better qt building?

ext/jasmine-webkit-specrunner/extconf.rb

@@ -1,8 +1,6 @@
-case RUBY_PLATFORM
-when /linux/
-	system %{qmake -spec linux-g++}
-else
-	system %{qmake -spec macx-g++}
-end
+$: << File.expand_path("../../../lib", __FILE__)
+
+require 'qt/qmake'
+
+Qt::Qmake.make!('jasmine-headless-webkit')
 
-system %{make}

lib/qt/qmake.rb

@@ -0,0 +1,143 @@
+require 'rbconfig'
+
+module Qt
+  class NotInstalledError < StandardError; end
+
+  class Qmake
+    class << self
+      def installed?
+        path != nil
+      end
+
+      def make_installed?
+        make_path != nil
+      end
+
+      def command
+        case platform
+        when :linux
+          "#{path} -spec linux-g++"
+        when :mac_os_x
+          "#{path} -spec macx-g++"
+        end
+      end
+
+      def make!(name)
+        @name = name
+
+        check_make!
+        check_qmake!
+        check_qmake_version!
+
+        system command
+        system %{make}
+      end
+
+      #
+      # We need integration tests for these!
+      #
+      def path
+        get_exe_path('qmake')
+      end
+
+      def make_path
+        get_exe_path('make')
+      end
+
+      def platform
+        case RbConfig::CONFIG['host_os']
+        when /linux/
+          :linux
+        when /darwin/
+          :mac_os_x
+        end
+      end
+
+      def qt_version
+        @qt_version ||= %x{#{path} -v}.lines.to_a[1][%r{Using Qt version ([^ ]+) },1]
+      end
+
+      def qt_47_or_better?
+        return false if !qt_version
+        return true if (major = qt_version.split('.')[0].to_i) > 4
+        return false if major < 4
+        qt_version.split('.')[1].to_i >= 7
+      end
+
+      private
+      def get_exe_path(command)
+        path = %x{which #{command}}.strip
+        path = nil if path == ''
+        path
+      end
+
+      def check_make!
+        if !make_installed?
+          install_method = (
+            case platform
+            when :linux
+              %{sudo apt-get install make or sudo yum install make}
+            when :darwin
+              %{Install XCode, and/or sudo port install make}
+            end
+          )
+
+          $stderr.puts <<-MSG
+make is not installed. You'll need to install it to build #{@name}.
+#{install_method} should do it for you.
+MSG
+          raise NotInstalledError
+        end
+      end
+
+      def check_qmake!
+        if !installed?
+          install_method = strip(
+            case platform
+            when :linux
+              <<-MSG
+sudo apt-get install libqt4-dev qt4-qmake on Debian-based systems, or downloading
+Nokia's prebuilt binary at http://qt.nokia.com/downloads/
+MSG
+            when :darwin
+              <<-MSG
+sudo port install qt4-mac (for the patient) or downloading Nokia's pre-built binary
+at http://qt.nokia.com/downloads/
+MSG
+            end
+          )
+
+          $stderr.puts <<-MSG
+qmake is not installed. You'll need to install it to build #{@name}.
+#{install_method} should do it for you.
+MSG
+        end
+      end
+
+      def check_qmake_version!
+        if !qt_47_or_better?
+          install_method = strip(
+            case platform
+            when :linux
+              <<-MSG
+sudo apt-get install libqt4-dev qt4-qmake on Debian-based systems, or downloading
+Nokia's prebuilt binary at http://qt.nokia.com/downloads/
+MSG
+            when :darwin
+              <<-MSG
+sudo port install qt4-mac (for the patient) or downloading Nokia's pre-built binary
+at http://qt.nokia.com/downloads/
+MSG
+            end
+          )
+
+          $stderr.puts <<-MSG
+qmake is not version 4.7 or above (currently version #{qt_version}. You'll need to install version 4.7 or higher
+to build #{@name}. #{install_method} should do it for you.
+MSG
+        end
+      end
+    end
+  end
+end
+

spec/lib/qt/qmake_spec.rb

@@ -0,0 +1,93 @@
+require 'spec_helper'
+require 'qt/qmake'
+require 'rbconfig'
+
+describe Qt::Qmake do
+  describe '.make_installed?' do
+    subject { described_class }
+
+    before do
+      Qt::Qmake.stubs(:make_path).returns(path)
+    end
+
+    context 'not installed' do
+      let(:path) { nil }
+
+      it { should_not be_make_installed }
+    end
+
+    context 'installed' do
+      let(:path) { '/here/there/make' }
+
+      it { should be_make_installed }
+    end
+  end
+
+  describe '.installed?' do
+    subject { described_class }
+
+    before do
+      Qt::Qmake.stubs(:path).returns(path) 
+    end
+
+    context 'not installed' do
+      let(:path) { nil }
+
+      it { should_not be_installed }
+    end
+
+    context 'installed' do
+      let(:path) { '/here/there/qmake' }
+
+      it { should be_installed }
+    end
+  end
+
+  describe '.command' do
+    subject { described_class.command }
+
+    before do
+      Qt::Qmake.stubs(:platform).returns(platform)
+      Qt::Qmake.stubs(:path).returns("qmake")
+    end
+
+    context 'linux' do
+      let(:platform) { :linux }
+
+      it { should == "qmake -spec linux-g++" }
+    end
+
+    context 'mac os x' do
+      let(:platform) { :mac_os_x }
+
+      it { should == "qmake -spec macx-g++" }
+    end
+  end
+
+  describe '.qt_47_or_better?' do
+    subject { described_class }
+
+    before do
+      Qt::Qmake.stubs(:qt_version).returns(version)
+    end
+    
+    context 'no version' do
+      let(:version) { nil }
+
+      it { should_not be_qt_47_or_better }
+    end
+
+    context 'not better' do
+      let(:version) { '4.6.0' }
+
+      it { should_not be_qt_47_or_better }
+    end
+
+    context 'better' do
+      let(:version) { '4.7.0' }
+
+      it { should be_qt_47_or_better }
+    end
+  end
+end
+