More useful Macports/Fink detection function

Library/Homebrew/brew.h.rb

@@ -262,8 +262,7 @@ def diy
   end
 end
 
-
-def warn_about_macports_or_fink
+def macports_or_fink_installed?
   # See these issues for some history:
   # http://github.com/mxcl/homebrew/issues/#issue/13
   # http://github.com/mxcl/homebrew/issues/#issue/41
@@ -271,10 +270,7 @@ def warn_about_macports_or_fink
 
   %w[port fink].each do |ponk|
     path = `/usr/bin/which -s #{ponk}`
-    unless path.empty?
-      opoo "It appears you have Macports or Fink in your PATH"
-      puts "If formula fail to build try renaming or uninstalling these tools."
-    end
+    return ponk unless path.empty?
   end
 
   # we do the above check because macports can be relocated and fink may be
@@ -282,24 +278,20 @@ def warn_about_macports_or_fink
   # fink and macports are not in the PATH but are still installed it can
   # *still* break the build -- because some build scripts hardcode these paths:
   %w[/sw/bin/fink /opt/local/bin/port].each do |ponk|
-    if File.exist? ponk
-      opoo "It appears you have MacPorts or Fink installed"
-      puts "If formula fail to build, consider renaming: %s" % Pathname.new(ponk).dirname.parent
-    end
+    return ponk if File.exist? ponk
   end
 
-  # finally sometimes people make their MacPorts or Fink read-only so they
+  # finally, sometimes people make their MacPorts or Fink read-only so they
   # can quickly test Homebrew out, but still in theory obey the README's 
   # advise to rename the root directory. This doesn't work, many build scripts
   # error out when they try to read from these now unreadable directories.
   %w[/sw /opt/local].each do |path|
-    if File.exist? path and not File.readable? path
-      opoo "It appears you have MacPorts or Fink installed"
-      puts "This has been known to cause build fails and other more subtle problems."
-    end
-  end
+    path = Pathname.new(path)
+    return path if path.exist? and not path.readable?
   end
   
+  false
+end
 
 def versions_of(keg_name)
   `ls #{HOMEBREW_CELLAR}/#{keg_name}`.collect { |version| version.strip }.reverse

bin/brew

@@ -296,7 +296,8 @@ rescue Exception => e
   puts "Please report this bug at: #{HOMEBREW_WWW}"
   puts "Please include the following information:"
   ohai "Environment"
-  puts "Mac OS X: "+`sw_vers -productVersion`
+  puts "Mac OS X #{MACOS_VERSION}"
+  puts "Macports or Fink? #{macports_or_fink_installed?}"
   ohai e.inspect
   puts e.backtrace
   exit 1