fix(@angular/cli): on postinstall show a message if using an old version of CLI

Fix #10258

packages/@angular/cli/bin/ng-update-message.js

@@ -0,0 +1,43 @@
+#!/usr/bin/env node
+'use strict';
+
+// Check if the current directory contains '.angular-cli.json'. If it does, show a message to the user that they
+// should use the migration script.
+
+const fs = require('fs');
+const path = require('path');
+
+
+let found = false;
+let current = path.dirname(path.dirname(__dirname));
+while (current !== path.dirname(current)) {
+  if (fs.existsSync(path.join(current, 'angular-cli.json'))
+      || fs.existsSync(path.join(current, '.angular-cli.json'))) {
+    found = true;
+    break;
+  }
+  if (fs.existsSync(path.join(current, 'angular.json'))
+      || fs.existsSync(path.join(current, '.angular.json'))
+      || fs.existsSync(path.join(current, 'package.json'))) {
+    break;
+  }
+
+  current = path.dirname(current);
+}
+
+
+if (found) {
+  // ------------------------------------------------------------------------------------------
+  // If changing this message, please update the same message in
+  // `packages/@angular/cli/models/command-runner.ts`
+
+  // eslint-disable-next-line no-console
+  console.error(`\u001b[31m
+    ${'='.repeat(80)}
+    An old CLI configuration has been detected, which needs to be updated to the latest version.
+
+    Please run the following command to update this workspace:
+      ng update @angular/cli --migrate-only --from=1
+    ${'='.repeat(80)}
+    \u001b[39m`.replace(/^ {4}/gm, ''));
+}

packages/@angular/cli/models/command-runner.ts

@@ -298,13 +298,14 @@ function verifyWorkspace(command: Command, executionScope: CommandScope, root: s
 
     // If an old configuration file is found, throw an exception.
     if (oldConfigFilePath) {
+      // ------------------------------------------------------------------------------------------
+      // If changing this message, please update the same message in
+      // `packages/@angular/cli/bin/ng-update-message.js`
       throw new SilentError(tags.stripIndent`
-        An old project has been detected, which needs to be updated to Angular CLI 6.
+        An old CLI configuration has been detected, which needs to be updated to the latest version.
 
-        Please run the following commands to update this project.
-
-          ng update @angular/cli --migrate-only --from=1.7.1
-          npm i
+        Please run the following command to update this workspace:
+          ng update @angular/cli --migrate-only --from=1
       `);
     }
 

packages/@angular/cli/package.json

@@ -12,6 +12,9 @@
     "angular-cli",
     "Angular CLI"
   ],
+  "scripts": {
+    "postinstall": "node ./bin/ng-update-message.js"
+  },
   "repository": {
     "type": "git",
     "url": "https://github.com/angular/angular-cli.git"