Webpack normalModuleReplacmentPlugin not working correctly on Windows - windows

Question

I started to write library to fetch some data from an api in typescript and use webpack as a bundler.
We have a dev, test and prod api, so the lib should use differnt urls for each environment.
Webpack has the normalModuleReplacmentPlugin build in, to replace files, depending on the configuration. I created different environment files, which should be replaced by webpack.
I'm using Ubuntu 18.04, but one of our developer which is now working on the lib currently using windows. He noticed that the replacement is not working on his local machine.
webpack.config.js (example from my github repo)
const merge = require( 'webpack-merge' );
const path = require( 'path' );
const commonConfigObj = {
entry: {
'fooBar': './src/index.ts'
},
output: {
filename: '[name].js',
path: path.resolve( __dirname, 'dist' ),
library: 'FooBar',
libraryTarget: 'umd'
},
module: {
rules: [
{
test: /\.tsx?$/,
use: [
{
loader: 'ts-loader',
options: { configFile: 'tsconfig.json' }
}
]
}
]
},
resolve: {
extensions: [ '.ts', '.tsx', '.js' ]
},
profile: true
};
const commonConfig = merge( [ commonConfigObj ] );
const environments = {
'prod': require( './webpack/prod.config.js' ),
'dev': require( './webpack/dev.config.js' )
};
module.exports = mode=>{
if( mode ) {
const envConfig = environments[ mode.env ];
if( envConfig ) {
return merge( commonConfig, envConfig );
}
}
return merge( commonConfig, environments.dev );
};
webpack/prod.config.js (example from my github repo)
const CleanWebpackPlugin = require( 'clean-webpack-plugin' );
const BundleAnalyzerPlugin = require( 'webpack-bundle-analyzer' ).BundleAnalyzerPlugin;
const webpack = require('webpack');
module.exports = {
mode: 'production',
plugins: [
new CleanWebpackPlugin(),
new BundleAnalyzerPlugin( {
analyzerMode: 'disabled',
generateStatsFile: true
} ),
new webpack.NormalModuleReplacementPlugin(
/src\/environments\/environment.ts/,
'./environment.prod.ts'
),
],
devtool: 'source-map'
};
I'm sure that this is not a webpack issue but wrong usage.
GitHub repo: https://github.com/ManticSic/normalModuleReplacmentPlugin-issue-windows
Run npm ci and npm run build (or npm run build-dev for dev env).
You can find the important part at the end of line #1
expected: ...,t.environment={bar:"Prod"}...
result on windows: ...,t.environment={bar:"Normal"}...

Answer 1

Like expected the problem was sitting in front of the computer...
Wrong file system separators were used.
Replacing \/ with [\\\/] works fine!
Full regex: /src[\\\/]environments[\\\/]environment.ts/