew/os.rb:21:in
<top (required)>' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in
require' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:inrequire' from /usr/local/Homebrew/Library/Homebrew/global.rb:37:in
<top (required)>' from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:inrequire_relative' from /usr/local/Homebrew/Library/Homebrew/brew.rb:23:in