fix(core): custom generators help should print relevant information

e2e/nx-misc/src/workspace.test.ts

@@ -24,9 +24,7 @@ describe('Workspace Tests', () => {
     proj = newProject();
   });
 
-  afterAll(() => {
-    cleanupProject();
-  });
+  afterAll(() => cleanupProject());
 
   describe('@nrwl/workspace:library', () => {
     it('should create a library that can be tested and linted', async () => {
@@ -195,6 +193,10 @@ describe('Workspace Tests', () => {
         type: 'boolean',
         description: 'skip changes to tsconfig',
       };
+      json.properties['inlineprop'] = json.properties['name'];
+      json.required = ['inlineprop'];
+      delete json.properties['name'];
+
       updateFile(
         `tools/generators/${custom}/schema.json`,
         JSON.stringify(json)
@@ -205,10 +207,17 @@ describe('Workspace Tests', () => {
         `tools/generators/${custom}/index.ts`,
         indexFile.replace(
           'name: schema.name',
-          'name: schema.name, directory: schema.directory, skipTsConfig: schema.skipTsConfig'
+          'name: schema.inlineprop, directory: schema.directory, skipTsConfig: schema.skipTsConfig'
         )
       );
 
+      const helpOutput = runCLI(`workspace-generator ${custom} --help`);
+      expect(helpOutput).toContain(
+        `workspace-generator ${custom} [inlineprop] (options)`
+      );
+      expect(helpOutput).toContain(`--directory`);
+      expect(helpOutput).toContain(`--skipTsConfig`);
+
       const workspace = uniq('workspace');
       const dryRunOutput = runCLI(
         `workspace-generator ${custom} ${workspace} --no-interactive --directory=dir --skipTsConfig=true -d`
@@ -218,11 +227,10 @@ describe('Workspace Tests', () => {
         `CREATE libs/dir/${workspace}/src/index.ts`
       );
 
-      const output = runCLI(
+      runCLI(
         `workspace-generator ${custom} ${workspace} --no-interactive --directory=dir`
       );
       checkFilesExist(`libs/dir/${workspace}/src/index.ts`);
-      expect(output).not.toContain('UPDATE nx.json');
 
       const jsonFailing = readJson(`tools/generators/${failing}/schema.json`);
       jsonFailing.properties = {};

packages/nx/src/command-line/nx-commands.ts

@@ -256,15 +256,10 @@ export const commandsObject = yargs
     aliases: ['workspace-schematic [name]'],
     builder: async (yargs) =>
       linkToNxDevAndExamples(
-        await withWorkspaceGeneratorOptions(yargs),
+        await withWorkspaceGeneratorOptions(yargs, process.argv.slice(3)),
         'workspace-generator'
       ),
-    handler: async () => {
-      await (
-        await import('./workspace-generators')
-      ).workspaceGenerators(process.argv.slice(3));
-      process.exit(0);
-    },
+    handler: workspaceGeneratorHandler,
   })
   .command({
     command: 'migrate [packageAndVersion]',
@@ -749,27 +744,130 @@ function withRunOneOptions(yargs: yargs.Argv) {
   }
 }
 
-async function withWorkspaceGeneratorOptions(yargs: yargs.Argv) {
-  yargs
-    .option('list-generators', {
-      describe: 'List the available workspace-generators',
-      type: 'boolean',
-    })
-    .positional('name', {
-      type: 'string',
-      describe: 'The name of your generator',
-    });
+type WorkspaceGeneratorProperties = {
+  [name: string]:
+    | {
+        type: yargs.Options['type'];
+        description?: string;
+        default?: any;
+        enum?: yargs.Options['type'][];
+      }
+    | {
+        type: yargs.PositionalOptionsType;
+        description?: string;
+        default?: any;
+        enum?: yargs.PositionalOptionsType[];
+        $default: {
+          $source: 'argv';
+          index: number;
+        };
+      };
+};
+
+function isPositionalProperty(
+  property: WorkspaceGeneratorProperties[keyof WorkspaceGeneratorProperties]
+): property is { type: yargs.PositionalOptionsType } {
+  return property['$default']?.['$source'] === 'argv';
+}
 
-  /**
-   * Don't require `name` if only listing available
-   * schematics
-   */
-  if ((await yargs.argv).listGenerators !== true) {
-    yargs.demandOption('name');
+async function withWorkspaceGeneratorOptions(
+  yargs: yargs.Argv,
+  args: string[]
+) {
+  // filter out only positional arguments
+  args = args.filter((a) => !a.startsWith('-'));
+  if (args.length) {
+    // this is an actual workspace generator
+    return withCustomGeneratorOptions(yargs, args[0]);
+  } else {
+    yargs
+      .option('list-generators', {
+        describe: 'List the available workspace-generators',
+        type: 'boolean',
+      })
+      .positional('name', {
+        type: 'string',
+        describe: 'The name of your generator',
+      });
+    /**
+     * Don't require `name` if only listing available
+     * schematics
+     */
+    if ((await yargs.argv).listGenerators !== true) {
+      yargs.demandOption('name');
+    }
+    return yargs;
   }
+}
+
+async function withCustomGeneratorOptions(
+  yargs: yargs.Argv,
+  generatorName: string
+) {
+  const schema = (
+    await import('./workspace-generators')
+  ).workspaceGeneratorSchema(generatorName);
+  const options = [];
+  const positionals = [];
+
+  Object.entries(schema.properties as WorkspaceGeneratorProperties).forEach(
+    ([name, prop]) => {
+      options.push({
+        name,
+        definition: {
+          describe: prop.description,
+          type: prop.type,
+          default: prop.default,
+          choices: prop.enum,
+        },
+      });
+      if (isPositionalProperty(prop)) {
+        positionals.push({
+          name,
+          definition: {
+            describe: prop.description,
+            type: prop.type,
+            choices: prop.enum,
+          },
+        });
+      }
+    }
+  );
+
+  let command = generatorName;
+  positionals.forEach(({ name }) => {
+    command += ` [${name}]`;
+  });
+  if (options.length) {
+    command += ' (options)';
+  }
+
+  yargs.command({
+    // this is the default and only command
+    command,
+    describe: schema.description || '',
+    builder: (y) => {
+      options.forEach(({ name, definition }) => {
+        y.option(name, definition);
+      });
+      positionals.forEach(({ name, definition }) => {
+        y.positional(name, definition);
+      });
+      return linkToNxDevAndExamples(y, 'workspace-generator');
+    },
+    handler: workspaceGeneratorHandler,
+  });
+
   return yargs;
 }
 
+async function workspaceGeneratorHandler() {
+  await (
+    await import('./workspace-generators')
+  ).workspaceGenerators(process.argv.slice(3));
+  process.exit(0);
+}
+
 function withMigrationOptions(yargs: yargs.Argv) {
   const defaultCommitPrefix = 'chore: [nx migration] ';
 

packages/nx/src/command-line/workspace-generators.ts

@@ -40,6 +40,17 @@ export async function workspaceGenerators(args: string[]) {
   }
 }
 
+export function workspaceGeneratorSchema(name: string) {
+  const schemaFile = path.join(generatorsDir, name, 'schema.json');
+
+  if (fileExists(schemaFile)) {
+    return readJsonFile(schemaFile);
+  } else {
+    logger.error(`Cannot find schema for ${name}. Does the generator exist?`);
+    process.exit(1);
+  }
+}
+
 // compile tools
 function compileTools() {
   const toolsOutDir = getToolsOutDir();