Use file ext from stream by default

index.js

@@ -24,7 +24,6 @@ module.exports = function(options) {
   'use strict';
 
   var opts = options ? clone(options) : {};
-  opts.ext = opts.ext || ".html";
 
   if (opts.defaults) {
     swig.setDefaults(opts.defaults);
@@ -65,7 +64,7 @@ module.exports = function(options) {
       var tpl = _swig.compile(String(file.contents), {filename: file.path});
       var compiled = tpl(data);
 
-      file.path = ext(file.path, opts.ext);
+      file.path = opts.ext ? ext(file.path, opts.ext) : file.path;
       file.contents = new Buffer(compiled);
 
       callback(null, file);

test/fixtures/test.css

@@ -0,0 +1 @@
+body { color: white; }

test/test.js

@@ -18,13 +18,18 @@ describe('gulp-swig compilation', function() {
     var filename_without_json = path.join(__dirname, './fixtures/test4.html');
     var filename_with_markdown = path.join(__dirname, './fixtures/test3.html');
     var filename_with_varControls = path.join(__dirname, './fixtures/test5.html');
+    var filename_different_ext = path.join(__dirname, './fixtures/test.css');
 
     function expectStream(done, options) {
       options = options || {};
       return es.map(function(file) {
         var result = String(file.contents);
         var expected = options.expected;
         expect(result).to.equal(expected);
+        if (options.expectedExt) {
+          var expectedExt = options.expectedExt;
+          expect(path.extname(file.path)).to.equal(expectedExt);
+        }
         done();
       });
     }
@@ -138,6 +143,28 @@ describe('gulp-swig compilation', function() {
         .pipe(expectStream(done, opts));
     });
 
+    it('should use the file extension from the stream by default', function(done) {
+      var opts = {
+        load_json: true,
+        expected: 'body { color: white; }\n',
+        expectedExt: '.css'
+      };
+      gulp.src(filename_different_ext)
+          .pipe(task(opts))
+          .pipe(expectStream(done, opts));
+    });
+
+    it('should use the file extension from opts.ext instead of the stream', function(done) {
+      var opts = {
+        ext: '.less',
+        load_json: true,
+        expected: 'body { color: white; }\n',
+        expectedExt: '.less'
+      };
+      gulp.src(filename_different_ext)
+          .pipe(task(opts))
+          .pipe(expectStream(done, opts));
+    });
   });
 
 });