Trying to run babel : "cannot find module #babel/core" - babeljs

Question

I'm trying to set up a build environment to explore react.
My build process uses gulp.
I installed packages like this:
npm install --save-dev gulp-babel#7 babel-core babel-preset-env
After discovering that I needed to install something related to babel and react I also ran:
npm install --save-dev #babel/preset-react
My .babelrc has this:
{ "presets": ["#babel/preset-react"] }
My gulpfile has this:
gulp.task('scripts', function() {
return gulp.src(['./src/js/main.js' ])
.pipe(babel({
presets : ['#babel/preset/react']
}))
.pipe(concat('test.js'))
.pipe(gulp.dest('./js'))
.pipe(uglify())
.pipe(rename('test.min.js'))
.pipe(gulp.dest('./js')) ;
});
When I run 'gulp scripts' I get this:
[22:51:14] Using gulpfile ~/play/learning-react-2/gulpfile.js
[22:51:14] Starting 'scripts'...
[22:51:14] 'scripts' errored after 59 ms
[22:51:14] Error in plugin "gulp-babel"
Message:
Cannot find module '#babel/core' (While processing preset: "/home/bob/play/learning-react-2/node_modules/#babel/preset-react/lib/index.js")
I deleted babel-core from node_modules, and reinstalled it using the command:
npm install --save-dev #babel/core
If I look at the contents of node_modules, I see these packages related to babel:
babel-code-frame/
babel-helper-builder-binary-assignment-operator-visitor/
babel-helper-call-delegate/
babel-helper-define-map/
babel-helper-explode-assignable-expression/
babel-helper-function-name/
babel-helper-get-function-arity/
babel-helper-hoist-variables/
babel-helper-optimise-call-expression/
babel-helper-regex/
babel-helper-remap-async-to-generator/
babel-helper-replace-supers/
babel-messages/
babel-plugin-check-es2015-constants/
babel-plugin-syntax-async-functions/
babel-plugin-syntax-exponentiation-operator/
babel-plugin-syntax-trailing-function-commas/
babel-plugin-transform-async-to-generator/
babel-plugin-transform-es2015-arrow-functions/
babel-plugin-transform-es2015-block-scoped-functions/
babel-plugin-transform-es2015-block-scoping/
babel-plugin-transform-es2015-classes/
babel-plugin-transform-es2015-computed-properties/
babel-plugin-transform-es2015-destructuring/
babel-plugin-transform-es2015-duplicate-keys/
babel-plugin-transform-es2015-for-of/
babel-plugin-transform-es2015-function-name/
babel-plugin-transform-es2015-literals/
babel-plugin-transform-es2015-modules-amd/
babel-plugin-transform-es2015-modules-commonjs/
babel-plugin-transform-es2015-modules-systemjs/
babel-plugin-transform-es2015-modules-umd/
babel-plugin-transform-es2015-object-super/
babel-plugin-transform-es2015-parameters/
babel-plugin-transform-es2015-shorthand-properties/
babel-plugin-transform-es2015-spread/
babel-plugin-transform-es2015-sticky-regex/
babel-plugin-transform-es2015-template-literals/
babel-plugin-transform-es2015-typeof-symbol/
babel-plugin-transform-es2015-unicode-regex/
babel-plugin-transform-exponentiation-operator/
babel-plugin-transform-regenerator/
babel-plugin-transform-strict-mode/
babel-preset-env/
babel-runtime/
babel-template/
babel-traverse/
babel-types/
I'm guessing that at least one of them is "babel core"
So... how do I actually run babel from gulp? How do I run it at all?

Answer 1

I had the same issue. I resolved it by removing node_modules and I reinstalled packages (with yarn OR npm install). The problem was fixed.

Answer 2

In case Victor's answer doesn't help, it may be worth a try to clean your machine's package cache by running npm cache clean/yarn cache clean or removing the cache folder manually.