I am using Parcel to bundle my Javascript files. Everything works fine when using the localhost server to test out the build, however in production it doesn't like dynamic imports.
Here is the code snippet that I am importing:
if (condition) {
await import('./components/modify_root.js');
} else {
await import('./components/index_root.js');
}
My exact error is this. The app.js error is pointing to the second line in the code snippet.
The libraries I am using are PreactJS for frontend framework and node-sass for CSS.
Related
I'm converting a project that was built using Create React App to use ParcelJS as a bundler instead. Strangely, a dependency that I imported during development (#twilio/voice-sdk) works fine in the CRA version of the application, but I get the following error when I try to invoke the constructor in the Parcel version:
TypeError: (this._options.AudioHelper || audiohelper_1.default) is not a constructor
The package is identical between both (#v2.1.1, the latest). I'm importing using ESM syntax, so:
import { Device } from '#twilio/voice-sdk'
I trying using CommonJS syntax (require) and it still didn't work. I've dug into the compiled code, and that seems to be the issue. I imagine there are a lot of differences, but one that I've noticed is here:
On the left is the code compiled by Create React App, which does seem to be exporting something more substantial than on the left - is the export just an empty object? If so, it's no wonder I'm getting a constructor error.
Unfortunately, no amount of googling and SO sleuthing has clarified what I could do to make ParcelJS transpile this dependency properly, if that's the issue. I've tried to make the babel config for ParcelJS match CRA more closely by adding the following to a babel.config.json
{
"plugins": [
"#babel/plugin-transform-modules-commonjs"
]
}
But no luck. Any ideas from where to go from here, or is it time to switch to Webpack?
It looks like Twilio package has a problem when using Parcel 2: https://github.com/twilio/twilio-voice.js/issues/101
I've created a vue3 cli project with Mocha testing:
vue create vue_proj_with_mocha_testing
(accept defaults)
cd vue_proj_with_mocha_testing
vue add unit-mocha
Then in Visual Code I install the Mocha Test Explorer extension, restart, add the folder to the workspace, click the folder, ctrl-shift-p and Mocha Test Explorer : "Enable for a workspace folder". Out of the box Mocha Test Explorer doesn't seem to like vuecli's example.spec.js test:
import { expect } from 'chai'
import { shallowMount } from '#vue/test-utils'
import HelloWorld from '#/components/HelloWorld.vue'
describe('HelloWorld.vue', () => {
it('renders props.msg when passed', () => {
const msg = 'new message'
const wrapper = shallowMount(HelloWorld, {
propsData: { msg }
})
expect(wrapper.text()).to.include(msg)
})
})
I add this entry to settings.json so that Test Explorer finds the vue "tests" folder, which is different from the default of "test".
"mochaExplorer.files": ["tests/**/*.spec.js"],
And then receive this error in Test Explorer:
import { expect } from 'chai';
^^^^^^
SyntaxError: Cannot use import statement outside a module
This indicates I have some transpiling work to do, and Mocha Test Explorer indicates the way to do that is the "mochaTestExplorer" fields in settings.json, but I'm not sure what combination of babel packages would be required. What should be done to run this out-of-the-box vue-cli-3 test in Mocha Test Explorer in Visual Studio Code? Here is my current guess:
"mochaExplorer.require": [
"#babel/preset-env",
"#babel/register",
"#babel/polyfill",
"#babel/plugin-transform-runtime"
],
First, add #babel/register in yours devDependencies.
After, add in your Visual Studio Code settings.json:
"mochaExplorer.files": "tests/**/*.spec.js",
"mochaExplorer.env": {
"NODE_ENV": "test"
},
"mochaExplorer.require": [
"#babel/register"
]
Finally, changes your babel.config.js to like this:
const presets = [];
if (process.env.NODE_ENV === 'test') presets.push('#babel/preset-env');
else presets.push('#vue/cli-plugin-babel/preset');
module.exports = {
presets,
};
I'm afraid what you want is not possible - problem is it is not enough to setup Babel correctly. Vue single file components (.vue) need to be processed by Vue Loader which is Webpack loader plugin.
And there is no easy way how to setup Mocha Test Explorer to use webpack as indicated by the author himself in this thread - Support for vue cli projects
So I decided to split my tests into two groups, tests/ui (tests using Vue components) and tests/unit (non-ui tests) and use setup described by Fernando with these modifications:
Configure Mocha Test Explorer to only search for non-ui tests:
"mochaExplorer.files": "tests/unit/**/*.spec.js",
package.json:
"test:unit": "vue-cli-service test:unit tests/unit/**/*.spec.js tests/ui/**/*.spec.js",
...to include both folders when running tests from command-line
Note: Last step - modifying babel.config.js - is not needed, everything works fine without it....
On a slightly different config, i worked for me: in .vscode/settings.json
{
"mochaExplorer.require": "esm"
}
esm should also be in your dev dependencies
I'm working on a just created Vue cli project with TypeScript and unit testing.
I Know that Vue cli tests uses mocha-webpack to runt tests. And when I Type mocha-webpack on terminal, the tests runs ok.
But I would like to use an mocha-test-explorer, a VS Code extension for mocha testing. For a better programming experience.
I Installed the extension and configured like this:
"mochaExplorer.files": "tests/**/*.ts",
"mochaExplorer.require": "ts-node/register"
But I'm still not able to see the tests. test-explorer shows the fallowing output:
(function (exports, require, module, __filename, __dirname) { import { expect } from 'chai'
^^^^^^
SyntaxError: Unexpected token import
I know that is because mocha is not loading files through webpack.
What should I do to see mocha-webpack tests in the mocha-test-explorer extension (or any other gui extension) for VSCode?
I'm having issues getting PostgreSQL to run on my local machine with react-native. I work primarily as a database developer so it's possible I'm missing something, but in my opinion this is something that should be well documented.
I run the following commands to create a react native project (npm v 4.6.1)
npm install -g expo cli
expo init needhelp
cd needhelp
then I paste in my app.js file and it runs fine. This is my app.js file.
import React, { Component } from 'react';
import { Text, View, Image } from 'react-native';
//const { Client } = require('pg')
//const { Pool, Client } = require('pg')
export default class HelloWorldApp extends Component {
render() {
return (
<View style = {{flex: 1, flexDirection: 'column', alignItems: 'center',}}>
<Text>Hello World!</Text>
</View>
);
}
}
The problem is, when I try and include pg in any way I get errors. The first error I get is "unable to resolve module pg." Then after I run npm install pg, I get
[22:32:20] The package at "node_modules\pg\lib\index.js" attempted to import the Node standard library module "util". It failed because React Native does not include the Node standard library. Read more at https://docs.expo.io/versions/latest/introduction/faq.html#can-i-use-nodejs-packages-with-expo
[22:32:20] Failed building JavaScript bundle.
Then after installing this I get:
[22:34:03] The package at "node_modules\pg\lib\connection.js" attempted to import the Node standard library module "net". It failed because React Native does not include the Node standard library. Read more at https://docs.expo.io/versions/latest/introduction/faq.html#can-i-use-nodejs-packages-with-expo
[22:34:03] Failed building JavaScript bundle.
Building JavaScript bundle [===================================================================================== ] 9>
Then
[2:36:57] The package at "node_modules\pg\lib\client.js" attempted to import the Node standard library module "events". It failed because React Native does not include the Node standard library. Read more at https://docs.expo.io/versions/latest/introduction/faq.html#can-i-use-nodejs-packages-with-expo
[22:36:57] Failed building JavaScript bundle.
then
[00:38:48] The package at "node_modules\pg\lib\connection.js" attempted to import the Node standard library module "tls". It failed because React Native does not include the Node standard library. Read more at https://docs.expo.io/versions/latest/introduction/faq.html#can-i-use-nodejs-packages-with-expo
[22:38:48] Failed building JavaScript bundle.
Then finally, the error that dooms me:
metro bundler has encountered an internal error, please check your terminal error output for more details.
I am trying to import famous into my application
When i create a breakpoint in the base index.html file in ember cli and look at what require seems to know about i see famo.us is there
in my brocfile i have tried the following
app.import('vendor/famous/famous.js', {
'famous/core/Context':''
});
app.import('vendor/famous/famous.js', {
'famous/core/Context':'default'
});
app.import('vendor/famous/famous.js');
this may be fixed by master of loader.js https://github.com/stefanpenner/loader.js/issues/25