Develop Reference

Use jest to test a not exported object in an imported script with webpack 5

The title may seems a bit confusing, let me explain.
I'm using an opensource library pico which has a not exported object "pico", so I put ?raw keyword to import it in my frontend project with webpack 5.
import "./lib/pico.js?raw";
And it works properly on my frontend page.
--
Then when I want to unit test it by jest, I found jest-raw-loader by this post, but the pico seems won't be imported by using this library.
The ?raw on webpack seems more similar as script-loader library.
And jest-raw-loader seems more similar as raw-loader on older versions.
Although webpack official doc suggest to replace raw-loader with ?raw, but they seem different in my case.
I know I can simply edit this pico.js file to export this object. But what if next time I have a far larger library need to be managed? Is there any other way to import this kind of "not exported" object?

How to use npm packages as ES6 modules loaded by the browser in 2021?

I'm a JavaScript beginner. I do not use a "bundler".
For a few days now I've been trying to use moment.js and other date-time libraries in some JavaScript by importing it using ES6 modules (ESM).
I have a JS module I wrote, which is transpiled from TS, and that has this line:
import moment from "../lib/moment/src/moment.js"
My module is itself loaded via an import from a <script type="module" > tag, which works.
I've discovered that the moment package contains what looks like "source" code in its src folder which seems to look more like the JS/TS I'm accustomed to, and has a "default export" at the bottom.
So I'm referencing that "source" version in my transpiled JS module. This gets me past a couple of errors I was getting:
The requested module 'blah' does not provide an export named 'default'
And
Cannot set property 'moment' of undefined (at moment.js:10)
And leaves me stuck with loading the other modules its dependent upon, because I guess, their file extensions are missing.
GET https://blah/lib/moment/src/lib/locale/locale net::ERR_ABORTED 404 (moment.js:37)
After 3 days tearing my hair out I feel like I have been fighting a battle I shouldn't be attempting at all.
I would expect in 2021, what with widespread ESM browser support, that this would just work, but I've tried 5 different date-time libraries and had no success.
I assume the 404s have occurred because the moment authors are NOT expecting people to be using their library like this, so they left off the file extensions knowing full well that it wouldn't load in a browser??
Am I supposed to add an extra step in my client-side build process, Gulp, to add the extensions back on in the moment source code??
Or am I doing something else wrong?
Is it perhaps that everyone uses a "bundler" and these tools fix all this stuff somehow and so these issues never arise for 99% of web devs??
Thanks in advance.

You want to import a bundled version of the lib to be able to do that. Try:
import from 'https://unpkg.com/moment#2.29.1/dist/moment.js' ;
You can download the bundled version and add to your project. Don't forget to put the license as well and check if they are at least MIT or similar.
If you want to refer to the source code you will certainly need to build that. Specifically with libs that are using typescript.

working 'types' definition files, anyone?

We're using Tabulator-tables in a large Angular project and I cannot seem to find a usable definition files.
I've tried https://www.npmjs.com/package/#types/tabulator-tables which seems updated etc but it results in lots of errors in my IDE and the project will not compile as a result. There are many errors even though the compilation worked before I added the types package. Its pointless and impractical to add many #ts-ignore comments.
Be advised - I took notice to use the same version of the type definition package as installed in my project (v4.2.2). I assume the problem is with the automatic generation of the above package - the resulting .d.ts file is not usable as a result.
Please correct me if I'm wrong and any help in integrating definition files will be appreciated. TIA!

I had a similar issue with adding TypeScript typings on Angular project and here's what i did:
encapsulated Tabulator inside Angular component (data-grid.component.ts in my case);
npm install #types/tabulator-tables
created file data-grid.component.d.ts with:
declare module 'tabulator-tables' {
export = Tabulator;
}
the key thing: removed import Tabulator from 'tabulator-tables' from file data-grid.component.ts
And it's worked.

A full set of TypeScript Typings can be found in the #types/tabulator-tables npm package
npm install #types/tabulator-tables
An example of how to use the typings in a project can be found here
The Language Documentation includes more information on the available typings

I already wrote an answer for this issue, not good enough in my opinion, but some people upvoted it as right, so I decided to leave it as it is and write a new one.
There is some issues with adding types for tabulator, this is because type annotations not being exported, but there is a way to use them.
After installation of types for tabulator (npm install --save #types/tabulator-tables), you should open (or create it, if it's not exists) file index.d.ts inside directory src, and copy following code into it:
declare module 'tabulator-tables' {
export = Tabulator;
}
You need to ensure that you have "allowSyntheticDefaultImports": true inside compilerOptions of file tsconfig.json or tsconfig.app.json (depends on your project), and tsconfig.spec.ts (it needs for unit testing).
Very important to unload and start over ng serve after editing of tsconfig.
After that all typings should work. Just in case I created simple Angular example, hope this helps.

Ember why do we have to use import for certain bower dependencies

In an Ember app, when using certain dependencies like moment installed via bower, we have to also import the same in the ember-cli-build.js file:
app.import('bower_components/moment/moment.js');
My question is why is that needed, since I would assume everything inside node_modules as well as bower_components should be available for use inside the app.
Also if that is not the case, how do we identify which dependencies would require such explicit import to be able to use them ?

You don't have to, actually.
There is a package now that lets you 'just import' things: https://github.com/ef4/ember-auto-import
Some reading on the topic of importing: https://discuss.emberjs.com/t/readers-questions-how-far-are-we-from-being-able-to-just-use-any-npm-package-via-the-import-statement/14462?u=nullvoxpopuli
In in-depth answer to your question and the reasons behind why things are the way they are is posted here:
https://discuss.emberjs.com/t/readers-questions-why-does-ember-use-broccoli-and-how-is-it-different-from-webpack-rollup-parcel/15384?u=nullvoxpopuli
(A bit too long for stack overflow, also on mobile, and I wouldn't want to lose all the links and references in a copy-paste)
Hope this helps
Edit:
To answer:
I just wanted to understand "in what cases" do we need to use the import statement in our ember-cli-build (meaning we do not do import for all the dependencies we have in our package/bower.json)...But only for specific ones...I wanted to know what is the criteria or use case for doing import.
Generally, for every package, hence the appeal of the auto-import and / or packagers (where webpack may be used instead of rollup in the future).
Though, it's common for ember-addons to define their own app.import so that you don't need to configure it, like any of these shims, specifically, here is how the c3 charting library is shimmed: https://github.com/mike-north/ember-c3-shim/blob/master/index.js#L7
Importing everything 'manually' like this is a bit of a nuisance, but it is, in part, due to the fact that js packages do not have a consistent distribution format. There is umd, amd, cjs, es6, etc.
with the rollup and broccoli combo, we need to manually specify which format a file is. There are some big advantages to the rollup + broccoli approach, which can be demonstrated here
and here
Sometimes, depending on the transform, you'll need a "vendor-shim".
These are handy when a module has decided it wants to be available on the window / global object instead of available as a module export.
Link: https://simplabs.com/blog/2017/02/13/npm-libs-in-ember-cli.html
(self represents window/global)
however, webpack has already done the work of figuring out how to detect what format a js file is in, and abstracts all of that away from you. webpack is what ember-auto-import uses, and is what allows you to simply
import { stuff} from 'package-name';. The downside to webpack is that you can't pipeline your transforms (which most people may not need, but it can be handy if you're doing Typescript -> Babel -> es5).

Actually: (almost) everything!
Ember does, by default, not add anything to your app except ember addons. There are however some addons that dynamically add stuff to your app like ember-browserify or ember-auto-import.
Also just because you do app.import this does not mean you can use the code with import ... from 'my-package'. The one thing app.import does is it adds the specified file to your vendor.js file. Noting else.
How you use this dependency depends completely on the provided JS file! Ember uses loader.js, an AMD module loader. So if the JS file you app.imported uses AMD (or UMD) this will work and you can import Foo from 'my-package'. (Because this is actually transpiled to AMD imports)
If the provided JS file provides a global you can just use the global.
However there is also the concept of vendor-shims.. Thats basically just a tiny AMD module you can write to export the global as AMD module.
However there are a lot of ember addons that add stuff to your app. For example things like ember-cli-moment-shim just exist to automagically add a dependency to your project. However how it's done completely depends on the addon.
So the rule is:
If its an ember addon read the addon docs but usually you shouldn't app.import
In every other case you manually need to use the library either by app.import or manual broccoli transforms.
The only exception is if you use an addon that tries to generically add dependencies to your project like ember-browserify or ember-auto-import

Attempting to load a JavaScript sdk into an Angular2 application. Can't find all dependencies

I'm attempting to make use of this library: https://github.com/MagicTheGathering/mtg-sdk-javascript in an Angular2 application.
Unfortunately, I've been going in circles trying to load it into my application.
Firstly, on the TypeScript side if I import it using:
import { } from 'mtgsdk';
there are no types to load into the {}.
If I attempt to load it using something similar to:
import * as mtg from 'mtgsdk'
I'm unable to because it says that it's unable to find a module named mtgsdk.
I've installed the module using
npm install --save mtgsdk
Also, npm installs work fine for other modules.
The application compiles fine if I load it in using require via something similar to this:
var mtg = require('mtgsdk');
Taking that approach, I'm able to compile and launch but in the browser I get a number of errors about modules that it can't find. I figure they are prerequisites for the sdk that didn't get loaded so I start bringing them in via package.json.
For every one that I bring in, I then have to go to systemjs.config.js and add an entry pointing to the module's entry point and often have to specify a default extension using blocks like this:
pointer
'mtgsdk': 'npm:mtgsdk/lib/index.js',
'request-promise': 'npm:request-promise/lib/rp.js',
'ramda': 'npm:ramda/dist/ramda.js',
'emitter20': 'npm:emitter20/index.js',
'bluebird': 'npm:bluebird/js/browser/bluebird.js',
'request': 'npm:request/index.js'
default extension
'request-promise':
{
defaultExtension: 'js'
}
I'm not sure if that's the right approach though because the more dependencies I add, the more that I end up requiring. At one point I had literally gotten up to 50 extra dependencies added because every time I launched, the browser console would find more that were needed.
Is there any easier way to load all of these in?
Also, some of them (such as tough-cookie and request-promise-core) were very problematic to load and I couldn't get the browser console to stop complaining about them. Finally, some of them seemed very basic such as url, http, https. Those seem like they should already be present.

Using systemjs was utilized in the previous versions of Angular 2, However Angular 2 has evolved to Angular 4, with super new features like Angular CLI.
I recommend your use Angular CLI, with #angular/cli.
Importing Node modules
Since mtgsdk is a node-module, you can easily import it using
import * as mtg from 'mtgsdk'
However for your program to compile, you must install a type definition for it. or declare one for it in /typings.json or your app might not build.
Importing Client Scripts
For client scripts like firebase.js you won't need to add client scripts as entries in systemjs.config.js again.
Using #angular/cli, you would easily add them in the scripts[] array in your angular-cli.json for automatic compilation.
Then access them like this
declare const firebase: any;
Here is a quickstart tutorial to set up Angular with #angular/cli.