CacheBustingFilter: better handling of dots in file names

lib/rake-pipeline-web-filters/cache_buster_filter.rb

@@ -25,7 +25,8 @@ def initialize(&key_generator)
       key_generator ||= DEFAULT_KEY_GENERATOR
       output_name_generator = proc { |path, file|
         parts = path.split('.')
-        parts[0] << "-#{key_generator.call(file)}"
+        index_to_modify = parts.length > 1 ? -2 : -1
+        parts[index_to_modify] << "-#{key_generator.call(file)}"
         parts.join('.')
       }
       super(&output_name_generator)

spec/cache_buster_filter_spec.rb

@@ -69,4 +69,37 @@ def setup_filter(filter)
     end
 
   end
+
+  describe 'for an input file with multiple dots' do
+    let(:input_file) {
+      MemoryFileWrapper.new '/path/to/input', 'my.text.file.txt', 'UTF-8', content
+    }
+
+    let(:output_file) {
+      MemoryFileWrapper.new output_root, "my.text.file-foo.txt", 'UTF-8'
+    }
+
+    subject { setup_filter(CacheBusterFilter.new() { 'foo' }) }
+
+    it 'appends the busting key to the penultimate part' do
+      subject.output_files.should == [ output_file ]
+    end
+  end
+
+  describe 'for an input file with no dots' do
+    let(:input_file) {
+      MemoryFileWrapper.new '/path/to/input', 'my_text_file', 'UTF-8', content
+    }
+
+    let(:output_file) {
+      MemoryFileWrapper.new output_root, "my_text_file-foo", 'UTF-8'
+    }
+
+    subject { setup_filter(CacheBusterFilter.new() { 'foo' }) }
+
+    it 'appends the busting key to the end of the filename' do
+      subject.output_files.should == [ output_file ]
+    end
+  end
+
 end