Wrap and indent help descriptions for options and commands

Co-authored-by: Ephigenia <love@ephigenia.de>

index.js

@@ -1153,11 +1153,16 @@ Command.prototype.padWidth = function() {
 Command.prototype.optionHelp = function() {
   var width = this.padWidth();
 
+  var columns = process.stdout.columns || 80;
+  var descriptionWidth = columns - width - 4;
+  var minWidth = 40;
+
   // Append the help information
   return this.options.map(function(option) {
-    return pad(option.flags, width) + '  ' + option.description +
+    const fullDesc = option.description +
       ((!option.negate && option.defaultValue !== undefined) ? ' (default: ' + JSON.stringify(option.defaultValue) + ')' : '');
-  }).concat([pad(this._helpFlags, width) + '  ' + this._helpDescription])
+    return pad(option.flags, width) + '  ' + optionalWrap(fullDesc, descriptionWidth, width + 2, minWidth);
+  }).concat([pad(this._helpFlags, width) + '  ' + optionalWrap(this._helpDescription, descriptionWidth, width + 2, minWidth)])
     .join('\n');
 };
 
@@ -1174,11 +1179,15 @@ Command.prototype.commandHelp = function() {
   var commands = this.prepareCommands();
   var width = this.padWidth();
 
+  var columns = process.stdout.columns || 80;
+  var descriptionWidth = columns - width - 4;
+  var minWidth = 40;
+
   return [
     'Commands:',
     commands.map(function(cmd) {
       var desc = cmd[1] ? '  ' + cmd[1] : '';
-      return (desc ? pad(cmd[0], width) : cmd[0]) + desc;
+      return (desc ? pad(cmd[0], width) : cmd[0]) + optionalWrap(desc, descriptionWidth, width + 2, minWidth);
     }).join('\n').replace(/^/gm, '  '),
     ''
   ].join('\n');
@@ -1202,10 +1211,12 @@ Command.prototype.helpInformation = function() {
     var argsDescription = this._argsDescription;
     if (argsDescription && this._args.length) {
       var width = this.padWidth();
+      var columns = process.stdout.columns || 80;
+      var descriptionWidth = columns - width - 5;
       desc.push('Arguments:');
       desc.push('');
       this._args.forEach(function(arg) {
-        desc.push('  ' + pad(arg.name, width) + '  ' + argsDescription[arg.name]);
+        desc.push('  ' + pad(arg.name, width) + '  ' + wrap(argsDescription[arg.name], descriptionWidth, width + 4));
       });
       desc.push('');
     }
@@ -1329,6 +1340,48 @@ function pad(str, width) {
   return str + Array(len + 1).join(' ');
 }
 
+/**
+ * Wraps the given string with line breaks at the specified width while breaking
+ * words and indenting every but the first line on the left.
+ *
+ * @param {String} str
+ * @param {Number} width
+ * @param {Number} indent
+ * @return {String}
+ * @api private
+ */
+function wrap(str, width, indent) {
+  var regex = new RegExp('.{1,' + (width - 1) + '}([\\s\u200B]|$)|[^\\s\u200B]+?([\\s\u200B]|$)', 'g');
+  var lines = str.match(regex) || [];
+  var result = lines.map(function(line, i) {
+    if (line.slice(-1) === '\n') {
+      line = line.slice(0, line.length - 1);
+    }
+    return ((i > 0 && indent) ? Array(indent + 1).join(' ') : '') + line;
+  }).join('\n');
+  return result;
+}
+
+/**
+ * Optionally wrap the given str to a max width of width characters per line
+ * while indenting with indent spaces. Do not wrap the text when the minWidth
+ * is not hit.
+ *
+ * @param {String} str
+ * @param {Number} width
+ * @param {Number} indent
+ * @return {String}
+ * @api private
+ */
+function optionalWrap(str, width, indent, minWidth) {
+  // detected manually wrapped and indented strings by searching for line breaks
+  // followed by multiple spaces/tabs
+  if (str.match(/[\n]\s+/)) return str;
+  // check if minimum width is reached
+  if (width < minWidth) return str;
+  return wrap(str, width, indent);
+}
+
 /**
  * Output help information if necessary
  *

tests/helpwrap.test.js

@@ -0,0 +1,123 @@
+const commander = require('../');
+
+// Test auto wrap and indent with some manual strings.
+
+test('when long option description then wrap and indent', () => {
+  const oldColumns = process.stdout.columns;
+  process.stdout.columns = 80;
+  const program = new commander.Command();
+  program
+    .option('-x -extra-long-option-switch', 'kjsahdkajshkahd kajhsd akhds kashd kajhs dkha dkh aksd ka dkha kdh kasd ka kahs dkh sdkh askdh aksd kashdk ahsd kahs dkha skdh');
+
+  const expectedOutput =
+`Usage:  [options]
+
+Options:
+  -x -extra-long-option-switch  kjsahdkajshkahd kajhsd akhds kashd kajhs dkha 
+                                dkh aksd ka dkha kdh kasd ka kahs dkh sdkh 
+                                askdh aksd kashdk ahsd kahs dkha skdh
+  -h, --help                    output usage information
+`;
+
+  expect(program.helpInformation()).toBe(expectedOutput);
+  process.stdout.columns = oldColumns;
+});
+
+test('when long option description and default then wrap and indent', () => {
+  const oldColumns = process.stdout.columns;
+  process.stdout.columns = 80;
+  const program = new commander.Command();
+  program
+    .option('-x -extra-long-option <value>', 'kjsahdkajshkahd kajhsd akhds', 'aaa bbb ccc ddd eee fff ggg');
+
+  const expectedOutput =
+`Usage:  [options]
+
+Options:
+  -x -extra-long-option <value>  kjsahdkajshkahd kajhsd akhds (default: "aaa 
+                                 bbb ccc ddd eee fff ggg")
+  -h, --help                     output usage information
+`;
+
+  expect(program.helpInformation()).toBe(expectedOutput);
+  process.stdout.columns = oldColumns;
+});
+
+test('when long command description then wrap and indent', () => {
+  const oldColumns = process.stdout.columns;
+  process.stdout.columns = 80;
+  const program = new commander.Command();
+  program
+    .option('-x -extra-long-option-switch', 'x')
+    .command('alpha', 'Lorem mollit quis dolor ex do eu quis ad insa a commodo esse.');
+
+  const expectedOutput =
+`Usage:  [options] [command]
+
+Options:
+  -x -extra-long-option-switch  x
+  -h, --help                    output usage information
+
+Commands:
+  alpha                         Lorem mollit quis dolor ex do eu quis ad insa 
+                                a commodo esse.
+`;
+
+  expect(program.helpInformation()).toBe(expectedOutput);
+  process.stdout.columns = oldColumns;
+});
+
+test('when not enough room then help not wrapped', () => {
+  // Not wrapping if less than 40 columns available for wrapping.
+  const oldColumns = process.stdout.columns;
+  process.stdout.columns = 60;
+  const program = new commander.Command();
+  const commandDescription = 'description text of very long command which should not be automatically be wrapped. Do fugiat eiusmod ipsum laboris excepteur pariatur sint ullamco tempor labore eu.';
+  program
+    .command('1234567801234567890x', commandDescription);
+
+  const expectedOutput =
+`Usage:  [options] [command]
+
+Options:
+  -h, --help            output usage information
+
+Commands:
+  1234567801234567890x  ${commandDescription}
+`;
+
+  expect(program.helpInformation()).toBe(expectedOutput);
+  process.stdout.columns = oldColumns;
+});
+
+test('when option descripton preformatted then only add small indent', () => {
+  const oldColumns = process.stdout.columns;
+  process.stdout.columns = 80;
+  // #396: leave custom format alone, apart from space-space indent
+  const optionSpec = '-t, --time <HH:MM>';
+  const program = new commander.Command();
+  program
+    .option(optionSpec,
+`select time
+
+Time can also be specified using special values:
+  "dawn" - From night to sunrise.
+`);
+
+  const expectedOutput =
+`Usage:  [options]
+
+Options:
+  ${optionSpec}  select time
+  
+  Time can also be specified using special values:
+    "dawn" - From night to sunrise.
+  
+  -h, --help          output usage information
+`;
+
+  expect(program.helpInformation()).toBe(expectedOutput);
+  process.stdout.columns = oldColumns;
+});
+
+// test for argsDescription passed to command ????