add striping of Content-* fields when 204 / 304. Closes #21

lib/context.js

@@ -71,6 +71,12 @@ module.exports = {
       val = n;
     }
 
+    if (204 == val || 304 == val) {
+      this.res.removeHeader('Content-Type');
+      this.res.removeHeader('Content-Length');
+      this.res.removeHeader('Transfer-Encoding');
+    }
+
     this.res.statusCode = val;
   },
 

test/context.js

@@ -1,5 +1,6 @@
 
 var _context = require('../lib/context');
+var request = require('supertest');
 var assert = require('assert');
 var koa = require('..');
 var fs = require('fs');
@@ -172,6 +173,29 @@ describe('ctx.status=', function(){
       })
     })
   })
+
+  describe('when 204', function(){
+    it('should strip content related header fields', function(done){
+      var app = koa();
+
+      app.use(function(next){
+        return function *(){
+          this.set('Content-Type', 'application/json');
+          this.set('Content-Length', '15');
+          this.set('Transfer-Encoding', 'chunked');
+          this.status = 204;
+          assert(null == this.responseHeader['content-type']);
+          assert(null == this.responseHeader['content-length']);
+          assert(null == this.responseHeader['transfer-encoding']);
+        }
+      });
+
+      request(app.listen())
+        .get('/')
+        .expect(204)
+        .end(done);
+    })
+  })
 })
 
 describe('ctx.stale', function(){