fix: decompress response data

lib/adapters/http.js

@@ -402,7 +402,11 @@ export default isHttpAdapterSupported && function httpAdapter(config) {
       if (config.decompress !== false) {
         // if no content, but headers still say that it is encoded,
         // remove the header not confuse downstream operations
-        if ((!responseLength || res.statusCode === 204) && res.headers['content-encoding']) {
+        if (
+          (!responseLength || res.statusCode === 204) &&
+          res.headers['content-encoding'] &&
+          !res.headers['transfer-encoding']
+        ) {
           delete res.headers['content-encoding'];
         }
 

test/unit/adapters/http.js

@@ -466,6 +466,28 @@ describe('supports http with nodejs', function () {
     })
   });
 
+    it('should support decompression of response data', function(done) {
+      var data = 'Test data';
+
+      zlib.gzip(data, function(err, zipped) {
+        server = http.createServer(function(req, res) {
+          res.setHeader('Content-Type', 'text/html;charset=utf-8');
+          res.setHeader('Content-Encoding', 'gzip');
+          res.setHeader('Transfer-Encoding', 'chunked');
+          res.end(zipped);
+        }).listen(4444, function() {
+          axios.get('http://localhost:4444/', {
+            decompress: true,
+            responseType: 'arraybuffer'
+
+          }).then(function(res) {
+            assert.equal(res.data, data);
+            done();
+          }).catch(done);
+        });
+      });
+    });
+
     it('should support disabling automatic decompression of response data', function(done) {
       var data = 'Test data';