Add suppressWarnings() for warnings in tj#1915 tj#1917 tj#1931 tj#1938 …

…tj#1940

Motivation:
tj#1940 (comment)

lib/command.js

@@ -57,6 +57,7 @@ class Command extends EventEmitter {
     this._showHelpAfterError = false;
     this._showSuggestionAfterError = true;
 
+    this._suppressWarnings = false;
     // see .configureOutput() for docs
     this._outputConfiguration = {
       writeOut: (str) => process.stdout.write(str),
@@ -88,6 +89,7 @@ class Command extends EventEmitter {
    * @return {Command} `this` command for chaining
    */
   copyInheritedSettings(sourceCommand) {
+    this._suppressWarnings = sourceCommand._suppressWarnings;
     this._outputConfiguration = sourceCommand._outputConfiguration;
     this._hasHelpOption = sourceCommand._hasHelpOption;
     this._helpFlags = sourceCommand._helpFlags;
@@ -109,6 +111,19 @@ class Command extends EventEmitter {
     return this;
   }
 
+  /**
+   * Suppress warnings about library usage patterns that are not always wrong
+   * but are often connected with a developer mistake,
+   * or a different pattern better suited for the use case scenario is offered.
+   *
+   * @param {boolean} [suppress=true]
+   * @return {Command} `this` command for chaining
+   */
+  suppressWarnings(suppress = true) {
+    this._suppressWarnings = !!suppress;
+    return this;
+  }
+
   /**
    * Define a command.
    *

tests/command.chain.test.js

@@ -4,6 +4,12 @@ const { Command, Option, Argument } = require('../');
 // parse and parseAsync are tested in command.parse.test.js
 
 describe('Command methods that should return this for chaining', () => {
+  test('when call .suppressWarnings() then returns this', () => {
+    const program = new Command();
+    const result = program.suppressWarnings();
+    expect(result).toBe(program);
+  });
+
   test('when call .command() with description for stand-alone executable then returns this', () => {
     const program = new Command();
     const result = program.command('foo', 'foo description');

typings/index.d.ts

@@ -285,6 +285,15 @@ export class Command {
 
   constructor(name?: string);
 
+  /**
+   * Suppress warnings about library usage patterns that are not always wrong
+   * but are often connected with a developer mistake,
+   * or a different pattern better suited for the use case scenario is offered.
+   *
+   * @return {Command} `this` command for chaining
+   */
+  suppressWarnings(suppress?: boolean): this;
+
   /**
    * Set the program version to `str`.
    *

typings/index.test-d.ts

@@ -32,6 +32,10 @@ expectType<readonly commander.Command[]>(program.commands);
 expectType<readonly commander.Option[]>(program.options);
 expectType<commander.Command | null>(program.parent);
 
+// suppressWarnings
+expectType<commander.Command>(program.suppressWarnings());
+expectType<commander.Command>(program.suppressWarnings(false));
+
 // version
 expectType<commander.Command>(program.version('1.2.3'));
 expectType<commander.Command>(program.version('1.2.3', '-r,--revision'));