Tests and a small bug fix to make them pass

middleman-core/features/strip_url.feature

@@ -0,0 +1,40 @@
+Feature: Strip the index_file from urls
+
+  Scenario: Default behaviour, strip with trailing slash
+    Given the Server is running at "strip-url-app"
+    When I go to "/"
+    Then I should see "URL: '/'"
+    When I go to "/index.html"
+    Then I should see "URL: '/'"
+    When I go to "/other.html"
+    Then I should see "URL: '/other.html'"
+    When I go to "/subdir/index.html"
+    Then I should see "URL: '/subdir/'"
+
+  Scenario: Trailing slash off
+    Given a fixture app "strip-url-app"
+    And a file named "config.rb" with:
+       """
+       set :trailing_slash, false
+       """
+    And the Server is running
+    When I go to "/"
+    Then I should see "URL: '/'"
+    When I go to "/other.html"
+    Then I should see "URL: '/other.html'"
+    When I go to "/subdir/index.html"
+    Then I should see "URL: '/subdir'"
+
+  Scenario: Strip index off
+    Given a fixture app "strip-url-app"
+    And a file named "config.rb" with:
+       """
+       set :strip_index_file, false
+       """
+    And the Server is running
+    When I go to "/"
+    Then I should see "URL: '/index.html'"
+    When I go to "/other.html"
+    Then I should see "URL: '/other.html'"
+    When I go to "/subdir/index.html"
+    Then I should see "URL: '/subdir/index.html'"

middleman-core/fixtures/strip-url-app/source/index.html.erb

@@ -0,0 +1 @@
+URL: '<%= current_page.url %>'

middleman-core/fixtures/strip-url-app/source/other.html.erb

@@ -0,0 +1 @@
+URL: '<%= current_page.url %>'

middleman-core/fixtures/strip-url-app/source/subdir/index.html.erb

@@ -0,0 +1 @@
+URL: '<%= current_page.url %>'

middleman-core/lib/middleman-core/sitemap/resource.rb

@@ -143,7 +143,7 @@ module Middleman
       def url
         url_path = destination_path
         if app.strip_index_file
-          url_path = url_path.sub(/\/#{Regexp.escape(app.index_file)}$/,
+          url_path = url_path.sub(/(^|\/)#{Regexp.escape(app.index_file)}$/,
                                   app.trailing_slash ? '/' : '')
         end
         File.join(app.respond_to?(:http_prefix) ? app.http_prefix : '/', url_path)