Develop Reference

How do I start my React App After I clone it?

I'm currently trying to deploy my app with netlify, but the problem is that I clone my app into my new computer, and now I'm getting some issues.
> todolistv2#1.0.0 start /Users/hvaandres/Documents/GitHub/TodoList_React
> npm run build
npm ERR! missing script: build
npm ERR! A complete log of this run can be found in:
npm ERR! /Users/hvaandres/.npm/_logs/2021-03-04T06_19_54_506Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! todolistv2#1.0.0 start: `npm run build`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the todolistv2#1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /Users/hvaandres/.npm/_logs/2021-03-04T06_19_54_546Z-debug.log
I ran the following command npm install and I'm still getting the same issue. This is my debug log:
0 info it worked if it ends with ok
1 verbose cli [ '/usr/local/bin/node', '/usr/local/bin/npm', 'run', 'deploy' ]
2 info using npm#6.14.11
3 info using node#v14.15.5
4 verbose run-script [ 'predeploy', 'deploy', 'postdeploy' ]
5 info lifecycle todolistv2#1.0.0~predeploy: todolistv2#1.0.0
6 info lifecycle todolistv2#1.0.0~deploy: todolistv2#1.0.0
7 verbose lifecycle todolistv2#1.0.0~deploy: unsafe-perm in lifecycle true
8 verbose lifecycle todolistv2#1.0.0~deploy: PATH: /usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/Users/hvaandres/Documents/GitHub/TodoList_React/node_modules/.bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Apple/usr/bin
9 verbose lifecycle todolistv2#1.0.0~deploy: CWD: /Users/hvaandres/Documents/GitHub/TodoList_React
10 silly lifecycle todolistv2#1.0.0~deploy: Args: [ '-c', 'npm run build && gh-pages -d build' ]
11 silly lifecycle todolistv2#1.0.0~deploy: Returned: code: 1 signal: null
12 info lifecycle todolistv2#1.0.0~deploy: Failed to exec deploy script
13 verbose stack Error: todolistv2#1.0.0 deploy: `npm run build && gh-pages -d build`
13 verbose stack Exit status 1
13 verbose stack at EventEmitter.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/index.js:332:16)
13 verbose stack at EventEmitter.emit (events.js:315:20)
13 verbose stack at ChildProcess.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:55:14)
13 verbose stack at ChildProcess.emit (events.js:315:20)
13 verbose stack at maybeClose (internal/child_process.js:1048:16)
13 verbose stack at Process.ChildProcess._handle.onexit (internal/child_process.js:288:5)
14 verbose pkgid todolistv2#1.0.0
15 verbose cwd /Users/hvaandres/Documents/GitHub/TodoList_React
16 verbose Darwin 19.6.0
17 verbose argv "/usr/local/bin/node" "/usr/local/bin/npm" "run" "deploy"
18 verbose node v14.15.5
19 verbose npm v6.14.11
20 error code ELIFECYCLE
21 error errno 1
22 error todolistv2#1.0.0 deploy: `npm run build && gh-pages -d build`
22 error Exit status 1
23 error Failed at the todolistv2#1.0.0 deploy script.
23 error This is probably not a problem with npm. There is likely additional logging output above.
24 verbose exit [ 1, true ]
My package.json:
{
"name": "todolistv2",
"version": "1.0.0",
"description": "Todo-List",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "npm run build"
},
"keywords": [
"react",
"todolist_project"
],
"author": "Alan A. Haro",
"license": "ISC",
"dependencies": {
"react-icons": "^3.11.0"
}
}
If someone can help me, I would really appreciate it. I'm just trying to learn more.

Step 1
you need a Node and Npm in your System
Click here for installing Node.js and npm
Step 2
delete Package-lock.json file
Step 3
For installing Node Modules :
Run Command npm install
Step 4
Run Command npm start
if not working then try Command
npm run build
or
npm run dev
if Still not working then open package.json file
and check
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "npm run build" // your script code is "npm run build"
},

Your package JSON file appears to be missing both a start and build command. Add them back in. These are the defaults for newly created React apps using create-react-app. You also appear to be missing dependencies, namely react and react-dom.
{
"name": "todolistv2",
"version": "1.0.0",
"description": "Todo-List",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "react-scripts start",
"build": "react-scripts build"
},
"keywords": [
"react",
"todolist_project"
],
"author": "Alan A. Haro",
"license": "ISC",
"dependencies": {
"react": "^16.13.1",
"react-dom": "^16.13.1",
"react-icons": "^3.11.0",
... add any other missing dependencies!!
}
}

Failed npm start because of missing module 'minizlib'

I cloned a react-native project from github to work on, but npm start fails and reads this:
Error: Cannot find module 'minizlib'
Require stack:
- /usr/local/lib/node_modules/expo-cli/node_modules/tar/lib/pack.js
- /usr/local/lib/node_modules/expo-cli/node_modules/tar/lib/create.js
- /usr/local/lib/node_modules/expo-cli/node_modules/tar/index.js
- /usr/local/lib/node_modules/expo-cli/node_modules/#expo/xdl/build/Extract.js
- /usr/local/lib/node_modules/expo-cli/node_modules/#expo/xdl/build/Api.js
- /usr/local/lib/node_modules/expo-cli/node_modules/#expo/xdl/build/xdl.js
- /usr/local/lib/node_modules/expo-cli/build/exp.js
- /usr/local/lib/node_modules/expo-cli/bin/expo.js
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:625:15)
at Function.Module._load (internal/modules/cjs/loader.js:527:27)
at Module.require (internal/modules/cjs/loader.js:683:19)
at require (internal/modules/cjs/helpers.js:16:16)
at Object.<anonymous> (/usr/local/lib/node_modules/expo-cli/node_modules/tar/lib/pack.js:28:14)
at Module._compile (internal/modules/cjs/loader.js:776:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)
at Module.load (internal/modules/cjs/loader.js:643:32)
at Function.Module._load (internal/modules/cjs/loader.js:556:12)
at Module.require (internal/modules/cjs/loader.js:683:19)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! # start: `expo start`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the # start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! /home/yeastbeast/.npm/_logs/2019-07-07T13_59_02_331Z-debug.log
Here is the debug log file:
1 verbose cli [ '/usr/bin/node', '/usr/bin/npm', 'start' ]
2 info using npm#6.9.0
3 info using node#v12.6.0
4 verbose run-script [ 'prestart', 'start', 'poststart' ]
5 info lifecycle #~prestart: #
6 info lifecycle #~start: #
7 verbose lifecycle #~start: unsafe-perm in lifecycle true
8 verbose lifecycle #~start: PATH: /usr/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/home/geoffrey/mhs-protect/node_modules/.bin:/home/geoffrey/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
9 verbose lifecycle #~start: CWD: /home/geoffrey/mhs-protect
10 silly lifecycle #~start: Args: [ '-c', 'expo start' ]
11 silly lifecycle #~start: Returned: code: 1 signal: null
12 info lifecycle #~start: Failed to exec start script
13 verbose stack Error: # start: `expo start`
13 verbose stack Exit status 1
13 verbose stack at EventEmitter.<anonymous> (/usr/lib/node_modules/npm/node_modules/npm-lifecycle/index.js:301:16)
13 verbose stack at EventEmitter.emit (events.js:203:13)
13 verbose stack at ChildProcess.<anonymous> (/usr/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:55:14)
13 verbose stack at ChildProcess.emit (events.js:203:13)
13 verbose stack at maybeClose (internal/child_process.js:1021:16)
13 verbose stack at Process.ChildProcess._handle.onexit (internal/child_process.js:283:5)
14 verbose pkgid #
15 verbose cwd /home/geoffrey/mhs-protect
16 verbose Linux 4.18.0-25-generic
17 verbose argv "/usr/bin/node" "/usr/bin/npm" "start"
18 verbose node v12.6.0
19 verbose npm v6.9.0
20 error code ELIFECYCLE
21 error errno 1
22 error # start: `expo start`
22 error Exit status 1
23 error Failed at the # start script.
23 error This is probably not a problem with npm. There is likely additional logging output above.
24 verbose exit [ 1, true ]
I have tried installing and reinstalling minizlib, npm, and node, and also a handful of possible solutions found in similar questions here, but have had no success. Any help would be appreciated.
Os: Ubuntu 18.04.2
link to github repo
Edit:
I'm not quite sure what happened but it does seem to working. I opened the project today to see if anything changed and received some warnings about vulnerabilities. To fix them i reinstalled expo-cli and now all seems to be working correctly.

Your package.json files contains this,
{
"main": "node_modules/expo/AppEntry.js",
"scripts": {
"start": "expo start",
"android": "expo start --android",
"ios": "expo start --ios",
"eject": "expo eject"
},
"dependencies": {
"braces": "^2.3.1",
"expo": "^32.0.0",
"firebase": "^6.1.0",
"react": "16.5.0",
"react-native": "https://github.com/expo/react-native/archive/sdk-32.0.0.tar.gz",
"react-navigation": "^3.11.0",
"ws": "^3.3.3"
},
"devDependencies": {
"babel-preset-expo": "^5.0.0"
},
"private": true
}
package.json file don't have entry for minizlib package. Also node_modules folder don't have minizlib folder.
Probably missing to install the same, you can do this,
npm install minizlib --save //here `--save` will create entry into `package.json` file
After installing this package you need to restart your app.

npm install -g npm#latest (to update npm).
rm -rf node_modules (to remove the existing modules).
npm install (to re-install the project dependencies).

npm run deploy script not giving link

I keep getting this error message when I try to use npm run deploy.
However, I do seem to have a deploy script in my package.json file
I am also cded into the package.json directory
I have tried turning github pages on but when I go to the link it gives me a 404 error
As a result I have turned off github pages
Extended Error message (npm debug log):
14 verbose lifecycle myportfoliosite#0.1.0~deploy: CWD: C:\Users\Ali Haider\AppData\Roaming\npm\node_modules\create-react-app\myportfoliosite\myportfoliosite
15 silly lifecycle myportfoliosite#0.1.0~deploy: Args: [ '/d /s /c', 'gh-pages -d build' ]
16 silly lifecycle myportfoliosite#0.1.0~deploy: Returned: code: 1 signal: null
17 info lifecycle myportfoliosite#0.1.0~deploy: Failed to exec deploy script
18 verbose stack Error: myportfoliosite#0.1.0 deploy: `gh-pages -d build`
18 verbose stack Exit status 1
18 verbose stack at EventEmitter.<anonymous> (C:\Program Files\nodejs\node_modules\npm\node_modules\npm-lifecycle\index.js:301:16)
18 verbose stack at EventEmitter.emit (events.js:198:13)
18 verbose stack at ChildProcess.<anonymous> (C:\Program Files\nodejs\node_modules\npm\node_modules\npm-lifecycle\lib\spawn.js:55:14)
18 verbose stack at ChildProcess.emit (events.js:198:13)
18 verbose stack at maybeClose (internal/child_process.js:982:16)
18 verbose stack at Process.ChildProcess._handle.onexit (internal/child_process.js:259:5)
19 verbose pkgid myportfoliosite#0.1.0
20 verbose cwd C:\Users\Ali Haider\AppData\Roaming\npm\node_modules\create-react-app\myportfoliosite\myportfoliosite
21 verbose Windows_NT 10.0.17134
22 verbose argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "run" "deploy"
23 verbose node v10.16.0
24 verbose npm v6.9.0
25 error code ELIFECYCLE
26 error errno 1
27 error myportfoliosite#0.1.0 deploy: `gh-pages -d build`
27 error Exit status 1
28 error Failed at the myportfoliosite#0.1.0 deploy script.
28 error This is probably not a problem with npm. There is likely additional logging output above.
29 verbose exit [ 1, true ]
File sizes after gzip:
73.02 KB build\static\js\2.f6e5e996.chunk.js
19.04 KB build\static\css\2.b1979bb4.chunk.css
797 B build\static\js\runtime~main.4f085a03.js
152 B build\static\js\main.a0a932a3.chunk.js
The project was built assuming it is hosted at /InquisitiveDev2016/ReactDeveloperPortfolio/.
You can control this with the homepage field in your package.json.
The build folder is ready to be deployed.
Find out more about deployment here:
Error appearing in terminal:
> myportfoliosite#0.1.0 deploy C:\Users\Ali Haider\AppData\Roaming\npm\node_modules\create-react-app\myportfoliosite\myportfoliosite
> gh-pages -d build
'gh-pages' is not recognized as an internal or external command,
operable program or batch file.
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! myportfoliosite#0.1.0 deploy: `gh-pages -d build`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the myportfoliosite#0.1.0 deploy script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\Ali Haider\AppData\Roaming\npm-cache\_logs\2019-06-29T02_08_30_836Z-debug.log
Here is my repository: https://github.com/InquisitiveDev2016/ReactDeveloperPortfolio
My json folder:
{
"name": "myportfoliosite",
"version": "0.1.0",
"private": true,
"homepage": "https://github.com/InquisitiveDev2016/ReactDeveloperPortfolio",
"dependencies": {
"react": "^16.8.6",
"react-dom": "^16.8.6",
"react-mdl": "^1.11.0",
"react-router-dom": "^5.0.1",
"react-scripts": "3.0.1"
},
"scripts": {
"start": "react-scripts start",
"build": "react-scripts build",
"test": "react-scripts test",
"predeploy": "npm run build",
"deploy": "gh-pages -d build",
"eject": "react-scripts eject"
},
"eslintConfig": {
"extends": "react-app"
},
"browserslist": {
"production": [
">0.2%",
"not dead",
"not op_mini all"
],
"development": [
"last 1 chrome version",
"last 1 firefox version",
"last 1 safari version"
]
}
}

check your folder tree there you might find build folder there delete catch folder and save then run npm run deploy

Error while compiling the project with npm

I am trying to get a project running and when I execute the npm install it installs all the dependencies.
But after that I try to execute npm run compile and it gives me an error.
Here is the log file for better understanding the error.
0 info it worked if it ends with ok
1 verbose cli [ '/Users/roxhens/.nvm/versions/node/v10.13.0/bin/node',
1 verbose cli '/Users/roxhens/.nvm/versions/node/v10.13.0/bin/npm',
1 verbose cli 'run',
1 verbose cli 'build' ]
2 info using npm#6.4.1
3 info using node#v10.13.0
4 verbose run-script [ 'prebuild', 'build', 'postbuild' ]
5 info lifecycle jsonforms-tooling-common#0.0.1~prebuild: jsonforms-tooling-common#0.0.1
6 info lifecycle jsonforms-tooling-common#0.0.1~build: jsonforms-tooling-common#0.0.1
7 verbose lifecycle jsonforms-tooling-common#0.0.1~build: unsafe-perm in lifecycle true
8 verbose lifecycle jsonforms-tooling-common#0.0.1~build: PATH: /Users/roxhens/.nvm/versions/node/v10.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/Users/roxhens/Desktop/GitHub/jsonforms-tooling/jsonforms-tooling-common/node_modules/.bin:/Users/roxhens/Desktop/GitHub/jsonforms-tooling/jsonforms-tooling-common/node_modules/.bin:/Users/roxhens/Desktop/GitHub/jsonforms-tooling/node_modules/.bin:/Users/roxhens/Desktop/GitHub/node_modules/.bin:/Users/roxhens/Desktop/node_modules/.bin:/Users/roxhens/node_modules/.bin:/Users/node_modules/.bin:/node_modules/.bin:/Users/roxhens/.nvm/versions/node/v10.13.0/bin:/Users/roxhens/.nvm/versions/node/v10.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/Users/roxhens/Desktop/GitHub/jsonforms-tooling/node_modules/.bin:/Users/roxhens/.nvm/versions/node/v10.13.0/bin:/Library/Frameworks/Python.framework/Versions/3.6/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Frameworks/Python.framework/Versions/3.6/bin
9 verbose lifecycle jsonforms-tooling-common#0.0.1~build: CWD: /Users/roxhens/Desktop/GitHub/jsonforms-tooling/jsonforms-tooling-common
10 silly lifecycle jsonforms-tooling-common#0.0.1~build: Args: [ '-c', 'npm run compile' ]
11 silly lifecycle jsonforms-tooling-common#0.0.1~build: Returned: code: 2 signal: null
12 info lifecycle jsonforms-tooling-common#0.0.1~build: Failed to exec build script
13 verbose stack Error: jsonforms-tooling-common#0.0.1 build: `npm run compile`
13 verbose stack Exit status 2
13 verbose stack at EventEmitter.<anonymous> (/Users/roxhens/.nvm/versions/node/v10.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/index.js:301:16)
13 verbose stack at EventEmitter.emit (events.js:182:13)
13 verbose stack at ChildProcess.<anonymous> (/Users/roxhens/.nvm/versions/node/v10.13.0/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:55:14)
13 verbose stack at ChildProcess.emit (events.js:182:13)
13 verbose stack at maybeClose (internal/child_process.js:962:16)
13 verbose stack at Process.ChildProcess._handle.onexit (internal/child_process.js:251:5)
14 verbose pkgid jsonforms-tooling-common#0.0.1
15 verbose cwd /Users/roxhens/Desktop/GitHub/jsonforms-tooling/jsonforms-tooling-common
16 verbose Darwin 18.2.0
17 verbose argv "/Users/roxhens/.nvm/versions/node/v10.13.0/bin/node" "/Users/roxhens/.nvm/versions/node/v10.13.0/bin/npm" "run" "build"
18 verbose node v10.13.0
19 verbose npm v6.4.1
20 error code ELIFECYCLE
21 error errno 2
22 error jsonforms-tooling-common#0.0.1 build: `npm run compile`
22 error Exit status 2
23 error Failed at the jsonforms-tooling-common#0.0.1 build script.
23 error This is probably not a problem with npm. There is likely additional logging output above.
24 verbose exit [ 2, true ]
This is the package.json in the project root directory.
{
"scripts": {
"lerna": "lerna",
"coveralls": "ts-jest --coverage && cat ./tests/coverage/lcov.info | coveralls",
"postinstall": "npm run lernabootstrap && npm run lernainstall",
"lernainstall": "lerna exec --no-bail --npm-ci-mode -- npm run custominstall",
"lernabootstrap": "lerna bootstrap --npm-ci-mode --ignore-scripts",
"compile": "lerna run build",
"lint": "lerna run lint"
},
"devDependencies": {
"#types/jest": "^23.3.11",
"#types/node": "^10.12.10",
"coveralls": "^3.0.2",
"jest": "^23.6.0",
"lerna": "^3.4.3",
"rimraf": "2.6.3",
"ts-jest": "^23.10.4",
"tslint": "^5.11.0",
"tslint-react": "^3.6.0",
"typescript": "^3.1.6",
"vscode": "^1.1.21"
},
"dependencies": {
"#jsonforms/core": "^2.0.12",
"simple-git": "^1.107.0"
}
}

I guess that you're trying to build the following:
https://github.com/eclipsesource/jsonforms-tooling
When trying to build libraries found on GitHub (or elsewhere), you can look at how they build it on their CI or look at some other scripts. It seems that for this particular lib, their .travis.yml does not contain everything to make it work on all platforms.
I fiddled with it for a bit and running these (rather straightforward) commands from the root folder should solve your problem:
git clone https://github.com/eclipsesource/jsonforms-tooling
cd jsonforms-tooling
npm install
npm run compile

I still cannot find the reason why that error, but I managed to fix it by deleting the files and cloning the repository again.

Webpack build fails only when webpack.config.js exists

I've searched this to death and haven't found a solution. I'm using webpack for the first time not set up for me via Laravel of Vue.js automated tools. Webpack builds just fine in production or development modes without the webpack.config.js config file present (zero-config mode), but throws a very unhelpful error when I add in the webpack.config.js file to set up the Babel loader. I'm on Windows, if that affects anything.
My package.json:
{
"name": "portfolio_update",
"version": "1.0.0",
"description": "Port to Vue.js",
"main": "src/index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"build": "webpack --mode production",
"dev": "webpack --mode development",
"watch": "webpack --watch --mode production"
},
"author": "Jake Runge",
"license": "ISC",
"devDependencies": {
"babel-core": "^6.26.3",
"babel-loader": "^7.1.4",
"babel-preset-env": "^1.7.0",
"webpack": "^4.12.0",
"webpack-cli": "^3.0.8"
},
"dependencies": {
"jquery": "^3.3.1"
}
}
webpack.config.js:
module.exports = {
module: {
rules: [{
test: /\.js$/,
exclude: /node_modules/,
loader: 'babel-loader'
}]
}
}
unhelpful debug log:
0 info it worked if it ends with ok
1 verbose cli [ 'C:\\Program Files\\nodejs\\node.exe',
1 verbose cli 'C:\\Users\\jwrun\\AppData\\Roaming\\npm\\node_modules\\npm\\bin\\npm-cli.js',
1 verbose cli 'run',
1 verbose cli 'dev' ]
2 info using npm#5.8.0
3 info using node#v8.9.3
4 verbose run-script [ 'predev', 'dev', 'postdev' ]
5 info lifecycle portfolio_update#1.0.0~predev: portfolio_update#1.0.0
6 info lifecycle portfolio_update#1.0.0~dev: portfolio_update#1.0.0
7 verbose lifecycle portfolio_update#1.0.0~dev: unsafe-perm in lifecycle true
8 verbose lifecycle portfolio_update#1.0.0~dev: PATH: C:\Users\jwrun\AppData\Roaming\npm\node_modules\npm\node_modules\npm-lifecycle\node-gyp-bin;C:\Bitnami\wampstack-7.1.12-0\apache2\htdocs\Portfolio_update\node_modules\.bin;C:\Program Files (x86)\Intel\iCLS Client\;C:\Program Files (x86)\Common Files\Intel\Shared Libraries\redist\intel64\compiler;C:\Program Files\Intel\iCLS Client\;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\nodejs\;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files\PuTTY\;C:\Bitnami\wampstack-7.1.12-0\php;C:\ProgramData\ComposerSetup\bin;C:\HashiCorp\Vagrant\bin;C:\Program Files\Git\cmd;C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\DAL;C:\Program Files\Intel\Intel(R) Management Engine Components\DAL;C:\Program Files (x86)\Intel\Intel(R) Management Engine Components\IPT;C:\Program Files\Intel\Intel(R) Management Engine Components\IPT;C:\WINDOWS\System32\OpenSSH\;C:\Users\jwrun\AppData\Local\Programs\Python\Python36-32\Scripts\;C:\Users\jwrun\AppData\Local\Programs\Python\Python36-32\;C:\Users\jwrun\AppData\Local\Microsoft\WindowsApps;C:\Users\jwrun\AppData\Local\GitHubDesktop\bin;C:\Users\jwrun\AppData\Roaming\npm;C:\Users\jwrun\AppData\Local\Microsoft\WindowsApps;C:\Users\jwrun\AppData\Roaming\Composer\vendor\bin;C:\Program Files\Microsoft VS Code\bin;C:\Program Files\MongoDB\Server\3.6\bin
9 verbose lifecycle portfolio_update#1.0.0~dev: CWD: C:\Bitnami\wampstack-7.1.12-0\apache2\htdocs\Portfolio_update
10 silly lifecycle portfolio_update#1.0.0~dev: Args: [ '/d /s /c', 'webpack --mode development' ]
11 silly lifecycle portfolio_update#1.0.0~dev: Returned: code: 1 signal: null
12 info lifecycle portfolio_update#1.0.0~dev: Failed to exec dev script
13 verbose stack Error: portfolio_update#1.0.0 dev: `webpack --mode development`
13 verbose stack Exit status 1
13 verbose stack at EventEmitter.<anonymous> (C:\Users\jwrun\AppData\Roaming\npm\node_modules\npm\node_modules\npm-lifecycle\index.js:283:16)
13 verbose stack at emitTwo (events.js:126:13)
13 verbose stack at EventEmitter.emit (events.js:214:7)
13 verbose stack at ChildProcess.<anonymous> (C:\Users\jwrun\AppData\Roaming\npm\node_modules\npm\node_modules\npm-lifecycle\lib\spawn.js:55:14)
13 verbose stack at emitTwo (events.js:126:13)
13 verbose stack at ChildProcess.emit (events.js:214:7)
13 verbose stack at maybeClose (internal/child_process.js:925:16)
13 verbose stack at Process.ChildProcess._handle.onexit (internal/child_process.js:209:5)
14 verbose pkgid portfolio_update#1.0.0
15 verbose cwd C:\Bitnami\wampstack-7.1.12-0\apache2\htdocs\Portfolio_update
16 verbose Windows_NT 10.0.17134
17 verbose argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Users\\jwrun\\AppData\\Roaming\\npm\\node_modules\\npm\\bin\\npm-cli.js" "run" "dev"
18 verbose node v8.9.3
19 verbose npm v5.8.0
20 error code ELIFECYCLE
21 error errno 1
22 error portfolio_update#1.0.0 dev: `webpack --mode development`
22 error Exit status 1
23 error Failed at the portfolio_update#1.0.0 dev script.
23 error This is probably not a problem with npm. There is likely additional logging output above.
24 verbose exit [ 1, true ]
Other setup is standard: There is the recommended src/ folder containing index.js entry point, and a dist/ folder to receive the bundled main.js file. It all works until I create the webpack.config.js file--even blank, with no configuration, I get an error. The file cannot exist or I get an error.
Thanks for any help and guidance anyone can give!

At last, I got it figured out! I wish the answer were complex and difficult to implement, given all the time I've put into this issue, but it was as simple as updating my Node and NPM versions.
I updated NPM from 5.8.0 to 6.1.0; I updated Node from 8.9.3 to the most recent, 10.4.1. Webpack does not need specified entry and output settings in the config file.
This was fairly unscientific, so I'm not sure if it was the Node upgrade or the NPM upgrade that helped, or if I could have updated to a less recent version of either--but if anyone else is having trouble, try a more recent Node or NPM version.