Move X11 machinery into MacOS::XQuartz namespace

In order to better support Xcode-only systems, where X11 libs and
executables live under /usr/X11 but headers live in the SDK, move the
x11_* helper methods into a new module.

This allows us to keep some of the CLT/Xcode-only and Apple X11/XQuartz
logic hidden from outside code, like ENV.x11.

Since Apple's X11 is actually XQuartz, name the module "MacOS::XQuartz".

Library/Homebrew/cmd/--config.rb

@@ -59,8 +59,8 @@ module Homebrew extend self
   end
 
   def describe_x11
-    return "N/A" unless MacOS.x11_installed?
-    return "#{MacOS.xquartz_version} @ " + describe_path(MacOS.x11_prefix)
+    return "N/A" unless MacOS::XQuartz.installed?
+    return "#{MacOS::XQuartz.version} @ " + describe_path(MacOS::XQuartz.prefix)
   end
 
   def describe_perl

Library/Homebrew/cmd/doctor.rb

@@ -168,7 +168,7 @@ def check_for_stray_las
 end
 
 def check_for_x11
-  unless MacOS.x11_installed? then <<-EOS.undent
+  unless MacOS::XQuartz.installed? then <<-EOS.undent
     X11 is not installed.
     You don't have X11 installed as part of your OS X installation.
     This is not required for all formulae, but is expected by some.

Library/Homebrew/compat/compatibility.rb

@@ -34,7 +34,7 @@ def llvm_build
 end
 
 def x11_installed?
-  MacOS.x11_installed?
+  MacOS::XQuartz.installed?
 end
 
 def macports_or_fink_installed?
@@ -189,4 +189,12 @@ module MacOS extend self
   def clt_version?
     CLT.version
   end
+
+  def x11_installed?
+    XQuartz.installed?
+  end
+
+  def x11_prefix
+    XQuartz.prefix
+  end
 end

Library/Homebrew/dependencies.rb

@@ -189,7 +189,7 @@ class X11Dependency < Requirement
   def fatal?; true; end
 
   def satisfied?
-    MacOS.x11_installed? and (@min_version == nil or @min_version <= MacOS.xquartz_version)
+    MacOS::XQuartz.installed? and (@min_version.nil? or @min_version <= MacOS::XQuartz.version)
   end
 
   def message; <<-EOS.undent

Library/Homebrew/extend/ENV.rb

@@ -310,35 +310,26 @@ Please take one of the following actions:
   end
 
   def x11
-    opoo "You do not have X11 installed, this formula may not build." unless MacOS.x11_installed?
-
-    # There are some config scripts here that should go in the PATH. This
-    # path is always under MacOS.x11_prefix, even for Xcode-only systems.
-    prepend 'PATH', MacOS.x11_prefix/'bin', ':'
-
-    # Similarily, pkgconfig files are only found under MacOS.x11_prefix.
-    prepend 'PKG_CONFIG_PATH', MacOS.x11_prefix/'lib/pkgconfig', ':'
-    prepend 'PKG_CONFIG_PATH', MacOS.x11_prefix/'share/pkgconfig', ':'
-
-    append 'LDFLAGS', "-L#{MacOS.x11_prefix}/lib"
-    append 'CMAKE_PREFIX_PATH', MacOS.x11_prefix, ':'
-
-    # We prefer XQuartz if it is installed. Otherwise, we look for Apple's
-    # X11. For Xcode-only systems, the headers are found in the SDK.
-    prefix = if MacOS.x11_prefix.to_s == '/opt/X11' or MacOS::CLT.installed?
-      MacOS.x11_prefix
-    else
-      MacOS.sdk_path/'usr/X11'
+    unless MacOS::XQuartz.installed?
+      opoo "You do not have X11 installed, this formula may not build."
     end
 
-    append 'CPPFLAGS', "-I#{prefix}/include"
+    # There are some config scripts here that should go in the PATH
+    prepend 'PATH', MacOS::XQuartz.bin, ':'
 
-    append 'CMAKE_PREFIX_PATH', prefix, ':'
-    append 'CMAKE_INCLUDE_PATH', prefix/'include', ':'
+    prepend 'PKG_CONFIG_PATH', MacOS::XQuartz.lib/'pkgconfig', ':'
+    prepend 'PKG_CONFIG_PATH', MacOS::XQuartz.share/'pkgconfig', ':'
+
+    append 'LDFLAGS', "-L#{MacOS::XQuartz.lib}"
+    append 'CMAKE_PREFIX_PATH', MacOS::XQuartz.prefix, ':'
+    append 'CMAKE_INCLUDE_PATH', MacOS::XQuartz.include, ':'
+
+    append 'CPPFLAGS', "-I#{MacOS::XQuartz.include}"
 
     unless MacOS::CLT.installed?
-      append 'CPPFLAGS', "-I#{prefix}/include/freetype2"
-      append 'CFLAGS', "-I#{prefix}/include"
+      append 'CMAKE_PREFIX_PATH', MacOS.sdk_path/'usr/X11', ':'
+      append 'CPPFLAGS', "-I#{MacOS::XQuartz.include}/freetype2"
+      append 'CFLAGS', "-I#{MacOS::XQuartz.include}"
     end
   end
   alias_method :libpng, :x11

Library/Homebrew/macos.rb

@@ -1,8 +1,6 @@
 module MacOS extend self
 
   MDITEM_BUNDLE_ID_KEY = "kMDItemCFBundleIdentifier"
-  APPLE_X11_BUNDLE_ID = "org.x.X11"
-  XQUARTZ_BUNDLE_ID = "org.macosforge.xquartz.X11"
 
   def version
     MACOS_VERSION
@@ -168,28 +166,6 @@ module MacOS extend self
     end
   end
 
-  def xquartz_version
-    # This returns the version number of XQuartz, not of the upstream X.org
-    # (which is why it is not called x11_version). Note that the X11.app
-    # distributed by Apple is also XQuartz, and therefore covered by this method.
-    path = app_with_bundle_id(XQUARTZ_BUNDLE_ID) || app_with_bundle_id(APPLE_X11_BUNDLE_ID)
-    version = if not path.nil? and path.exist?
-      `mdls -raw -name kMDItemVersion "#{path}" 2>/dev/null`.strip
-    end
-  end
-
-  def x11_prefix
-    @x11_prefix ||= if Pathname.new('/opt/X11/lib/libpng.dylib').exist?
-      Pathname.new('/opt/X11')
-    elsif Pathname.new('/usr/X11/lib/libpng.dylib').exist?
-      Pathname.new('/usr/X11')
-    end
-  end
-
-  def x11_installed?
-    not x11_prefix.nil?
-  end
-
   def macports_or_fink_installed?
     # See these issues for some history:
     # http://github.com/mxcl/homebrew/issues/#issue/13
@@ -278,4 +254,5 @@ module MacOS extend self
   end
 end
 
-require 'xcode'
+require 'macos/xcode'
+require 'macos/xquartz'

Library/Homebrew/macos/xquartz.rb

@@ -0,0 +1,64 @@
+module MacOS::XQuartz extend self
+  FORGE_BUNDLE_ID = "org.macosforge.xquartz.X11"
+  APPLE_BUNDLE_ID = "org.x.X11"
+
+  # This returns the version number of XQuartz, not of the upstream X.org.
+  # The X11.app distributed by Apple is also XQuartz, and therefore covered
+  # by this method.
+  def version
+    path = MacOS.app_with_bundle_id(FORGE_BUNDLE_ID) || MacOS.app_with_bundle_id(APPLE_BUNDLE_ID)
+    version = if not path.nil? and path.exist?
+      `mdls -raw -name kMDItemVersion "#{path}" 2>/dev/null`.strip
+    end
+  end
+
+  # This should really be private, but for compatibility reasons it must
+  # remain public. New code should use MacOS::XQuartz.{bin,lib,include}
+  # instead, as that accounts for Xcode-only systems.
+  def prefix
+    @prefix ||= if Pathname.new('/opt/X11/lib/libpng.dylib').exist?
+      Pathname.new('/opt/X11')
+    elsif Pathname.new('/usr/X11/lib/libpng.dylib').exist?
+      Pathname.new('/usr/X11')
+    end
+  end
+
+  def installed?
+    not prefix.nil?
+  end
+
+  # If XQuartz and/or the CLT are installed, headers will be found under
+  # /opt/X11/include or /usr/X11/include. For Xcode-only systems, they are
+  # found in the SDK, so we use sdk_path for both the headers and libraries.
+  # Confusingly, executables (e.g. config scripts) are only found under
+  # /opt/X11/bin or /usr/X11/bin in all cases.
+  def bin
+    prefix/'bin'
+  end
+
+  def include
+    @include ||= if use_sdk?
+      MacOS.sdk_path/'usr/X11/include'
+    else
+      prefix/'include'
+    end
+  end
+
+  def lib
+    @lib ||= if use_sdk?
+      MacOS.sdk_path/'usr/X11/lib'
+    else
+      prefix/'lib'
+    end
+  end
+
+  def share
+    prefix/'share'
+  end
+
+  private
+
+  def use_sdk?
+    not (prefix.to_s == '/opt/X11' or MacOS::CLT.installed?)
+  end
+end