Syntax error: Cannot read property 'map' of undefined (0:undefined) build on aws amplify

Question

I am facing the following error while building on AWS amplify:

Syntax error: Cannot read property 'map' of undefined (0:undefined)

Here is my code:

import React from 'react';   
import ReactDOM from 'react-dom'; 
export default class BusinessHTTPService {
static getBusinessList = () => {
  
    return axios.get(`${API_BASE}business-categories/?`).then(response => response.data);
  };
  
  }

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>

While I am building code on AWS it's throwing an error but locally when I am running the code its working fine. — Harish, Aug 29 '20 at 09:30
Does this answer your question? [Line 0: Parsing error: Cannot read property 'map' of undefined](https://stackoverflow.com/questions/62079477/line-0-parsing-error-cannot-read-property-map-of-undefined) — smac89, Jul 06 '21 at 20:37

score 5 · Answer 1 · edited Sep 10 '20 at 13:23

5

I had the same issue with by build failing on AWS Amplify Console, but was fine locally.

How to reproduce locally

I was able to reproduce it locally by following these steps:

run "npm ci"
run "npm start"

"npm start" would fail, and show the error "Line 0: Parsing error: Cannot read property 'map' of undefined".

How to solve

I was able to solve it eventually by following these steps:

downgrade typescript from version 4.0.2 to version 3.9.7.
run "npm ci"
run "npm start"

I don't see the error anymore, and when I push to AWS Amplify Console, it builds without issues.

edited Sep 10 '20 at 13:23

Dharman

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answered Sep 10 '20 at 13:18

Enrico Pangan

76
2

This helped me even though I don't use AWS Amplify. There appears to be something wrong in the TS compiler and babel/webpack. – Francis Upton IV Sep 29 '20 at 16:03

score 0 · Answer 2 · answered Mar 25 '21 at 08:14

0

I had similar issue with this code:

interface Event<EventArgs extends unknown[] = []> { ... }

The problem disappeared when I specified the type of the array:

interface Event<EventArgs extends unknown[] = unknown[]> { ... }

answered Mar 25 '21 at 08:14

Monsignor

2,671
1
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Syntax error: Cannot read property 'map' of undefined (0:undefined) build on aws amplify

2 Answers2