compilation gets repeated several times on each rebuild

[iwinux]

env

• OS: macOS 10.12.3
• PureScript: 0.11.6
• Webpack: 3.4.1
• purs-loader: 3.0.0
• purescript-psa: 0.5.1
• pulp: 11.0.0

loader config

{
  test: /\.purs$/,
  loader: 'purs-loader',
  options: { bundle: true },
}

problem

Each time I run webpack --config webpack.config --watch, the compilation gets repeated several times (at least 5) before it shows webpack: Compiled successfully.. And when I modify source code to trigger rebuild, the compilation gets repeated again (less times than first startup, though).

[ethul]

Thanks for the report. I haven't tried the purs-loader on webpack 3.x or too much on 2.x. Perhaps there is some kind of incompatibility. I will have to investigate this further. Are you able to provide your webpack config?

[ethul]

I've updated the dependencies of the example and didn't notice recompilation occurring with or without bundling. Are you able to reproduce this issue using the purescript-webpack-example?

Thanks!

Note that I did see the invalid plugin hook being called multiple times in watch mode; however I am not sure if this is causing any issue.

[shamansir]

I have the same issue with the config like (I left some comments there so it's easy to see which options I tried to resolve the problems):

'use strict';

const path = require('path');
const webpack = require('webpack');

const isWebpackDevServer = process.argv.filter(a => path.basename(a) === 'webpack-dev-server').length;

const isWatch = process.argv.filter(a => a === '--watch').length

const plugins =
  isWebpackDevServer || !isWatch ? [] : [
    function(){
      this.plugin('done', function(stats){
        process.stderr.write(stats.toString('errors-only'));
      });
    }
  ]
;

module.exports = {
  // devtool: 'eval-source-map',

  devServer: {
    contentBase: '.',
    port: 4008/*,
    stats: 'errors-only'*/
  },

  entry: './src/Main.purs',

  output: {
    path: path.resolve(__dirname, 'output'),
    publicPath: '/output/',
    pathinfo: true,
    filename: 'app.js'
  },

  module: {
    rules: [
      {
        test: /\.purs$/,
        use: [
          {
            loader: 'purs-loader',
            options: {
              exclude: /output/,
              src: [
                'bower_components/purescript-*/src/**/*.purs',
                'src/**/*.purs'
              ],
              bundle: true,
              pscBundleArgs: {
                main: "Main"
              },
              psc: 'psa',
              watch: isWebpackDevServer || isWatch,
              pscIde: false
            }
          }
        ]
      },
    ]
  },

  resolve: {
    modules: [ 'node_modules', 'bower_components' ],
    //root: [ path.resolve('./src') ],
    extensions: [ '.purs', '.js']
  },

  // devServer : {
  //   contentBase : './output'
  // },

  plugins: [
    new webpack.LoaderOptionsPlugin({
      debug: true
    })
  ].concat(plugins)
};

I think the issue could be connected with a single entry module which is what I am trying to make work now — so without bundle: true there is no sense in passing pscBundleArgs (see #33). And when I do, it goes into infinite rebuild.

My bundle is located in output/app.js file. Without a bundle flag, It gets re-compiled well, as I see in the sources, but lacks the call of Main module, so the page is empty.

On the contrary, pulp server is working fine with this configuration :).

[ethul]

Thanks for the report and config example. Out of curiosity, what version of PureScript, purs-loader, webpack, node, etc., are you using?