fix: show warning for non-web targets

lib/Server.js

@@ -84,7 +84,7 @@ class Server {
 
     // eslint-disable-next-line no-shadow
     compilers.forEach((compiler) => {
-      new DevServerPlugin(this.options).apply(compiler);
+      new DevServerPlugin(this.options, this.logger).apply(compiler);
     });
   }
 

lib/utils/DevServerPlugin.js

@@ -10,9 +10,11 @@ const EntryPlugin = webpack.EntryPlugin;
 class DevServerPlugin {
   /**
    * @param {?Object} options - Dev-Server options
+   * @param {?Object} logger - Dev-Server logger
    */
-  constructor(options) {
+  constructor(options, logger) {
     this.options = options;
+    this.logger = logger;
   }
 
   /**
@@ -190,6 +192,13 @@ class DevServerPlugin {
       additionalEntries.push(hotEntry);
     }
 
+    if (!isWebTarget) {
+      this.logger.info(`A non-web target was selected in dev server config.`);
+      if (this.options.liveReload) {
+        this.logger.warn(`Live reload will not work with a non-web target.`);
+      }
+    }
+
     // use a hook to add entries if available
     if (EntryPlugin) {
       for (const additionalEntry of additionalEntries) {

test/e2e/DevServer.test.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { testBin } = require('../helpers/test-bin');
+const { testBin, normalizeStderr } = require('../helpers/test-bin');
 const isWebpack5 = require('../helpers/isWebpack5');
 
 describe('DevServer', () => {
@@ -124,4 +124,20 @@ describe('DevServer', () => {
         .catch(done);
     }
   );
+
+  it('should show a warning for live reloading with non-web target', (done) => {
+    testBin(
+      '--target node --live-reload',
+      './test/fixtures/dev-server/default-config.js'
+    )
+      .then((output) => {
+        expect(output.exitCode).toEqual(0);
+        expect(
+          normalizeStderr(output.stderr, { ipv6: true })
+        ).toMatchSnapshot();
+
+        done();
+      })
+      .catch(done);
+  });
 });

test/e2e/__snapshots__/DevServer.test.js.snap.webpack4

@@ -0,0 +1,11 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`DevServer should show a warning for live reloading with non-web target 1`] = `
+"<i> [webpack-dev-server] A non-web target was selected in dev server config.
+<w> [webpack-dev-server] Live reload will not work with a non-web target.
+<i> [webpack-dev-server] Project is running at:
+<i> [webpack-dev-server] Loopback: http://localhost:<port>/
+<i> [webpack-dev-server] On Your Network (IPv4): http://<network-ip-v4>:<port>/
+<i> [webpack-dev-server] On Your Network (IPv6): http://[<network-ip-v6>]:<port>/
+<i> [webpack-dev-server] Content not from webpack is served from '<cwd>/public' directory"
+`;

test/e2e/__snapshots__/DevServer.test.js.snap.webpack5

@@ -0,0 +1,11 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`DevServer should show a warning for live reloading with non-web target 1`] = `
+"<i> [webpack-dev-server] A non-web target was selected in dev server config.
+<w> [webpack-dev-server] Live reload will not work with a non-web target.
+<i> [webpack-dev-server] Project is running at:
+<i> [webpack-dev-server] Loopback: http://localhost:<port>/
+<i> [webpack-dev-server] On Your Network (IPv4): http://<network-ip-v4>:<port>/
+<i> [webpack-dev-server] On Your Network (IPv6): http://[<network-ip-v6>]:<port>/
+<i> [webpack-dev-server] Content not from webpack is served from '<cwd>/public' directory"
+`;