test this fix with a cucumber feature

features/create_sites.feature

@@ -110,3 +110,14 @@ Feature: Create sites
     When I run jekyll
     Then the _site directory should exist
     And I should see "SomeDirective" in "_site/.htaccess"
+
+  Scenario: File was replaced by a directory
+    Given I have a "test" file that contains "some stuff"
+    When I run jekyll
+    Then the _site directory should exist
+    When I delete the file "test"
+    Given I have a test directory
+    And I have a "test/index.html" file that contains "some other stuff"
+    When I run jekyll
+    Then the _site/test directory should exist
+    And I should see "some other stuff" in "_site/test/index.html"

features/step_definitions/jekyll_steps.rb

@@ -140,6 +140,10 @@ When /^I change "(.*)" to contain "(.*)"$/ do |file, text|
   end
 end
 
+When /^I delete the file "(.*)"$/ do |file|
+  File.delete(file)
+end
+
 Then /^the (.*) directory should exist$/ do |dir|
   assert File.directory?(dir), "The directory \"#{dir}\" does not exist"
 end