fix: check webpack installation before running cli

packages/package-utils/package.json

@@ -44,6 +44,9 @@
     "@types/cross-spawn": "6.0.1"
   },
   "peerDependenciesMeta": {
+    "webpack": {
+      "optional": true
+    },
     "@webpack-cli/info": {
       "optional": true
     },

packages/webpack-cli/bin/cli.js

@@ -4,13 +4,22 @@
 require('v8-compile-cache');
 const importLocal = require('import-local');
 const runCLI = require('../lib/bootstrap');
+const { yellow } = require('colorette');
+const { error } = require('../lib/utils/logger');
+const { packageExists, promptInstallation } = require('@webpack-cli/package-utils');
 
 // Prefer the local installation of webpack-cli
 if (importLocal(__filename)) {
     return;
 }
 process.title = 'webpack';
 
-const [, , ...rawArgs] = process.argv;
-
-runCLI(rawArgs);
+if (packageExists('webpack')) {
+    const [, , ...rawArgs] = process.argv;
+    runCLI(rawArgs);
+} else {
+    promptInstallation('webpack', () => {
+        error(`It looks like ${yellow('webpack')} is not installed.`);
+    });
+    return;
+}

packages/webpack-cli/lib/utils/Compiler.js

@@ -1,4 +1,5 @@
-const webpack = require('webpack');
+const { packageExists } = require('@webpack-cli/package-utils');
+const webpack = packageExists('webpack') ? require('webpack') : undefined;
 const logger = require('./logger');
 const bailAndWatchWarning = require('./warnings/bailAndWatchWarning');
 const { CompilerOutput } = require('./CompilerOutput');

packages/webpack-cli/lib/utils/cli-flags.js

@@ -1,4 +1,5 @@
-const { cli } = require('webpack');
+const { packageExists } = require('@webpack-cli/package-utils');
+const cli = packageExists('webpack') ? require('webpack').cli : undefined;
 
 const HELP_GROUP = 'help';
 const CONFIG_GROUP = 'config';