[ts-command-line] Add ScopedCommandLineAction class

common/changes/@rushstack/ts-command-line/user-danade-ScopedCommandLine_2022-04-21-22-00.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/ts-command-line",
+      "comment": "Add ScopedCommandLineAction class, which allows for the creation of actions that have variable arguments based on the provided scope.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@rushstack/ts-command-line"
+}

common/reviews/api/ts-command-line.api.md

@@ -20,7 +20,7 @@ export abstract class CommandLineAction extends CommandLineParameterProvider {
     protected abstract onDefineParameters(): void;
     protected abstract onExecute(): Promise<void>;
     // @internal
-    _processParsedData(data: _ICommandLineParserData): void;
+    _processParsedData(parserOptions: ICommandLineParserOptions, data: _ICommandLineParserData): void;
     readonly summary: string;
 }
 
@@ -113,6 +113,7 @@ export abstract class CommandLineParameter {
     readonly environmentVariable: string | undefined;
     // @internal
     _getSupplementaryNotes(supplementaryNotes: string[]): void;
+    readonly groupName: string | undefined;
     abstract get kind(): CommandLineParameterKind;
     readonly longName: string;
     // @internal
@@ -148,6 +149,8 @@ export abstract class CommandLineParameterProvider {
     defineFlagParameter(definition: ICommandLineFlagDefinition): CommandLineFlagParameter;
     defineIntegerListParameter(definition: ICommandLineIntegerListDefinition): CommandLineIntegerListParameter;
     defineIntegerParameter(definition: ICommandLineIntegerDefinition): CommandLineIntegerParameter;
+    // @internal (undocumented)
+    protected _defineParameter(parameter: CommandLineParameter): void;
     defineStringListParameter(definition: ICommandLineStringListDefinition): CommandLineStringListParameter;
     defineStringParameter(definition: ICommandLineStringDefinition): CommandLineStringParameter;
     // @internal
@@ -164,9 +167,10 @@ export abstract class CommandLineParameterProvider {
     get parameters(): ReadonlyArray<CommandLineParameter>;
     get parametersProcessed(): boolean;
     // @internal (undocumented)
-    protected _processParsedData(data: _ICommandLineParserData): void;
+    protected _processParsedData(parserOptions: ICommandLineParserOptions, data: _ICommandLineParserData): void;
     get remainder(): CommandLineRemainder | undefined;
     renderHelpText(): string;
+    renderUsageText(): string;
 }
 
 // @public
@@ -249,6 +253,7 @@ export class DynamicCommandLineParser extends CommandLineParser {
 export interface IBaseCommandLineDefinition {
     description: string;
     environmentVariable?: string;
+    parameterGroupName?: string;
     parameterLongName: string;
     parameterShortName?: string;
     required?: boolean;
@@ -306,6 +311,7 @@ export interface _ICommandLineParserData {
 export interface ICommandLineParserOptions {
     enableTabCompletionAction?: boolean;
     toolDescription: string;
+    toolEpilog?: string;
     toolFilename: string;
 }
 
@@ -323,4 +329,23 @@ export interface ICommandLineStringDefinition extends IBaseCommandLineDefinition
 export interface ICommandLineStringListDefinition extends IBaseCommandLineDefinitionWithArgument {
 }
 
+// @public
+export abstract class ScopedCommandLineAction extends CommandLineAction {
+    constructor(options: ICommandLineActionOptions);
+    // @internal (undocumented)
+    protected _defineParameter(parameter: CommandLineParameter): void;
+    // @internal
+    _execute(): Promise<void>;
+    // @internal
+    protected _getScopedCommandLineParser(): CommandLineParser;
+    protected onDefineParameters(): void;
+    protected abstract onDefineScopedParameters(scopedParameterProvider: CommandLineParameterProvider): void;
+    protected abstract onDefineUnscopedParameters(): void;
+    protected abstract onExecute(): Promise<void>;
+    get parameters(): ReadonlyArray<CommandLineParameter>;
+    // @internal
+    _processParsedData(parserOptions: ICommandLineParserOptions, data: _ICommandLineParserData): void;
+    static ScopingParameterGroupName: 'scoping';
+}
+
 ```

libraries/ts-command-line/src/index.ts

@@ -8,6 +8,8 @@
  */
 
 export { CommandLineAction, ICommandLineActionOptions } from './providers/CommandLineAction';
+export { DynamicCommandLineAction } from './providers/DynamicCommandLineAction';
+export { ScopedCommandLineAction } from './providers/ScopedCommandLineAction';
 
 export {
   IBaseCommandLineDefinition,
@@ -43,9 +45,6 @@ export {
 } from './providers/CommandLineParameterProvider';
 
 export { ICommandLineParserOptions, CommandLineParser } from './providers/CommandLineParser';
-
-export { DynamicCommandLineAction } from './providers/DynamicCommandLineAction';
-
 export { DynamicCommandLineParser } from './providers/DynamicCommandLineParser';
 
 export { CommandLineConstants } from './Constants';

libraries/ts-command-line/src/parameters/BaseClasses.ts

@@ -53,6 +53,9 @@ export abstract class CommandLineParameter {
   /** {@inheritDoc IBaseCommandLineDefinition.parameterShortName} */
   public readonly shortName: string | undefined;
 
+  /** {@inheritDoc IBaseCommandLineDefinition.parameterGroupName} */
+  public readonly groupName: string | undefined;
+
   /** {@inheritDoc IBaseCommandLineDefinition.description} */
   public readonly description: string;
 
@@ -69,6 +72,7 @@ export abstract class CommandLineParameter {
   public constructor(definition: IBaseCommandLineDefinition) {
     this.longName = definition.parameterLongName;
     this.shortName = definition.parameterShortName;
+    this.groupName = definition.parameterGroupName;
     this.description = definition.description;
     this.required = !!definition.required;
     this.environmentVariable = definition.environmentVariable;

libraries/ts-command-line/src/parameters/CommandLineDefinition.ts

@@ -17,6 +17,11 @@ export interface IBaseCommandLineDefinition {
    */
   parameterShortName?: string;
 
+  /**
+   * An optional parameter group name, shown when invoking the tool with "--help"
+   */
+  parameterGroupName?: string;
+
   /**
    * Documentation for the parameter that will be shown when invoking the tool with "--help"
    */

libraries/ts-command-line/src/providers/CommandLineAction.ts

@@ -2,7 +2,9 @@
 // See LICENSE in the project root for license information.
 
 import * as argparse from 'argparse';
+
 import { CommandLineParameterProvider, ICommandLineParserData } from './CommandLineParameterProvider';
+import type { ICommandLineParserOptions } from './CommandLineParser';
 
 /**
  * Options for the CommandLineAction constructor.
@@ -90,8 +92,8 @@ export abstract class CommandLineAction extends CommandLineParameterProvider {
    * This is called internally by CommandLineParser.execute()
    * @internal
    */
-  public _processParsedData(data: ICommandLineParserData): void {
-    super._processParsedData(data);
+  public _processParsedData(parserOptions: ICommandLineParserOptions, data: ICommandLineParserData): void {
+    super._processParsedData(parserOptions, data);
   }
 
   /**

libraries/ts-command-line/src/providers/CommandLineParameterProvider.ts

@@ -2,7 +2,8 @@
 // See LICENSE in the project root for license information.
 
 import * as argparse from 'argparse';
-import {
+
+import type {
   ICommandLineChoiceDefinition,
   ICommandLineChoiceListDefinition,
   ICommandLineIntegerDefinition,
@@ -12,6 +13,7 @@ import {
   ICommandLineStringListDefinition,
   ICommandLineRemainderDefinition
 } from '../parameters/CommandLineDefinition';
+import type { ICommandLineParserOptions } from './CommandLineParser';
 import {
   CommandLineParameter,
   CommandLineParameterWithArgument,
@@ -46,6 +48,7 @@ export abstract class CommandLineParameterProvider {
 
   private _parameters: CommandLineParameter[];
   private _parametersByLongName: Map<string, CommandLineParameter>;
+  private _parameterGroupsByName: Map<string, argparse.ArgumentGroup>;
   private _parametersProcessed: boolean;
   private _remainder: CommandLineRemainder | undefined;
 
@@ -54,6 +57,7 @@ export abstract class CommandLineParameterProvider {
   public constructor() {
     this._parameters = [];
     this._parametersByLongName = new Map<string, CommandLineParameter>();
+    this._parameterGroupsByName = new Map<string, argparse.ArgumentGroup>();
     this._parametersProcessed = false;
   }
 
@@ -207,6 +211,7 @@ export abstract class CommandLineParameterProvider {
   public getIntegerListParameter(parameterLongName: string): CommandLineIntegerListParameter {
     return this._getParameter(parameterLongName, CommandLineParameterKind.IntegerList);
   }
+
   /**
    * Defines a command-line parameter whose argument is a single text string.
    *
@@ -297,6 +302,13 @@ export abstract class CommandLineParameterProvider {
     return this._getArgumentParser().formatHelp();
   }
 
+  /**
+   * Generates the command-line usage text.
+   */
+  public renderUsageText(): string {
+    return this._getArgumentParser().formatUsage();
+  }
+
   /**
    * Returns a object which maps the long name of each parameter in this.parameters
    * to the stringified form of its value. This is useful for logging telemetry, but
@@ -349,7 +361,7 @@ export abstract class CommandLineParameterProvider {
   protected abstract _getArgumentParser(): argparse.ArgumentParser;
 
   /** @internal */
-  protected _processParsedData(data: ICommandLineParserData): void {
+  protected _processParsedData(parserOptions: ICommandLineParserOptions, data: ICommandLineParserData): void {
     if (this._parametersProcessed) {
       throw new Error('Command Line Parser Data was already processed');
     }
@@ -367,28 +379,8 @@ export abstract class CommandLineParameterProvider {
     this._parametersProcessed = true;
   }
 
-  private _generateKey(): string {
-    return 'key_' + (CommandLineParameterProvider._keyCounter++).toString();
-  }
-
-  private _getParameter<T extends CommandLineParameter>(
-    parameterLongName: string,
-    expectedKind: CommandLineParameterKind
-  ): T {
-    const parameter: CommandLineParameter | undefined = this._parametersByLongName.get(parameterLongName);
-    if (!parameter) {
-      throw new Error(`The parameter "${parameterLongName}" is not defined`);
-    }
-    if (parameter.kind !== expectedKind) {
-      throw new Error(
-        `The parameter "${parameterLongName}" is of type "${CommandLineParameterKind[parameter.kind]}"` +
-          ` whereas the caller was expecting "${CommandLineParameterKind[expectedKind]}".`
-      );
-    }
-    return parameter as T;
-  }
-
-  private _defineParameter(parameter: CommandLineParameter): void {
+  /** @internal */
+  protected _defineParameter(parameter: CommandLineParameter): void {
     if (this._remainder) {
       throw new Error(
         'defineCommandLineRemainder() was already called for this provider;' +
@@ -455,10 +447,23 @@ export abstract class CommandLineParameterProvider {
         break;
     }
 
-    const argumentParser: argparse.ArgumentParser = this._getArgumentParser();
-    argumentParser.addArgument(names, { ...argparseOptions });
+    let argumentGroup: argparse.ArgumentGroup | undefined;
+    if (parameter.groupName) {
+      argumentGroup = this._parameterGroupsByName.get(parameter.groupName);
+      if (!argumentGroup) {
+        argumentGroup = this._getArgumentParser().addArgumentGroup({
+          title: `Optional ${parameter.groupName} arguments`
+        });
+        this._parameterGroupsByName.set(parameter.groupName, argumentGroup);
+      }
+    } else {
+      argumentGroup = this._getArgumentParser();
+    }
+
+    argumentGroup.addArgument(names, { ...argparseOptions });
+
     if (parameter.undocumentedSynonyms && parameter.undocumentedSynonyms.length > 0) {
-      argumentParser.addArgument(parameter.undocumentedSynonyms, {
+      argumentGroup.addArgument(parameter.undocumentedSynonyms, {
         ...argparseOptions,
         help: argparse.Const.SUPPRESS
       });
@@ -467,4 +472,25 @@ export abstract class CommandLineParameterProvider {
     this._parameters.push(parameter);
     this._parametersByLongName.set(parameter.longName, parameter);
   }
+
+  private _generateKey(): string {
+    return 'key_' + (CommandLineParameterProvider._keyCounter++).toString();
+  }
+
+  private _getParameter<T extends CommandLineParameter>(
+    parameterLongName: string,
+    expectedKind: CommandLineParameterKind
+  ): T {
+    const parameter: CommandLineParameter | undefined = this._parametersByLongName.get(parameterLongName);
+    if (!parameter) {
+      throw new Error(`The parameter "${parameterLongName}" is not defined`);
+    }
+    if (parameter.kind !== expectedKind) {
+      throw new Error(
+        `The parameter "${parameterLongName}" is of type "${CommandLineParameterKind[parameter.kind]}"` +
+          ` whereas the caller was expecting "${CommandLineParameterKind[expectedKind]}".`
+      );
+    }
+    return parameter as T;
+  }
 }

libraries/ts-command-line/src/providers/CommandLineParser.ts

@@ -24,6 +24,12 @@ export interface ICommandLineParserOptions {
    */
   toolDescription: string;
 
+  /**
+   * An optional string to append at the end of the "--help" main page. If not provided, an epilog
+   * will be automatically generated based on the toolFilename.
+   */
+  toolEpilog?: string;
+
   /**
    * Set to true to auto-define a tab completion action. False by default.
    */
@@ -68,7 +74,8 @@ export abstract class CommandLineParser extends CommandLineParameterProvider {
       prog: this._options.toolFilename,
       description: this._options.toolDescription,
       epilog: colors.bold(
-        `For detailed help about a specific command, use: ${this._options.toolFilename} <command> -h`
+        this._options.toolEpilog ??
+          `For detailed help about a specific command, use: ${this._options.toolFilename} <command> -h`
       )
     });
 
@@ -194,19 +201,21 @@ export abstract class CommandLineParser extends CommandLineParameterProvider {
         // 0=node.exe, 1=script name
         args = process.argv.slice(2);
       }
-      if (args.length === 0) {
+      if (this.actions.length > 0 && args.length === 0) {
+        // Parsers that use actions should print help when 0 args are provided. Allow
+        // actionless parsers to continue on zero args.
         this._argumentParser.printHelp();
         return;
       }
 
       const data: ICommandLineParserData = this._argumentParser.parseArgs(args);
 
-      this._processParsedData(data);
+      this._processParsedData(this._options, data);
 
       for (const action of this._actions) {
         if (action.actionName === data.action) {
           this.selectedAction = action;
-          action._processParsedData(data);
+          action._processParsedData(this._options, data);
           break;
         }
       }