Validate webpack configuration before running compiler

packages/neutrino/bin/build.js

@@ -8,7 +8,7 @@ module.exports = (middleware, options) => {
     .fork((errors) => {
       spinner.fail('Building project failed');
       errors.forEach((err) => {
-        console.error(err.stack || err);
+        console.error(err.message || err.stack || err);
         err.details && console.error(err.details);
       });
       process.exit(1);

packages/neutrino/bin/inspect.js

@@ -2,6 +2,6 @@ const { inspect } = require('../src');
 
 module.exports = (middleware, options) => inspect(middleware, options)
   .fork((err) => {
-    console.error(err.stack || err);
+    console.error(err.message || err.stack || err);
     process.exit(1);
   }, console.log);

packages/neutrino/bin/start.js

@@ -8,7 +8,7 @@ module.exports = (middleware, options) => {
     .fork((errors) => {
       spinner.fail('Building project failed');
       errors.forEach((err) => {
-        console.error(err.stack || err);
+        console.error(err.message || err.stack || err);
         err.details && console.error(err.details);
       });
 

packages/neutrino/bin/test.js

@@ -2,6 +2,6 @@ const { test } = require('../src');
 
 module.exports = (middleware, options) => test(middleware, options)
   .fork((err) => {
-    console.error(err.stack || err);
+    console.error(err.message || err.stack || err);
     process.exit(1);
   }, Function.prototype);

packages/neutrino/src/build.js

@@ -1,16 +1,10 @@
-const webpack = require('webpack');
 const Future = require('fluture');
-const { webpackErrors } = require('./utils');
+const { webpackCompile, validateWebpackConfig } = require('./utils');
 
 // build :: Object config -> Future (Array Error) Function
-const build = config => Future((reject, resolve) => {
-  const compiler = webpack(config);
-
-  compiler.run((err, stats) => {
-    const errors = webpackErrors(err, stats);
-
-    errors.length ? reject(errors) : resolve(stats);
-  });
-});
+const build = config => Future
+  .of(config)
+  .chain(validateWebpackConfig)
+  .chain(webpackCompile);
 
 module.exports = build;

packages/neutrino/src/devServer.js

@@ -1,19 +1,19 @@
 const merge = require('deepmerge');
-const webpack = require('webpack');
 const DevServer = require('webpack-dev-server');
 const Future = require('fluture');
+const { createWebpackCompiler, validateWebpackConfig } = require('./utils');
 
-// devServer :: Object webpackConfig -> Future () Function
-const devServer = webpackConfig => new Future((reject, resolve) => {
-  const config = merge({
-    devServer: { host: 'localhost', port: 5000, noInfo: true }
-  }, webpackConfig);
-  const { host, port } = config.devServer;
+// devServer :: Object config -> Future () Function
+const devServer = config => Future
+  .of(merge({ devServer: { host: 'localhost', port: 5000, noInfo: true } }, config))
+  .chain(validateWebpackConfig)
+  .chain(createWebpackCompiler)
+  .chain(compiler => Future((reject, resolve) => {
+    const { devServer } = compiler.options;
+    const { host, port } = devServer;
+    const server = new DevServer(compiler, devServer);
 
-  const compiler = webpack(config);
-  const server = new DevServer(compiler, config.devServer);
-
-  server.listen(port, host, () => resolve(compiler));
-});
+    server.listen(port, host, () => resolve(compiler));
+  }));
 
 module.exports = devServer;

packages/neutrino/src/utils.js

@@ -3,6 +3,7 @@ const { cond, curry, defaultTo, identity, map, memoize, of, partialRight, pipe,
 const { List } = require('immutable-ext');
 const { isAbsolute, join } = require('path');
 const optional = require('optional');
+const webpack = require('webpack');
 
 // any :: List -> Future a b
 const any = reduce(Future.or, Future.reject('empty list'));
@@ -50,9 +51,42 @@ const toArray = cond([
 // webpackErrors :: (Error|Array Error err -> Object stats) -> Array Error
 const webpackErrors = (err, stats) => (err ? toArray(err) : stats.toJson().errors);
 
+// createWebpackCompiler :: Object config -> Future Error Object
+const createWebpackCompiler = config => Future.of(config).map(webpack);
+
+// createWebpackValidator :: Object config -> Future Error Object
+const createWebpackValidator = config => Future.of(config).map(webpack.validate);
+
+// createWebpackWatcher :: Object config -> Future Error Object
+const createWebpackWatcher = config => createWebpackCompiler(config)
+  .chain(compiler => Future((reject, resolve) => {
+    compiler.watch(compiler.options.watchOptions || {}, (err, stats) => {
+      const errors = webpackErrors(err, stats);
+
+      errors.length ? reject(errors) : resolve(compiler);
+    });
+  }));
+
+// validateWebpackConfig :: Object config -> Future Error Object
+const validateWebpackConfig = config => createWebpackValidator(config)
+  .chain(errors => (errors.length ?
+    Future.reject([new webpack.WebpackOptionsValidationError(errors)]) :
+    Future.of(config)));
+
+// webpackCompile :: Object config -> Future Error Object
+const webpackCompile = config => createWebpackCompiler(config)
+  .chain(compiler => Future((reject, resolve) => compiler.run((err, stats) => {
+    const errors = webpackErrors(err, stats);
+
+    errors.length ? reject(errors) : resolve(stats);
+  })));
+
 module.exports = {
   any,
   createPaths,
+  createWebpackCompiler,
+  createWebpackValidator,
+  createWebpackWatcher,
   getNodeEnv,
   getPackageJson,
   normalizePath,
@@ -60,5 +94,7 @@ module.exports = {
   resolveAny,
   resolveSafe,
   toArray,
+  validateWebpackConfig,
+  webpackCompile,
   webpackErrors
 };

packages/neutrino/src/watch.js

@@ -1,16 +1,10 @@
-const webpack = require('webpack');
 const Future = require('fluture');
-const { webpackErrors } = require('./utils');
+const { createWebpackWatcher, validateWebpackConfig } = require('./utils');
 
 // watch :: Object config -> Future (Array Error) ()
-const watch = config => new Future((reject, resolve) => {
-  const compiler = webpack(config);
-
-  compiler.watch(config.watchOptions || {}, (err, stats) => {
-    const errors = webpackErrors(err, stats);
-
-    errors.length ? reject(errors) : resolve(compiler);
-  });
-});
+const watch = config => Future
+  .of(config)
+  .chain(validateWebpackConfig)
+  .chain(createWebpackWatcher);
 
 module.exports = watch;