Faster and more legible `brew doctor`

Please check for regressions. I was careful, but there was a lot of stuff.

Closes Homebrew/homebrew#9409.

1 files changed, 168 insertions, 289 deletions

diff --git a/Library/Homebrew/cmd/doctor.rb b/Library/Homebrew/cmd/doctor.rb
index afe306ecc..b192b72a4 100644
--- a/Library/Homebrew/cmd/doctor.rb
+++ b/Library/Homebrew/cmd/doctor.rb
@@ -1,5 +1,3 @@
-require 'stringio'
-
 class Volumes
   def initialize
     @volumes = []
@@ -25,6 +23,9 @@ class Volumes
 end
 
 
+class Checks
+  # Sorry for the lack of an indent here, the diff would have been unreadable.
+
 def remove_trailing_slash s
   (s[s.length-1] == '/') ? s[0,s.length-1] : s
 end
@@ -40,11 +41,10 @@ end
 def check_for_macgpg2
   if File.exist? "/Applications/start-gpg-agent.app" or
      File.exist? "/Library/Receipts/libiconv1.pkg"
-    puts <<-EOS.undent
-      If you have installed MacGPG2 via the package installer, several other
-      checks in this script will turn up problems, such as stray .dylibs in
-      /usr/local and permissions issues with share and man in /usr/local/.
-
+    <<-EOS.undent
+      You may have installed MacGPG2 via the package installer.
+      Several other checks in this script will turn up problems, such as stray
+      dylibs in /usr/local and permissions issues with share and man in /usr/local/.
     EOS
   end
 end
@@ -62,32 +62,30 @@ def check_for_stray_dylibs
   bad_dylibs = unbrewed_dylibs.reject {|d| white_list.key? File.basename(d) }
   return if bad_dylibs.empty?
 
-  puts <<-EOS.undent
+  s = <<-EOS.undent
     Unbrewed dylibs were found in /usr/local/lib.
-
     If you didn't put them there on purpose they could cause problems when
     building Homebrew formulae, and may need to be deleted.
 
     Unexpected dylibs:
   EOS
-  puts *bad_dylibs.collect { |f| "    #{f}" }
-  puts
+  bad_dylibs.each { |f| s << "    #{f}" }
+  s
 end
 
 def check_for_stray_static_libs
   unbrewed_alibs = Dir['/usr/local/lib/*.a'].select { |f| File.file? f and not File.symlink? f }
   return if unbrewed_alibs.empty?
 
-  puts <<-EOS.undent
+  s = <<-EOS.undent
     Unbrewed static libraries were found in /usr/local/lib.
-
     If you didn't put them there on purpose they could cause problems when
     building Homebrew formulae, and may need to be deleted.
 
     Unexpected static libraries:
   EOS
-  puts *unbrewed_alibs.collect { |f| "    #{f}" }
-  puts
+  unbrewed_alibs.each{ |f| s << "    #{f}" }
+  s
 end
 
 def check_for_stray_pcs
@@ -102,16 +100,15 @@ def check_for_stray_pcs
   bad_pcs = unbrewed_pcs.reject {|d| white_list.key? File.basename(d) }
   return if bad_pcs.empty?
 
-  puts <<-EOS.undent
+  s = <<-EOS.undent
     Unbrewed .pc files were found in /usr/local/lib/pkgconfig.
-
     If you didn't put them there on purpose they could cause problems when
     building Homebrew formulae, and may need to be deleted.
 
     Unexpected .pc files:
   EOS
-  puts *bad_pcs.collect { |f| "    #{f}" }
-  puts
+  bad_pcs.each{ |f| s << "    #{f}" }
+  s
 end
 
 def check_for_stray_las
@@ -125,101 +122,85 @@ def check_for_stray_las
   bad_las = unbrewed_las.reject {|d| white_list.key? File.basename(d) }
   return if bad_las.empty?
 
-  puts <<-EOS.undent
+  s = <<-EOS.undent
     Unbrewed .la files were found in /usr/local/lib.
-
     If you didn't put them there on purpose they could cause problems when
     building Homebrew formulae, and may need to be deleted.
 
     Unexpected .la files:
   EOS
-  puts *bad_las.collect { |f| "    #{f}" }
-  puts
+  bad_las.each{ |f| s << "    #{f}" }
+  s
 end
 
 def check_for_x11
   unless x11_installed?
-    puts <<-EOS.undent
+    <<-EOS.undent
       X11 not installed.
-
       You don't have X11 installed as part of your OS X installation.
-      This isn't required for all formulae, but is expected by some.
-
+      This is not required for all formulae, but is expected by some.
     EOS
   end
 end
 
 def check_for_nonstandard_x11
-  return unless File.exists? '/usr/X11'
   x11 = Pathname.new('/usr/X11')
   if x11.symlink?
-    puts <<-EOS.undent
-      "/usr/X11" was found, but it is a symlink to:
-        #{x11.resolved_path}
-
+    <<-EOS.undent
+      /usr/X11 is a symlink
       Homebrew's X11 support has only be tested with Apple's X11.
       In particular, "XQuartz" and "XDarwin" are not known to be compatible.
-
     EOS
   end
 end
 
 def check_for_other_package_managers
   if macports_or_fink_installed?
-    puts <<-EOS.undent
-      You have Macports or Fink installed. This can cause trouble.
-      You don't have to uninstall them, but you may like to try temporarily
-      moving them away, eg.
+    <<-EOS.undent
+      You have Macports or Fink installed.
+      This can cause trouble. You don't have to uninstall them, but you may like to
+      try temporarily moving them away, eg.
 
         sudo mv /opt/local ~/macports
-
     EOS
   end
 end
 
-def check_gcc_versions
-  gcc_42 = MacOS.gcc_42_build_version
-  gcc_40 = MacOS.gcc_40_build_version
-
-  if gcc_42 == nil
+def check_gcc_42
+  if MacOS.gcc_42_build_version == nil
     # Don't show this warning on Xcode 4.2+
     if MacOS.xcode_version < "4.2"
-      puts <<-EOS.undent
-        We couldn't detect gcc 4.2.x. Some formulae require this compiler.
-
-      EOS
+      "We couldn't detect gcc 4.2.x. Some formulae require this compiler."
     end
-  elsif gcc_42 < RECOMMENDED_GCC_42
-    puts <<-EOS.undent
-      Your gcc 4.2.x version is older than the recommended version. It may be advisable
-      to upgrade to the latest release of Xcode.
-
+  elsif MacOS.gcc_42_build_version < RECOMMENDED_GCC_42
+    <<-EOS.undent
+      Your gcc 4.2.x version is older than the recommended version.
+      It may be advisable to upgrade to the latest release of Xcode.
     EOS
   end
+end
 
+def check_xcode_exists
   if MacOS.xcode_version == nil
-      puts <<-EOS.undent
+      <<-EOS.undent
         We couldn't detect any version of Xcode.
         If you downloaded Xcode from the App Store, you may need to run the installer.
-
       EOS
   elsif MacOS.xcode_version < "4.0"
-    if gcc_40 == nil
-      puts <<-EOS.undent
-        We couldn't detect gcc 4.0.x. Some formulae require this compiler.
-
-      EOS
-    elsif gcc_40 < RECOMMENDED_GCC_40
-      puts <<-EOS.undent
-        Your gcc 4.0.x version is older than the recommended version. It may be advisable
-        to upgrade to the latest release of Xcode.
-
+    if MacOS.gcc_40_build_version == nil
+      "We couldn't detect gcc 4.0.x. Some formulae require this compiler."
+    elsif MacOS.gcc_40_build_version < RECOMMENDED_GCC_40
+      <<-EOS.undent
+        Your gcc 4.0.x version is older than the recommended version.
+        It may be advisable to upgrade to the latest release of Xcode.
       EOS
     end
   end
+end
 
+def check_cc
   unless File.exist? '/usr/bin/cc'
-    puts <<-EOS.undent
+    <<-EOS.undent
       You have no /usr/bin/cc.
       This means you probably can't build *anything*. You need to install the CLI
       Tools for Xcode. You can either download this from http://connect.apple.com/
@@ -241,8 +222,8 @@ def __check_subdir_access base
   end
 
   cant_read.sort!
-  if cant_read.length > 0
-    puts <<-EOS.undent
+  if cant_read.length > 0 then
+    s = <<-EOS.undent
     Some directories in #{target} aren't writable.
     This can happen if you "sudo make install" software that isn't managed
     by Homebrew. If a brew tries to add locale information to one of these
@@ -250,25 +231,22 @@ def __check_subdir_access base
     You should probably `chown` them:
 
     EOS
-    puts *cant_read.collect { |f| "    #{f}" }
-    puts
+    cant_read.each{ |f| s << "    #{f}\n" }
+    s
   end
 end
 
 def check_access_usr_local
   return unless HOMEBREW_PREFIX.to_s == '/usr/local'
 
-  unless Pathname('/usr/local').writable?
-    puts <<-EOS.undent
+  unless Pathname('/usr/local').writable? then <<-EOS.undent
     The /usr/local directory is not writable.
-
     Even if this folder was writable when you installed Homebrew, other
     software may change permissions on this folder. Some versions of the
     "InstantOn" component of Airfoil are known to do this.
 
     You should probably change the ownership and permissions of /usr/local
     back to your user account.
-
     EOS
   end
 end
@@ -283,10 +261,8 @@ end
 
 def __check_folder_access base, msg
   folder = HOMEBREW_PREFIX+base
-  return unless folder.exist?
-
-  unless folder.writable?
-    puts <<-EOS.undent
+  if folder.exist? and not folder.writable?
+    <<-EOS.undent
       #{folder} isn't writable.
       This can happen if you "sudo make install" software that isn't managed
       by Homebrew.
@@ -294,7 +270,6 @@ def __check_folder_access base, msg
       #{msg}
 
       You should probably `chown` #{folder}
-
     EOS
   end
 end
@@ -325,21 +300,20 @@ end
 
 def check_usr_bin_ruby
   if /^1\.9/.match RUBY_VERSION
-    puts <<-EOS.undent
+    <<-EOS.undent
       Ruby version #{RUBY_VERSION} is unsupported.
       Homebrew is developed and tested on Ruby 1.8.x, and may not work correctly
-      on Ruby 1.9.x. Patches are accepted as long as they don't break on 1.8.x.
-
+      on other Rubies. Patches are accepted as long as they don't break on 1.8.x.
     EOS
   end
 end
 
 def check_homebrew_prefix
   unless HOMEBREW_PREFIX.to_s == '/usr/local'
-    puts <<-EOS.undent
+    <<-EOS.undent
+      Your Homebrew is not installed to /usr/local
       You can install Homebrew anywhere you want, but some brews may only build
-      correctly if you install to /usr/local.
-
+      correctly if you install in /usr/local. Sorry!
     EOS
   end
 end
@@ -348,10 +322,9 @@ def check_xcode_prefix
   prefix = MacOS.xcode_prefix
   return if prefix.nil?
   if prefix.to_s.match(' ')
-    puts <<-EOS.undent
+    <<-EOS.undent
       Xcode is installed to a directory with a space in the name.
-      This may cause some formulae, such as libiconv, to fail to build.
-
+      This will cause some formulae, such as libiconv, to fail to build.
     EOS
   end
 end
@@ -360,8 +333,8 @@ def check_xcode_select_path
   path = `xcode-select -print-path 2>/dev/null`.chomp
   unless File.directory? path and File.file? "#{path}/usr/bin/xcodebuild"
     # won't guess at the path they should use because it's too hard to get right
-    ohai "Your Xcode is configured with an invalid path."
-    puts <<-EOS.undent
+    <<-EOS.undent
+      Your Xcode is configured with an invalid path.
       You should change it to the correct path. Please note that there is no correct
       path at this time if you have *only* installed the Command Line Tools for Xcode.
       If your Xcode is pre-4.3 or you installed the whole of Xcode 4.3 then one of
@@ -369,20 +342,21 @@ def check_xcode_select_path
 
           sudo xcode-select -switch /Developer
           sudo xcode-select -switch /Application/Xcode.app
-
     EOS
   end
 end
 
-def check_user_path
-  seen_prefix_bin = false
-  seen_prefix_sbin = false
+def check_user_path_1
+  $seen_prefix_bin = false
+  $seen_prefix_sbin = false
   seen_usr_bin = false
 
+  out = nil
+
   path_folders.each do |p| case p
     when '/usr/bin'
       seen_usr_bin = true
-      unless seen_prefix_bin
+      unless $seen_prefix_bin
         # only show the doctor message if there are any conflicts
         # rationale: a default install should not trigger any brew doctor messages
         conflicts = Dir["#{HOMEBREW_PREFIX}/bin/*"].
@@ -390,51 +364,47 @@ def check_user_path
             select{ |bn| File.exist? "/usr/bin/#{bn}" }
 
         if conflicts.size
-          ohai "/usr/bin occurs before #{HOMEBREW_PREFIX}/bin"
-          puts <<-EOS.undent
+          out = <<-EOS.undent
+            /usr/bin occurs before #{HOMEBREW_PREFIX}/bin
             This means that system-provided programs will be used instead of those
             provided by Homebrew. The following tools exist at both paths:
 
                 #{conflicts * "\n                "}
 
-            Consider editing your .bashrc to put #{HOMEBREW_PREFIX}/bin
-            ahead of /usr/bin in your PATH.
-
+            Consider ammending your PATH so that #{HOMEBREW_PREFIX}/bin
+            is ahead of /usr/bin in your PATH.
           EOS
         end
       end
     when "#{HOMEBREW_PREFIX}/bin"
-      seen_prefix_bin = true
+      $seen_prefix_bin = true
     when "#{HOMEBREW_PREFIX}/sbin"
-      seen_prefix_sbin = true
+      $seen_prefix_sbin = true
     end
   end
+  out
+end
 
-  unless seen_prefix_bin
-    puts <<-EOS.undent
-      Homebrew's bin was not found in your path. Some brews depend
-      on other brews that install tools to bin.
-
-      You should edit your .bashrc to add:
+def check_user_path_2
+  unless $seen_prefix_bin
+    <<-EOS.undent
+      Homebrew's bin was not found in your path.
+      Consider ammending your PATH variable so it contains:
         #{HOMEBREW_PREFIX}/bin
-      to the PATH variable.
-
-      EOS
+    EOS
   end
+end
 
+def check_user_path_3
   # Don't complain about sbin not being in the path if it doesn't exist
   sbin = (HOMEBREW_PREFIX+'sbin')
   if sbin.directory? and sbin.children.length > 0
-    unless seen_prefix_sbin
-      puts <<-EOS.undent
-        Some brews install binaries to sbin instead of bin, but Homebrew's
-        sbin was not found in your path.
-
-        Consider editing your .bashrc to add:
+    unless $seen_prefix_sbin
+      <<-EOS.undent
+        Homebrew's sbin was not found in your path.
+        Consider ammending your PATH variable so it contains:
           #{HOMEBREW_PREFIX}/sbin
-        to the PATH variable.
-
-        EOS
+      EOS
     end
   end
 end
@@ -444,13 +414,12 @@ def check_which_pkg_config
   return if binary.empty?
 
   unless binary == "#{HOMEBREW_PREFIX}/bin/pkg-config"
-    puts <<-EOS.undent
+    <<-EOS.undent
       You have a non-brew 'pkg-config' in your PATH:
         #{binary}
 
       `./configure` may have problems finding brew-installed packages using
       this other pkg-config.
-
     EOS
   end
 end
@@ -470,7 +439,7 @@ def check_pkg_config_paths
 
   # Check that all expected paths are being searched
   unless pkg_config_paths.include? "/usr/X11/lib/pkgconfig"
-    puts <<-EOS.undent
+    <<-EOS.undent
       Your pkg-config is not checking "/usr/X11/lib/pkgconfig" for packages.
       Earlier versions of the pkg-config formula did not add this path
       to the search path, which means that other formula may not be able
@@ -478,7 +447,6 @@ def check_pkg_config_paths
 
       To resolve this issue, re-brew pkg-config with:
         brew rm pkg-config && brew install pkg-config
-
     EOS
   end
 end
@@ -487,9 +455,8 @@ def check_for_gettext
   if %w[lib/libgettextlib.dylib
         lib/libintl.dylib
         include/libintl.h ].any? { |f| File.exist? "#{HOMEBREW_PREFIX}/#{f}" }
-    puts <<-EOS.undent
+    <<-EOS.undent
       gettext was detected in your PREFIX.
-
       The gettext provided by Homebrew is "keg-only", meaning it does not
       get linked into your PREFIX by default.
 
@@ -499,7 +466,6 @@ def check_for_gettext
 
       If you have a non-Homebrew provided gettext, other problems will happen
       especially if it wasn't compiled with the proper architectures.
-
     EOS
   end
 end
@@ -507,16 +473,14 @@ end
 def check_for_iconv
   if %w[lib/libiconv.dylib
         include/iconv.h ].any? { |f| File.exist? "#{HOMEBREW_PREFIX}/#{f}" }
-    puts <<-EOS.undent
+    <<-EOS.undent
       libiconv was detected in your PREFIX.
-
       Homebrew doesn't provide a libiconv formula, and expects to link against
       the system version in /usr/lib.
 
       If you have a non-Homebrew provided libiconv, many formulae will fail
       to compile or link, especially if it wasn't compiled with the proper
       architectures.
-
     EOS
   end
 end
@@ -527,7 +491,7 @@ def check_for_config_scripts
   config_scripts = []
 
   path_folders.each do |p|
-    next if ['/usr/bin', '/usr/sbin', '/usr/X11/bin', '/usr/X11R6/bin', "#{HOMEBREW_PREFIX}/bin", "#{HOMEBREW_PREFIX}/sbin"].include? p
+    next if ['/usr/bin', '/usr/sbin', '/usr/X11/bin', '/usr/X11R6/bin', "#{HOMEBREW_PREFIX}/bin", "#{HOMEBREW_PREFIX}/sbin", "/opt/X11/bin"].include? p
     next if p =~ %r[^(#{real_cellar.to_s}|#{HOMEBREW_CELLAR.to_s})] if real_cellar
 
     configs = Dir["#{p}/*-config"]
@@ -536,41 +500,40 @@ def check_for_config_scripts
   end
 
   unless config_scripts.empty?
-    puts <<-EOS.undent
-      Some "config" scripts were found in your path, but not in system or
-      Homebrew directories.
-
+    s = <<-EOS.undent
+      "config" scripts exist outside your system or Homebrew directories.
       `./configure` scripts often look for *-config scripts to determine if
       software packages are installed, and what additional flags to use when
       compiling and linking.
 
       Having additional scripts in your path can confuse software installed via
       Homebrew if the config script overrides a system or Homebrew provided
-      script of the same name.
+      script of the same name. We found the following "config" scripts:
 
     EOS
 
     config_scripts.each do |pair|
-      puts pair[0]
-      puts "    " + pair[1] * " "
+      dn = pair[0]
+      pair[1].each do |fn|
+        s << "    #{dn}/#{fn}\n"
+      end
     end
-    puts
+    s
   end
 end
 
 def check_for_dyld_vars
   if ENV['DYLD_LIBRARY_PATH']
-    puts <<-EOS.undent
+    <<-EOS.undent
       Setting DYLD_LIBRARY_PATH can break dynamic linking.
       You should probably unset it.
-
     EOS
   end
 end
 
 def check_for_symlinked_cellar
   if HOMEBREW_CELLAR.symlink?
-    puts <<-EOS.undent
+    <<-EOS.undent
       Symlinked Cellars can cause problems.
       Your Homebrew Cellar is a symlink: #{HOMEBREW_CELLAR}
                       which resolves to: #{HOMEBREW_CELLAR.realpath}
@@ -582,7 +545,6 @@ def check_for_symlinked_cellar
       Older installations of Homebrew may have created a symlinked Cellar, but this can
       cause problems when two formula install to locations that are mapped on top of each
       other during the linking step.
-
     EOS
   end
 end
@@ -603,33 +565,23 @@ def check_for_multiple_volumes
 
   Dir.delete tmp
 
-  unless where_cellar == where_temp
-    puts <<-EOS.undent
-      Your Cellar and TEMP directories are on different volumes.
-
-      OS X won't move relative symlinks across volumes unless the target file
-      already exists.
-
-      Brews known to be affected by this are Git and Narwhal.
-
-      You should set the "HOMEBREW_TEMP" environmental variable to a suitable
-      directory on the same volume as your Cellar.
+  unless where_cellar == where_temp then <<-EOS.undent
+    Your Cellar and TEMP directories are on different volumes.
+    OS X won't move relative symlinks across volumes unless the target file already
+    exists. Brews known to be affected by this are Git and Narwhal.
 
+    You should set the "HOMEBREW_TEMP" environmental variable to a suitable
+    directory on the same volume as your Cellar.
     EOS
   end
 end
 
 def check_for_git
-  unless system "/usr/bin/which -s git"
-    puts <<-EOS.undent
-      "Git" was not found in your path.
-
-      Homebrew uses Git for several internal functions, and some formulae
-      use Git checkouts instead of stable tarballs.
-
-      You may want to install git:
-        brew install git
-
+  unless system "/usr/bin/which -s git" then <<-EOS.undent
+    Git could not be found in your PATH.
+    Homebrew uses Git for several internal functions, and some formulae use Git
+    checkouts instead of stable tarballs. You may want to install Git:
+      brew install git
     EOS
   end
 end
@@ -640,8 +592,7 @@ def check_git_newline_settings
   autocrlf = `git config --get core.autocrlf`.chomp
   safecrlf = `git config --get core.safecrlf`.chomp
 
-  if autocrlf == 'input' and safecrlf == 'true'
-    puts <<-EOS.undent
+  if autocrlf == 'input' and safecrlf == 'true' then <<-EOS.undent
     Suspicious Git newline settings found.
 
     The detected Git newline settings can cause checkout problems:
@@ -650,7 +601,6 @@ def check_git_newline_settings
 
     If you are not routinely dealing with Windows-based projects,
     consider removing these settings.
-
     EOS
   end
 end
@@ -660,13 +610,11 @@ def check_for_autoconf
 
   autoconf = `/usr/bin/which autoconf`.chomp
   safe_autoconfs = %w[/usr/bin/autoconf /Developer/usr/bin/autoconf]
-  unless autoconf.empty? or safe_autoconfs.include? autoconf
-    puts <<-EOS.undent
-      An "autoconf" in your path blocking the Xcode-provided version at:
-        #{autoconf}
-
-      This custom autoconf may cause some Homebrew formulae to fail to compile.
+  unless autoconf.empty? or safe_autoconfs.include? autoconf then <<-EOS.undent
+    An "autoconf" in your path blocks the Xcode-provided version at:
+      #{autoconf}
 
+    This custom autoconf may cause some Homebrew formulae to fail to compile.
     EOS
   end
 end
@@ -703,9 +651,8 @@ def check_for_linked_kegonly_brews
   end
 
   unless warnings.empty?
-    puts <<-EOS.undent
+    s = <<-EOS.undent
     Some keg-only formula are linked into the Cellar.
-
     Linking a keg-only formula, such as gettext, into the cellar with
     `brew link f` will cause other formulae to detect them during the
     `./configure` step. This may cause problems when compiling those
@@ -715,87 +662,67 @@ def check_for_linked_kegonly_brews
     with other strange results.
 
     You may wish to `brew unlink` these brews:
-    EOS
 
-    puts *warnings.keys.collect { |f| "    #{f}" }
-    puts
+    EOS
+    warnings.keys.each{ |f| s << "    #{f}\n" }
+    s
   end
 end
 
 def check_for_MACOSX_DEPLOYMENT_TARGET
   target_var = ENV['MACOSX_DEPLOYMENT_TARGET']
-  return if target_var.to_s.empty?
-
-  unless target_var == MACOS_VERSION.to_s
-    puts <<-EOS.undent
+  if target_var and target_var != MACOS_VERSION.to_s then <<-EOS.undent
     MACOSX_DEPLOYMENT_TARGET was set to #{target_var}
     This is used by Fink, but having it set to a value different from the
     current system version (#{MACOS_VERSION}) can cause problems, compiling
     Git for instance, and should probably be removed.
-
     EOS
   end
 end
 
 def check_for_other_frameworks
   # Other frameworks that are known to cause problems when present
-  ["/Library/Frameworks/expat.framework", "/Library/Frameworks/libexpat.framework"].each do |f|
-    if File.exist? f
-      puts <<-EOS.undent
-        #{f} detected
-
-        This will be picked up by Cmake's build system and likely cause the
-        build to fail, trying to link to a 32-bit version of expat.
-        You may need to move this file out of the way to compile Cmake.
-
+  %w{Mono.framework expat.framework libexpat.framework}.
+    map{ |frmwrk| "/Library/Frameworks/#{frmwrk}" }.
+    select{ |frmwrk| File.exist? frmwrk }.
+    map do |frmwrk| <<-EOS.undent
+      #{frmwrk} detected
+      This can be picked up by CMake's build system and likely cause the build to
+      fail. You may need to move this file out of the way to compile CMake.
       EOS
-    end
-  end
-
-  if File.exist? "/Library/Frameworks/Mono.framework"
-    puts <<-EOS.undent
-      /Library/Frameworks/Mono.framework detected
-
-      This can be picked up by Cmake's build system and likely cause the
-      build to fail, finding improper header files for libpng for instance.
-
-    EOS
-  end
+    end.join
 end
 
 def check_tmpdir
   tmpdir = ENV['TMPDIR']
-  return if tmpdir.nil?
-  if !File.directory?(tmpdir)
-    puts "TMPDIR #{tmpdir.inspect} doesn't exist."
-    puts
-  end
+  "TMPDIR #{tmpdir.inspect} doesn't exist." unless tmpdir.nil? or File.directory? tmpdir
 end
 
 def check_missing_deps
   s = `brew missing`.strip
-  if s.length > 0
-    ohai "You should brew install these missing dependencies:"
-    puts s
-    puts
+  if s.length > 0 then <<-EOS.undent
+    You have missing dependencies for install formula
+    You should `brew install` these missing dependencies:
+    #{s}
+    EOS
   end
 end
 
 def check_git_status
   HOMEBREW_REPOSITORY.cd do
     cmd = `git status -s Library/Homebrew/ 2> /dev/null`.chomp
-    if system "/usr/bin/which -s git" and File.directory? '.git' and not cmd.empty?
-      ohai "You have uncommitted modifications to Homebrew's core."
-      puts "Unless you know what you are doing, you should run:"
-      puts "cd "+HOMEBREW_REPOSITORY+" && git reset --hard"
-      puts
+    if system "/usr/bin/which -s git" and File.directory? '.git' and not cmd.empty? then <<-EOS.undent
+      You have uncommitted modifications to Homebrew's core.
+      Unless you know what you are doing, you should run:
+        cd #{HOMEBREW_REPOSITORY} && git reset --hard
+      EOS
     end
   end
 end
 
 def check_for_leopard_ssl
   if MacOS.leopard? and not ENV['GIT_SSL_NO_VERIFY']
-    puts <<-EOS.undent
+    <<-EOS.undent
       The version of libcurl provided with Mac OS X Leopard has outdated
       SSL certificates.
 
@@ -805,7 +732,6 @@ def check_for_leopard_ssl
 
       You can force Git to ignore these errors by setting GIT_SSL_NO_VERIFY.
         export GIT_SSL_NO_VERIFY=1
-
     EOS
   end
 end
@@ -815,90 +741,43 @@ def check_git_version
   return unless system "/usr/bin/which -s git"
   `git --version`.chomp =~ /git version (\d)\.(\d)\.(\d)/
 
-  if $2.to_i > 6
-    return
-  elsif $2.to_i == 6 and $3.to_i == 6
-    return
-  else
-    puts <<-EOS.undent
-      An outdated version of Git was detected in your PATH.
-
-      Git 1.6.6 or newer is required to perform checkouts over HTTP from GitHub.
-
-      You may want to upgrade:
-        brew upgrade git
-
+  if $2.to_i < 6 or $2.to_i == 6 and $3.to_i < 6 then <<-EOS.undent
+    An outdated version of Git was detected in your PATH.
+    Git 1.6.6 or newer is required to perform checkouts over HTTP from GitHub.
+    Please upgrade: brew upgrade git
     EOS
   end
 end
 
 def check_for_enthought_python
-  return unless system "/usr/bin/which -s enpkg"
-  puts <<-EOS.undent
+  if system "/usr/bin/which -s enpkg" then <<-EOS.undent
     Enthought Python was found in your PATH.
-
     This can cause build problems, as this software installs its own
     copies of iconv and libxml2 into directories that are picked up by
     other build systems.
-
-  EOS
+    EOS
+  end
 end
 
+end # end class Checks
+
 module Homebrew extend self
   def doctor
-    old_stdout = $stdout
-    $stdout = output = StringIO.new
-
-    begin
-      check_usr_bin_ruby
-      check_homebrew_prefix
-      check_xcode_prefix
-      check_xcode_select_path
-      check_for_macgpg2
-      check_for_stray_dylibs
-      check_for_stray_static_libs
-      check_for_stray_pcs
-      check_for_stray_las
-      check_gcc_versions
-      check_for_other_package_managers
-      check_for_x11
-      check_for_nonstandard_x11
-      check_access_usr_local
-      check_access_include
-      check_access_etc
-      check_access_share
-      check_access_share_locale
-      check_access_share_man
-      check_user_path
-      check_which_pkg_config
-      check_pkg_config_paths
-      check_access_pkgconfig
-      check_for_gettext
-      check_for_config_scripts
-      check_for_dyld_vars
-      check_for_MACOSX_DEPLOYMENT_TARGET
-      check_for_symlinked_cellar
-      check_for_multiple_volumes
-      check_for_git
-      check_git_newline_settings
-      check_for_autoconf
-      check_for_linked_kegonly_brews
-      check_for_other_frameworks
-      check_tmpdir
-      check_missing_deps
-      check_git_status
-      check_for_leopard_ssl
-      check_git_version
-      check_for_enthought_python
-    ensure
-      $stdout = old_stdout
+    raring_to_brew = true
+
+    checks = Checks.new
+
+    checks.methods.select{ |method| method =~ /^check_/ }.sort.each do |method|
+      out = checks.send(method)
+      unless out.nil? or out.empty?
+        puts unless raring_to_brew
+        lines = out.to_s.split('\n')
+        opoo lines.shift
+        puts lines
+        raring_to_brew = false
+      end
     end
 
-    unless (warnings = output.string).chomp.empty?
-      puts warnings
-      exit 1
-    else
-      puts "Your system is raring to brew."
-    end
+    puts "Your system is raring to brew." if raring_to_brew
   end
 end