fixed

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@bytedo/fetch",
-  "version": "1.0.0",
+  "version": "1.0.1",
   "description": "全新的ajax封装。分2个版本, 一个基于XMLHttpRequest, 一个基于window.fetch",
   "main": "dist/index.js",
   "directories": {

src/index.es7

@@ -77,11 +77,18 @@ class _Request {
       control.abort()
     }
 
-    if (__INIT__.headers && options.headers) {
-      Object.assign(__INIT__.headers, options.headers)
+    var headers = this.options.headers
+
+    if (__INIT__.headers) {
+      Object.assign(headers, __INIT__.headers)
     }
 
-    Object.assign(this.options, __INIT__, options, { url })
+    if (options.headers) {
+      Object.assign(headers, options.headers)
+      delete options.headers
+    }
+
+    Object.assign(this.options, __INIT__, options, { url, headers })
 
     this.__next__()
     return this.defer.promise

src/next.es7

@@ -50,11 +50,18 @@ class _Request {
       options.signal = this.control.signal
     }
 
-    if (__INIT__.headers && options.headers) {
-      Object.assign(__INIT__.headers, options.headers)
+    var headers = this.options.headers
+
+    if (__INIT__.headers) {
+      Object.assign(headers, __INIT__.headers)
     }
 
-    Object.assign(this.options, __INIT__, options, { url })
+    if (options.headers) {
+      Object.assign(headers, options.headers)
+      delete options.headers
+    }
+
+    Object.assign(this.options, __INIT__, options, { url, headers })
 
     return this.__next__()
   }