TypeError: Cannot read property 'substr' of undefined - source-node.js

Question

This error comes as a result of resolving this question

Here is my ionic info:

Cordova CLI: 6.5.0
Ionic Framework Version: 2.0.0
Ionic CLI Version: 2.2.1
Ionic App Lib Version: 2.2.0
Ionic App Scripts Version: 1.0.0
ios-deploy version: Not installed
ios-sim version: Not installed
OS: Windows 10
Node Version: v7.4.0
Xcode version: Not installed

(I am also using npm v4.1.1)

When attempting to build @ionic/app-scripts, I am getting the following error:

E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\node_modules\source-map\lib\source-node.js:95
      var code = nextLine.substr(0, mapping.generatedColumn -
                         ^

TypeError: Cannot read property 'substr' of undefined
    at Function.<anonymous> (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\node_modules\source-map\lib\source-node.js:95:30)
    at Array.forEach (native)
    at BasicSourceMapConsumer.SourceMapConsumer_eachMapping [as eachMapping] (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\node_modules\source-map\lib\source-map-consumer.js:155:14)
    at Function.SourceNode_fromStringWithSourceMap [as fromStringWithSourceMap] (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\node_modules\source-map\lib\source-node.js:80:24)
    at SourceMapSource.node (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\lib\SourceMapSource.js:42:20)
    at ReplaceSource.node (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\lib\ReplaceSource.js:69:29)
    at CachedSource.node (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\lib\CachedSource.js:12:23)
    at E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\lib\ConcatSource.js:40:49
    at Array.map (native)
    at ConcatSource.node (E:\Documents\Year_3\Mobile_Application_Development\mammoth-v2\node_modules\webpack-sources\lib\ConcatSource.js:39:60)

If needed, when I run npm run build (to build @ionic/app-scripts), this is the build log:

[07:28:45]  ionic-app-scripts 1.0.0 
[07:28:45]  build dev started ...
[07:28:45]  clean started ...
[07:28:45]  clean finished in 4 ms
[07:28:45]  copy started ...
[07:28:45]  transpile started ...
[07:28:49]  transpile finished in 4.44 s
[07:28:49]  webpack started ...
[07:28:49]  copy finished in 4.57 s

            **errors arise here**

EDIT:

I added the configuration:

"config": {
    "ionic_generate_source_map": false
},

...to packages.json which seemed to fix the error but am now faced with another one:

Error: ENOENT: no such file or directory, open 'main.js.map'

Which is thrown when I attempt to do ionic serve (the build of @ionic/app-scripts works just fine now)

EDIT #2:

Does ionic rely on a source map to run? As the error is arising because non are built

Answer 1

This error comes from having two 2 classes/components in one ts file.

A brutal way to fix this.

Is going to node_modules\webpack-sources\node_modules\source-map\lib\source-map\source-node.js

And exchanging all 2 times this appears:

var nextLine = remainingLines[0];

To this

var nextLine = remainingLines[0] || '';

Problem with this solution is that you can't put it into version control since this is node modules