Definitelytyped: ERROR in node_modules/@types/chart.js/index.d.ts - error TS2307: Cannot find module 'moment'

[andreasoikon]

• [x] I tried using the @types/chart.js package and had problems.
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I am using Angular 9.0 with ng2-charts.
I have also installed chart.js

A few days ago I was able to develop my app without problems. Now when I try to run ng serve or ng build I get the error:
ERROR in node_modules/@types/chart.js/index.d.ts:32:24 - error TS2307: Cannot find module 'moment'

I look in the index.d.ts and I see that the import is failing. I also noticed that in my node_modules directory there is a directory called moment. If I type import { Moment } from '../../moment/moment in the @types/chart.js/index.d.ts, everything works. Both ng serve and ng build run successfuly.

I know that correcting node_modules locally is not a good fix because when I send the code to my colleagues via Git it won't have the fix in there. Also, when we deploy to our production servers, npm install will run and as a result a broken version of @types/chart.js will be installed.

I didn't know what is the correct permanent fix so this is why I am submitting an issue and not a pull request.

Thank you in advance,
Andreas

[lekoaf]

If no one else gets back to you I’ll do some research and take a stab at this on monday. Seens odd it would just suddenly break. I’ll go through the commit history.

Do you use moment in your project and / or charts?

[lekoaf]

Could this happen because someone added a test for a time Chart in the latest release? #44275

@adripanico got any idea?

[lekoaf]

I updated to 2.9.20 in my own project like 2 days ago but don’t have any moment issues.

[KentarouTakeda]

This issue is a moment=2.25.0 bug. It seems to be fixed in 2.25.1.

https://github.com/moment/moment/pull/5487#issuecomment-622492292

[andreasoikon]

If no one else gets back to you I’ll do some research and take a stab at this on monday. Seens odd it would just suddenly break. I’ll go through the commit history.

Do you use moment in your project and / or charts?

Hello @lekoaf ,

In my project I only use Radar Chart from ng2-charts version 2.3.0

I don't use moment or chart.js in my project.

As I understand it, ng2-charts depends on chart.js and chart.js imports moment

If it helps my dependencies versions are:

• [email protected]
• chart.[email protected]
• [email protected]
• latest npm version @6.14.4

I went ahead and did some more digging today and I have to report the following. I hope something can give you a hint of what is going on.

1. Simply running npm install in my Angular project, I notice that in node_modules/@types/chart.js/ a node_modules directory inside of which the moment should be, is not created for some reason. The same issue also appears if you run npm install chart.js --save explicitly. TL;DR moment depency is not installed.
2. Also, after running npm install if I open node_modules/@types/chart.js/package.json I notice that bundleDependencies is set to false but in the NPM documentation says that this needs to be an array.
3. Furthermore, regarding moment dependency in package.json, I see that the version is "moment": "^2.10.2" and not 2.25.1 as @KentarouTakeda says.
4. If I put somehow a node_modules/moment in the node_modules/@types/chart.js/ directory everything works. The final structure would be node_modules/@types/chart.js/node_modules/moment.

Waiting on your help. Thank you in advance

[andreasoikon]

Update

Today my app magically worked. I did some digging around my node_modules directory and it seems that moment updated itself to 2.25.1

So @KentarouTakeda message seems to be correct.

The problem for me was that I didn't and I don't use moment anywhere so the dependency gets install by some other dependency of mine and I couldn't be sure if it was chart.js or another dependency.

Anyway, but to normal. Thank you again @lekoaf and @KentarouTakeda