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Yarn and wasm module linking does not work due to yarn caching

I have a very simple app here where index.html simply imports index.js where:
index.js
import * as wasm from "wasm";
wasm.greet();
lib.rs
mod utils;
use wasm_bindgen::prelude::*;
#[cfg(feature = "wee_alloc")]
#[global_allocator]
static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
#[wasm_bindgen]
extern { fn alert(s: &str); }
#[wasm_bindgen]
pub fn greet() { alert("Wasm is running haha!"); }
package.json
...
"dependencies": {
"wasm": "portal:../pkg"
},
...
Now, here is my issue:
When I use "file:../pkg" in package.json, everything works, but if
I make a change and recompile using wasm-pack it does not update.
Even running yarn install will not update. The only way I can get
changes to show is by running yarn install --check-files but then
the install takes time and it's quite painful.
When I use "portal:../pkg" in package.json instead, I get an error ERROR in ./index.js Module not found: Error: Can't resolve "wasm" ..... This is not what I expect.
When I use "link:../pkg" everything works as planned, and I do not have to run yarn install every-time I compile to see the changes. This is great and what I really want.
Yet, when I read protocols here https://yarnpkg.com/features/protocols the difference between link and portal is only that portal will follow dependencies if package.json exists in my ../pkg folder. In my case, it does, and I expect to have further dependencies there. So how can I get portal to work? And why is it not working now when link is working?

npm package contains more than one file - how to umport these

I've a npm package with the following three files in the dist folder (generated by webpack):
Inside the package.json file I've declated the sample.js file as the main one: "main": "dist/sample.js",.
Now I wan't to use this package in another project. Did I need to import all three files? Or should all work fine with one import like import aFunction from 'package-name'?

If there aren't any other weird dependencies, and sample.js is actually the entrypoint of the library (i.e. either you do everything inside it, or you make all the needed exports from it), it should work fine just as you wrote, i.e. import aFunction from 'package-name'.
Btw, is sample.js minified? As far as I remember, starting with Webpack v4 it does the minification automatically for production builds. But you might still want to doublecheck (read here for more info).

Vue JS Module not found (datepicker)

I am pretty new to vue.js - I only started using it today and naturally I have run into an error I cannot seem to resolve.
I am using the v-md-date-range-picker module:
(https://ly525.github.io/material-vue-daterange-picker/#quick-start.
The instructions tell me to do the following:
1
npm install --save v-md-date-range-picker
2
<template>
<v-md-date-range-picker></v-md-date-range-picker>
</template>
3
<script>
import Vue from 'vue';
import VMdDateRangePicker from "v-md-date-range-picker";
import "v-md-date-range-picker/dist/v-md-date-range-picker.css";
Vue.use(VMdDateRangePicker);
</script>
So, I ran the command in terminal in my project folder, added the 2 bit of code to my HelloWorld.vue page and then added the code from step 3 into the main.js.
When I have a look in my package.json file, I see:
"dependencies": {
"core-js": "^2.6.5",
"v-md-date-range-picker": "^2.6.0",
"vue": "^2.6.10"
},
However, I get the error:
Module not found: Error: Can't resolve 'v-md-date-range-picker/dist/v-md-date-range-picker.css' in '/Users/James/Documents/projects/vue-test/src'
am I missing something blatantly obvious here?
Edit:
I tried the response in the comments below which did not work.
On the main page of the module, I followed the instructions. However, going through the pages I found the same instructions with some extra text:
I assume that you have a working bundler setup e.g. generated by the vue-cli thats capable of loading SASS stylesheets and Vue.js SFC (Single File Components).
I am going to go out on a limb here and say I do not have a working bundler. I went into the node_modules folder, found that module and looked inside. There was no dist folder. Just .scss files etc..
So, I assume that I somehow need to build this project first.
How do I do that?
I thought running it in the browser would have done this on the fly but it clearly has not.
Edit 2:
After some googling around I found the command:
$ npm run build.
Which gives me this error:
This dependency is not found, To install it, you can run: npm install --save v-md-date-range-picker/dist/v-md-date-range-picker.css
So, I run that command and then I get the error:
Could not install from "v-md-date-range-picker/dist/v-md-date-range-picker.css" as it does not contain a package.json file.

Check if you can find this in the webpack.base.conf.js inside the build folder. If not add it.
module: {
rules: [
{
test: /\.css$/,
loader: ['style-loader', 'css-loader'], // Note that the order is very important
},
Run npm install style-loader css-loader --save before adding it to the file if it isn't there.
To Address your question
Run the command: npm install sass-loader --save
Then add an import for every SCSS file in the module.
This is not the most optimal solution, but that package looks broken to me and this is merely a workaround.
I will take time to try out the library myself and try to provide a fix for it.

Create v-md-date-range-picker.css in v-md-date-range-picker/dist/ and copy css from
md-date-range-picker.min.css
and refresh your page. For some reason css file is not being created when we install md-date-range-picker.min

How can I resolve the following compilation error when running Jest for testing?

Although I am able to start the npm project using npm start without any issues with webpack or babel, once I run npm test, I find the following error related to testing App.js using App.test.js (where App.js imports ApolloClient):
TypeError: Cannot assign to read only property '__esModule' of object '[object Object]'
| import ApolloClient from 'apollo-boost';
| ^
at node_modules/apollo-boost/lib/bundle.cjs.js:127:74
at Array.forEach (<anonymous>)
at Object.<anonymous> (node_modules/apollo-boost/lib/bundle.cjs.js:127:36)
Essentially, I'm confused as to why I get an error when running the test but not when starting the project.
I've tried adding in a number of babel plugins to both .babelrc and in my webpack config file:
#babel/plugin-transform-object-assign
#babel/plugin-transform-modules-commonjs
babel-plugin-transform-es2015-modules-commonjs
However, I haven't been able to resolve the issue. My thinking was that this is related to the fact that the file that fails to compile was originally CommonJS.
I was only able to find something relatively similar here, https://github.com/ReactTraining/react-router/pull/6758, but I didn't find a solution.
Is there something that I'm missing specifically related to running tests? I should also mention I've tried frameworks other than Jest and ran into the same issue.
EDIT:
I removed everything from App.test.js except the imports to isolate the issue so it just contains the following:
import React from 'react';
import { shallow } from 'enzyme/build';
import App from './App';
UPDATE:
I was able to resolve the initial error by upgrading apollo-boost from version 0.3.1 to 0.4.2. However, I now have a different error that is similarly frustrating. I am using Babel 7 and have added the plugin #babel/plugin-syntax-dynamic-import to both my .babelrc and to my webpack.config.js files. Despite this, I get the following error related to the use of a dynamic import in App.js when running the Jest to test App.test.js:
SyntaxError: Support for the experimental syntax 'dynamicImport' isn't currently enabled
Add #babel/plugin-syntax-dynamic-import (https://git.io/vb4Sv) to the 'plugins' section of your Babel config to enable parsing.
I'm not sure if there is a parsing error or something else, but I've tried numerous things that have not worked. The closest discussion I could find related to this problem is, https://github.com/facebook/jest/issues/5920, however, the proposed solutions don't work for me.
UPDATE:
One thing that I'm trying is to avoid duplication of the babel options as right now they're both in .babelrc and in the babel-loader options within webpack.config.js. From what I found online (Whats the difference when configuring webpack babel-loader vs configuring it within package.json?), the way to make webpack use the settings in .babelrc is to not specify options. However, doing so results in the same error described above showing up only this time when running npm start. I will add that the project that was originally created using create-react-app, however, in order to support multiple pages, I needed to customize webpack's configuration and so ejected from it. I'm not sure why this is so convoluted.

its probably a babel configuration issue, I'm pretty sure jest needs to be compiled to work with create-react-app...
did you specify a setup file in package.json:
"jest": {
"setupFiles": [
"/setupTests.js"
]
}
and in setupTests.js:
import { configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';
configure({ adapter: new Adapter() });

It turns out that one of the components in the project's src directory had its own local package.json file even though it wasn't being used and was not installed as a local dependency in the top level package.json (instead imports were done using relative urls). For some reason, the existence of this file changed the behavior of webpack and other tools when starting and testing the project such that none of the top level configurations were used for files within directories with separate package.json files. Once I removed these local package.json files from the components sub-directory, all the prior issues were resolved. One hallmark of this problem is that compilation errors were not showing up for JavaScript files that weren't nested under an alternate package.json file.
Hopefully this is useful for anyone that encounters similar errors as I don't think the cause can be directly determined from the compiler messages alone.

Flow: Throws error Cannot resolve module "react-redux" even tho it's installed

Even tho module is installed and it exists, Flow cannot resolve it and throws error.
See below:
1) Inside bash I ran flow and it throws error that module is not found
user#pc:~/code/project$ flow
Error ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ src/functionalities/Growth/index.js:3:25
Cannot resolve module react-redux.
1│ // #flow
2│ import React from "react"
3│ import { connect } from "react-redux"
4│
5│ type Props = {
6│ children: Function
Found 1 error
2) Below command checks whether directory exists and it does
user#pc:~/code/project$ ls node_modules | grep react-redux
react-redux
I tried to remove and reinstall both node_modules directory and yarn.lock file.
Versions should be matching:
flow version
Flow, a static type checker for JavaScript, version 0.77.0
.flowconfig:
[version]
0.77.0
This is very likely bug with Flow, I also submitted issue.

How to fix it
You have two options:
stub the dependency by hand
bring in flow-typed to find the dependency type
file/stub it for you
I use option 2 but it is nice to know what is happening underneath
Option 1
In .flowconfig, add a directory under [libs],
...
[libs]
/type-def-libs
...
Now, create that directory at your project root and a file /type-def-libs/react-redux which contains,
declare module 'react-redux' {
declare module.exports: any;
}
Option 2
install flow-typed, if using yarn yarn add -D flow-typed
I prefer to install every locally to the project when possible
run yarn flow-typed install
this will install any type definition files for modules that it finds AND it will stub any modules it doesn't find, which is similar to what we did in option 1
Why is this error happening
Flow is looking for the type definition for the module you are importing. So while the module does exist in /node_modules that module doesn't have a type definition file checked into its code.

I had the same issue as you.
I resolved it by using flow-typed
I did the following:
Install flow-typed globally. example: $ npm install -g flow-typed
Then inside your project root folder, run $ flow-typed install react-redux#5.0.x
• Searching for 1 libdefs...
• flow-typed cache not found, fetching from GitHub...
• Installing 1 libDefs...
• react-redux_v5.x.x.js
└> ./flow-typed/npm/react-redux_v5.x.x.js
react-redux
You should see this if the install was successful.
Then try running flow again $ npm run flow in your project. The error with react-redux will no longer be there.

Alternative solution (for some cases)
Check your .flowconfig and remove <PROJECT_ROOT>/node_modules/.* under the field [ignore] (in case you have it there).
UPDATE 1 (by arka):
Or you can add !<PROJECT_ROOT>/node_modules/react-redux/.* after <PROJECT_ROOT>/node_modules/.*. This will ignore all the modules except for react-redux.
Thanks to #meloseven who solved it here.

I checked my package.json file and noticed react-redux was missing. I manually added it to the dependencies "react-redux": "x.x.x" and ran npm install thereafter. Note that the version number should be compatible with the other modules.

Please ensure that you provide the path under 'ignore' in .flowconfig, like this:
[ignore]
.*/node_modules/react-native/Libraries/.*
and not like this:
.*/node_modules/react-native/Libraries/Components
.*/node_modules/react-native/Libraries/Core
....