Create some sub compilations for tests

This result will not be used for serving the pages but will be used for tracking lint/type errors in those files

Author: rricard

packages/react-dev-utils/WatchTestFilesPlugin.js

@@ -1,5 +1,7 @@
 var glob = require('glob');
 var path = require('path');
+var os = require('os');
+var SingleEntryPlugin = require('webpack/lib/SingleEntryPlugin');
 
 function computeGlob(pattern, options) {
   return new Promise((resolve, reject) => {
@@ -26,26 +28,48 @@ function WatchTestFilesPlugin(testGlobs) {
   this.testGlobs = testGlobs || [];
 }
 
-WatchTestFilesPlugin.prototype.apply = function(compiler) {
-  var testFiles = [];
-  compiler.plugin('make', (compilation, callback) => {
-    getGlobs(this.testGlobs, compiler.options.context)
-    .then(foundFiles => {
-      testFiles = foundFiles;
-      return Promise.all(
-        testFiles.map(filename => new Promise((resolve, reject) => {
-          // TODO: add to modules
-          resolve(filename);
-        }))
-      )
-    })
-    .then(callback);
+function compileTestFile(compiler, compilation, context, testFile) {
+  var outputOptions = {
+    filename: path.join(os.tmpdir(), '__compiledTests__', testFile),
+    publicPath: compilation.outputOptions.publicPath,
+  };
+  var compilerName = "WatchTestFiles compilation for " + testFile;
+  var childCompiler = compilation.createChildCompiler(compilerName, outputOptions);
+  childCompiler.context = context;
+  childCompiler.apply(
+    new SingleEntryPlugin(context, path.join(compiler.options.context, testFile))
+  );
+  return new Promise((resolve, reject) => {
+    childCompiler.runAsChild((err, entries, childCompilation) => {
+      if (err) {
+        return reject(err);
+      }
+      resolve({
+        errors: childCompilation.errors,
+        warnings: childCompilation.warnings,
+      });
+    });
   });
+}
+
+WatchTestFilesPlugin.prototype.apply = function(compiler) {
   compiler.plugin('emit', (compilation, callback) => {
-    testFiles.forEach(testFile => {
-      compilation.fileDependencies.push(path.join(compiler.options.context, testFile));
-    });
-    callback();
+    getGlobs(this.testGlobs, compiler.options.context)
+    .then(foundFiles => Promise.all(
+      foundFiles.map(filename => {
+        // Add them to the list of watched files (for auto-reloading)
+        compilation.fileDependencies.push(path.join(compiler.options.context, filename));
+        // Create and run a sub-compiler for the file to send it through the loaders
+        return compileTestFile(compiler, compilation, compiler.context, filename)
+      })
+    ))
+    .then((results) => {
+      var errors = results.reduce((list, res) => list.concat(res.errors || []), []);
+      var warnings = results.reduce((list, res) => list.concat(res.warnings || []), []);
+      compilation.errors = compilation.errors.concat(errors);
+      compilation.warnings = compilation.warnings.concat(warnings);
+      callback();
+    }, callback);
   });
 };
 

packages/react-dev-utils/package.json

@@ -32,5 +32,11 @@
     "opn": "4.0.2",
     "sockjs-client": "1.0.3",
     "strip-ansi": "3.0.1"
+  },
+  "devDependencies": {
+    "webpack": "1.14.0"
+  },
+  "peerDependencies": {
+    "webpack": "1.14.0"
   }
 }