fixes #321

hopefully fixes this issue

Author: Ron Radtke

android/src/main/java/com/ReactNativeBlobUtil/ReactNativeBlobUtilReq.java

@@ -678,7 +678,7 @@ private void done(Response resp) {
                             try (FileOutputStream fos = new FileOutputStream(file)) {
                                 fos.write(ReactNativeBlobUtilFileTransformer.sharedFileTransformer.onWriteFile(b));
                             } catch (Exception e) {
-                                invoke_callback("Error from file transformer:" + e.getLocalizedMessage(), null);
+                                invoke_callback("Error from file transformer:" + e.getLocalizedMessage(),  respmap.copy());
                                 return;
                             }
                             invoke_callback(null, ReactNativeBlobUtilConst.RNFB_RESPONSE_PATH, this.destPath, respmap.copy());
@@ -709,7 +709,7 @@ private void done(Response resp) {
                         }
                     }
                 } catch (IOException e) {
-                    invoke_callback("ReactNativeBlobUtil failed to encode response data to BASE64 string.", null);
+                    invoke_callback("ReactNativeBlobUtil failed to encode response data to BASE64 string.", respmap.copy());
                 }
                 break;
             case FileStorage:
@@ -741,15 +741,15 @@ private void done(Response resp) {
                         } catch (IOException exception) {
                             exception.printStackTrace();
                         }
-                        invoke_callback("Unexpected FileStorage response file: " + responseBodyString, null);
+                        invoke_callback("Unexpected FileStorage response file: " + responseBodyString,  respmap.copy());
                     } else {
-                        invoke_callback("Unexpected FileStorage response with no file.", null);
+                        invoke_callback("Unexpected FileStorage response with no file.",  respmap.copy());
                     }
                     return;
                 }
 
                 if (ReactNativeBlobUtilFileResp != null && !ReactNativeBlobUtilFileResp.isDownloadComplete()) {
-                    invoke_callback("Download interrupted.", null, respmap.copy());
+                    invoke_callback("Download interrupted.", respmap.copy());
                 } else {
                     this.destPath = this.destPath.replace("?append=true", "");
                     invoke_callback(null, ReactNativeBlobUtilConst.RNFB_RESPONSE_PATH, this.destPath, respmap.copy());
@@ -760,7 +760,7 @@ private void done(Response resp) {
                 try {
                     invoke_callback(null, ReactNativeBlobUtilConst.RNFB_RESPONSE_UTF8, new String(resp.body().bytes(), "UTF-8"), respmap.copy());
                 } catch (IOException e) {
-                    invoke_callback("ReactNativeBlobUtil failed to encode response data to UTF8 string.", null);
+                    invoke_callback("ReactNativeBlobUtil failed to encode response data to UTF8 string.", respmap.copy());
                 }
                 break;
         }

fetch.js

@@ -260,6 +260,8 @@ export function fetch(...args: any): Promise {
             promise.cancel = () => {
             };
 
+            if(!responseInfo) responseInfo = {}; // should not be null / undefined
+
             if (err)
                 reject(new Error(err, respInfo));
             else {
@@ -269,9 +271,10 @@ export function fetch(...args: any): Promise {
                     if (options.session)
                         fs.session(options.session).add(data);
                 }
-                respInfo.rnfbEncode = rawType;
                 if ('uninit' in respInfo && respInfo.uninit) // event didn't fire yet so we override it here
                     respInfo = responseInfo;
+
+                respInfo.rnfbEncode = rawType;
                 resolve(new FetchBlobResponse(taskId, respInfo, data));
             }
 

package.json

@@ -1,6 +1,6 @@
 {
     "name": "react-native-blob-util",
-    "version": "0.19.6",
+    "version": "0.19.8",
     "description": "A module provides upload, download, and files access API. Supports file stream read/write for process large files.",
     "main": "index",
     "scripts": {