test: add test for enforceEnconding

Author: bjohansebas

index.js

@@ -45,7 +45,7 @@ var cacheControlNoTransformRegExp = /(?:^|,)\s*?no-transform\s*?(?:,|$)/
 var SUPPORTED_ENCODING = hasBrotliSupport ? ['br', 'gzip', 'deflate', 'identity'] : ['gzip', 'deflate', 'identity']
 var PREFERRED_ENCODING = hasBrotliSupport ? ['br', 'gzip'] : ['gzip']
 
-var encodingSupported = ['*', 'gzip', 'deflate', 'identity']
+var encodingSupported = ['*', 'gzip', 'deflate', 'identity', 'br']
 
 /**
  * Compress response data with gzip / deflate.
@@ -207,6 +207,7 @@ function compression (options) {
         nocompress('not acceptable')
         return
       }
+
       // compression stream
       debug('%s compression', method)
       stream = method === 'gzip'

test/compression.js

@@ -934,6 +934,19 @@ describe('compression()', function () {
         .expect(200, 'hello, world', done)
     })
 
+    brotli('should compress when enforceEncoding is brotli', function (done) {
+      var server = createServer({ threshold: 0, enforceEncoding: 'br' }, function (req, res) {
+        res.setHeader('Content-Type', 'text/plain')
+        res.end('hello, world')
+      })
+
+      request(server)
+        .get('/')
+        .set('Accept-Encoding', '')
+        .expect('Content-Encoding', 'br')
+        .expect(200, done)
+    })
+
     it('should not compress when enforceEncoding is unknown', function (done) {
       var server = createServer({ threshold: 0, enforceEncoding: 'bogus' }, function (req, res) {
         res.setHeader('Content-Type', 'text/plain')