node.jsangulartypescriptnpmdate-fns

Why if I try to use the node.js module 'date-fns' I get the TypeScript compilation error TS1005?

I'm trying to use the format function of the Node.js module date-fns.

Some info about my system (obtained by the command ng --version) is reported below:

Angular CLI: 13.2.0
Node: 16.13.2
Package Manager: npm 8.6.0
OS: linux x64

I have installed date-fns by the command:

npm install date-fns

I have written an example file test_typescript.ts with the following code:

import { format } from 'date-fns';

const currentDate: Date = new Date();
const formattedDate: string = format(currentDate, 'dd/MM/yyyy HH:mm');
console.log(formattedDate);

If I try to compile it by the following command:

tsc src/test_typescript.ts

I obtain the following error TS1005:

node_modules/date-fns/clamp.d.ts:18:59 - error TS1005: '?' expected.
18   Options extends ClampOptions<infer DateType extends Date>
                                                             ~

node_modules/date-fns/closestTo.d.ts:18:63 - error TS1005: '?' expected.
18   Options extends ClosestToOptions<infer DateType extends Date>
                                                                 ~

node_modules/date-fns/interval.d.ts:21:62 - error TS1005: '?' expected.
21   Options extends IntervalOptions<infer DateType extends Date>
                                                                ~
Found 3 errors.

The problem is in the import. How can I solve it?

Solution

  • The TypeScript version is too old for the date-fns version

    Thanks to @jonrsharpe (see the comments to the question) I have solved my problem which is a compatibility conflict between the version of the module date-fns and the version of the TypeScript compiler installed on my system.

    In particular the TypeScript compiler version 4.5.5 doesn't support the version 4.1.0 of date-fns (this is the date-fns version released until today and this version has been installed by default by the command npm install date-fns).

    This is highlighted by the jonrsharpe's comment:

    Looks like you need TS v5 to use date-fns v4 ...

    So I have removed the installed module by the command:

    npm uninstall date-fns

    Downgrade date-fns to version 2.30.0

    After that I have followed some of the steps described in this post.
    The first step is to get the list of date-fns versions available by the following command:

    npm view date-fns versions

    In the list there are many versions so by many downgrade attempts, which led me to other compilation errors, I have found that the newest version compliant with my TypeScript compiler (version 4.5.5) is the date-fns version 2.30.0.

    So I have installed it by the command:

    npm install date-fns@2.30.0

    Compilation and execution of my script

    After this downgrade I have been able to compile and execute my test file:

    # compilation
tsc src/test_typescript.ts

# execution
node src/test_typescript.js

# output
23/10/2024 17:41