refactor(@angular/cli): add more actionable missing lint target message

Author: alan-agius4

packages/angular/cli/commands/deploy-impl.ts

@@ -5,12 +5,11 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import { ArchitectCommand, ArchitectCommandOptions } from '../models/architect-command';
+import { ArchitectCommand } from '../models/architect-command';
 import { Arguments } from '../models/interface';
 import { Schema as DeployCommandSchema } from './deploy';
 
 const BuilderMissing = `
-
 Cannot find "deploy" target for the specified project.
 
 You should add a package that implements deployment capabilities for your

packages/angular/cli/commands/lint-impl.ts

@@ -5,15 +5,27 @@
  * Use of this source code is governed by an MIT-style license that can be
  * found in the LICENSE file at https://angular.io/license
  */
-import { ArchitectCommand, ArchitectCommandOptions } from '../models/architect-command';
+import { ArchitectCommand } from '../models/architect-command';
 import { Arguments } from '../models/interface';
 import { Schema as LintCommandSchema } from './lint';
 
+const MissingBuilder = `
+Cannot find "lint" target for the specified project.
+
+You should add a package that implements linting capabilities.
+
+For example:
+  ng add @angular-eslint/schematics
+`;
+
 export class LintCommand extends ArchitectCommand<LintCommandSchema> {
-  public readonly target = 'lint';
-  public readonly multiTarget = true;
+  readonly target = 'lint';
+  readonly multiTarget = true;
+  readonly missingTargetError = MissingBuilder;
 
-  public async run(options: ArchitectCommandOptions & Arguments) {
-    return this.runArchitectTarget(options);
+  async initialize(options: LintCommandSchema & Arguments): Promise<number | void> {
+    if (!options.help) {
+      return super.initialize(options);
+    }
   }
 }

packages/angular/cli/commands/lint-long.md

@@ -1,7 +1,20 @@
-Takes the name of the project, as specified in the  `projects` section of the `angular.json` workspace configuration file.
-When a project name is not supplied, it will execute for all projects.
+The command takes an optional project name, as specified in the `projects` section of the `angular.json` workspace configuration file.
+When a project name is not supplied, executes the `lint` builder for the default project.
 
-The default linting tool is [TSLint](https://palantir.github.io/tslint/), and the default configuration is specified in the project's `tslint.json` file.
+To use the `ng lint` command, use `ng add` to add a package that implements linting capabilities. Adding the package automatically updates your workspace configuration, adding a lint [CLI builder](guide/cli-builder).
+For example:
 
-**Note**: TSLint has been discontinued and support has been deprecated in the Angular CLI. The options shown below are for the deprecated TSLint builder.
-To opt-in using the community driven ESLint builder, see [angular-eslint](https://github.com/angular-eslint/angular-eslint#migrating-an-angular-cli-project-from-codelyzer-and-tslint) README.
+```json
+"projects": {
+  "my-project": {
+    ...
+    "architect": {
+      ...
+      "lint": {
+        "builder": "@angular-eslint/builder:lint",
+        "options": {}
+      }
+    }
+  }
+}
+ ```

packages/angular/cli/commands/lint.json

@@ -4,7 +4,7 @@
   "description": "Runs linting tools on Angular app code in a given project folder.",
   "$longDescription": "./lint-long.md",
 
-  "$aliases": [ "l" ],
+  "$aliases": ["l"],
   "$scope": "in",
   "$type": "architect",
   "$impl": "./lint-impl#LintCommand",
@@ -22,15 +22,14 @@
           }
         },
         "configuration": {
-          "description": "The linting configuration to use.",
+          "description": "One or more named builder configurations as a comma-separated list as specified in the \"configurations\" section of angular.json.\nThe builder uses the named configurations to run the given target.\nFor more information, see https://angular.io/guide/workspace-config#alternate-build-configurations.",
           "type": "string",
           "aliases": [
             "c"
           ]
         }
       },
-      "required": [
-      ]
+      "required": []
     },
     {
       "$ref": "./definitions.json#/definitions/base"