I am trying to add some external dependency cryptowatch-embed js to my webpack project (of version 1.13.3) as vendor. The concern is that this dependency is written in ES6 style and js file ends with something like export default Embed;. When I run my webpack-dev-server and open the browser the console shows me Uncaught SyntaxError: Unexpected token export on this line. I suppose that webpack does not bundle ES6 vendor properly, but I dot'n have any ideas what should be done to fix this error. So the main question is how can I make webpack work with /node_modules/cryptowatch-embed/src/main.js that is written in ES6?
Related
I am unsure whether I am supposed to use the require version or the import version.
It doesn't state that in the documentation and I found a statement in a Github issue that
Mixing import and require is definitely discouraged. The only way for Rollup to handle require statements is with rollup-plugin-commonjs, but that plugin will skip any files with import or export statements.
which could be interpreted as: "You need to still use require otherwise the common-js plugin will ignore your file and things will not work." or as "always use import everything else would constitute mixing". So that really confused me.
Context
I am trying to import a CommonJS library (Citation-js) into a javascript module (really typescript but I hope this is not relevant here). Now the documentation of common-js tells me to do
const Cite = require('common-js');
which tells me that it is a commonjs library (right?). Therefore I added
import commonjs from "rollup-plugin-commonjs";
import { nodeResolve } from "#rollup/plugin-node-resolve";
to my rollup config and put plugins: [commonjs(), typescript(), nodeResolve()] into the configuration.
Now vscode stops underlining everything and building the website with rollup works again. But the compiled javascript simply states require('common-js') and my browser complains that require is undefined.
Uncaught ReferenceError: require is not defined
So I tried
import Cite from 'common-js';
instead. But that resulted in the rollup build failing with
[!] Error: Unexpected token (Note that you need #rollup/plugin-json to import JSON files)
node_modules/#citation-js/core/package.json (2:8)
1: {
2: "name": "#citation-js/core",
^
Now I could of course install that plugin. But I am not sure that is right, since the whole point of a tool like rollup should be that dependencies of dependencies should be resolved automatically right?
I have also tried
Can't import npm modules in commonjs with rollup : "require is not defined"
This seemed like it would fix my problem: Using Older Require Module With Rollup
But:
the rollup-plugin-node-builtins is apparently not maintained (npm protested with security vulnerabilities and I found this: https://github.com/rollup/rollup/issues/2881). EDIT: There is a new package rollup-plugin-polyfill-node replacing that I guess.
resolve is no longer a member of #rollup/plugin-node-resolve so I assume that this has become nodeResolve which I am already using...
EDIT: installing #rollup/plugin-json actually lets me build the site again (with a bunch of warnings)
(!) Missing shims for Node.js built-ins (which is not fixed by the rollup-plugin-polyfill-node above)
(!) Missing global variable names
(!) Circular dependencies
(!) Unresolved dependencies
not sure what to do about these warnings
I am creating an app with Electron and Vue (using js not ts).
When I run the app using npm run electron:serve the app runs fine.
I now want to build a Windows exe so I can distribute my app. I have tried using electron-builder, electron-packager and electron-forge. Whenever I can get the build to finish, running the exe throws the cannot use import statement outside a module error (referring to the first import statement it finds, i.e. import { app, protocol, BrowserWindow } from 'electron').
I've tried adding "type":"module" to my package.json but (due a bug in Vue, according to this question), that throws Error [ERR_UNSUPPORTED_ESM_URL_SCHEME]
I've also tried changing all my import statements to require but this doesn't work because some of the node modules I'm using use import and the error just throws for those instead.
I'm tearing my hair out over this. Where do I go from here?
UPDATE:
I have found a workaround for the Vue bug and posted my findings on the linked question. I can now add "type":"module" to my package.json.
However, I now get an error thrown when I run npm run electron:serve and from my built exe:
Error [ERR_REQUIRE_ESM]: Must use import to load ES Module: <my_project_root>\dist_electron\index.js
require() of ES modules is not supported.
require() of <my_project_root>\dist_electron\index.js from <my_project_root>\node_modules\electron\dist\resources\default_app.asar\main.js is an ES module file as it is a .js file whose nearest parent package.json contains "type": "module" which defines all .js files in that package scope as ES modules.
To be clear, I'm not using require in any of my source code, but the compiled(?) version does?
What's going on here?
UPDATE 2:
As requested, here is a minimal reproducible example that maintains original folder structure, configs and package.json
How can I run scripts that import css modules?
I'm writing a typescript migration script that I'd like to run via ts-node. Ideally, my codebase would be organized such that the script's dependencies never touch React components, but that's not the case. The script ultimately imports React components and thus css modules, so ts-node fails because it doesn't understand css modules:
RenderableInline.tsx(4,20): error TS2307: Cannot find module './styles/RenderableInline.module.scss' or its corresponding type declarations.
Only webpack understands how to build css modules, since I've configured it via a css-loader.
The only precedent for this I've found is jest, which has some configuration option for mocking out css modules so it can import these files without error: https://jestjs.io/docs/webpack.
How can I run a typescript script that has dependencies on css modules? Is there someway to do this via ts-node? Or does webpack have some script running feature?
Add a global .d.ts file that provides direction on how .css files should be handled.
Such as src/global.d.ts with the following contents:
declare module '*.module.css' {
const classes: { [key: string]: string };
export default classes;
}
May also be helpful to add the typescript-plugin-css-modules plugin. Note though that this only helps during development using VSCode but has no effect during compilation.
While I generally got this working, I am still facing problems to get this to work correctly with ts-node-dev - probably related to ts-node not loading these type files by default Missing Types. Unfortunately even using the --files directive, I couldn't get this to work.
As an exercise I decided to create a little vanilla JavaScript game using ES6 syntax that runs in the browser. The program works fine.
I'd like to test it using Jasmine. However, whenever I try to perform an import e.g.
import Deck from "../Deck.js";
Deck.js starts:
export default class Deck {
I get error SyntaxError: Cannot use import statement outside a module.
Things I've done:
Installed node v13.0.1 - I thought this version of node allowed es6 modules.
Installed jasmine and initialized node ./node_module/jasmine/bin/jasmine init
Run node ./node_module/jasmine/bin/jasmine - works fine without imports
Run node --experimental-modules ./node_module/jasmine/bin/jasmine - doesn't work with imports
Tried require instead of import: const Deck = require('../Deck.js'); - SyntaxError: Unexpected token 'export'
How do I get jasmine to work with imports? At the moment I cannot include any files to test !
I'm sure I've gone about this the wrong way, but i just want some cmd line tests.
Follow the offical guide from Babel at https://babeljs.io/setup#installation
Then choose one of the options from this solution: https://stackoverflow.com/a/59399717/673351
Personally, I have renamed my spec files to have the mjs extension becaue I would like ot use the LTS (currently 12) version of node.
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.