Improve SpecHelpers to work consistently. Use 'include' instead of 'extend' + use_fakefs. Add specs.

lib/fakefs/spec_helpers.rb

@@ -1,37 +1,43 @@
 # FakeFS::SpecHelpers provides a simple macro for RSpec example groups to turn FakeFS on and off.
-# To use it simply require 'fakefs/safe' and 'fakefs/spec_helpers'.  Then include FakeFS::SpecHelpers into any
-# example groups that you wish to use FakeFS in.  The "use_fakefs" macro is then available to install
-# before and after hooks which will enable and disable FakeFS.  For example:
+# To use it simply require 'fakefs/spec_helpers', then include FakeFS::SpecHelpers into any
+# example groups that you wish to use FakeFS in. For example:
 #
-#   require 'fakefs/safe'
 #   require 'fakefs/spec_helpers'
 #
 #   describe "Some specs that deal with files" do
-#     extend FakeFS::SpecHelpers
-#     use_fakefs
+#     include FakeFS::SpecHelpers
 #     ...
 #   end
 #
 # Alternatively, you can include FakeFS::SpecHelpers in all your example groups using RSpec's
 # configuration block in your spec helper:
 #
-#   require 'fakefs/safe'
 #   require 'fakefs/spec_helpers'
 #
 #   Spec::Runner.configure do |config|
-#     config.extend FakeFS::SpecHelpers
+#     config.include FakeFS::SpecHelpers
 #   end
 #
 # If you do the above then use_fakefs will be available in all of your example groups.
 #
+require 'fakefs/safe'
+
 module FakeFS
   module SpecHelpers
-    def use_fakefs
-      before(:each) do
+    def self.extended(example_group)
+      example_group.use_fakefs(example_group)
+    end
+
+    def self.included(example_group)
+      example_group.extend self
+    end
+
+    def use_fakefs(describe_block)
+      describe_block.before :each do
         FakeFS.activate!
       end
 
-      after(:each) do
+      describe_block.after :each do
         FakeFS.deactivate!
         FakeFS::FileSystem.clear
       end

spec/fakefs/spec_helpers_spec.rb

@@ -0,0 +1,57 @@
+require 'spec_helper'
+
+module FakeFS
+  describe SpecHelpers do
+    before do
+      @rspec_example_group = Class.new do
+        def self.before(sym = :each)
+          yield if block_given?
+        end
+
+        def self.after(sym = :each)
+          yield if block_given?
+        end
+      end
+    end
+
+    describe "when extending" do
+      context "before each" do
+        it "should call it" do
+          @rspec_example_group.should_receive(:before).with(:each)
+          @rspec_example_group.extend FakeFS::SpecHelpers
+        end
+
+        it "should call FakeFS.activate!" do
+          FakeFS.should_receive(:activate!)
+          @rspec_example_group.extend FakeFS::SpecHelpers
+        end
+      end
+
+      context "after each" do
+        it "should call it" do
+          @rspec_example_group.should_receive(:after).with(:each)
+          @rspec_example_group.extend FakeFS::SpecHelpers
+        end
+
+        it "should deactivate fakefs" do
+          FakeFS.should_receive(:deactivate!)
+          @rspec_example_group.extend FakeFS::SpecHelpers
+        end
+
+        it "should clear the fakefs filesystem for the next run" do
+          FakeFS::FileSystem.should_receive(:clear)
+          @rspec_example_group.extend FakeFS::SpecHelpers
+        end
+      end
+    end
+
+    describe "when including" do
+      it "should call before :each" do
+        @rspec_example_group.should_receive(:before)
+        @rspec_example_group.class_eval do
+          include FakeFS::SpecHelpers
+        end
+      end
+    end
+  end
+end

spec/spec.opts

@@ -0,0 +1 @@
+--color

spec/spec_helper.rb

@@ -0,0 +1,3 @@
+$LOAD_PATH.unshift File.join(File.dirname(__FILE__), '..', 'lib')
+
+require 'fakefs/spec_helpers'