Fix a bunch of issues (#30)

Fixes #23
Fixes #24
Fixes #25
Fixes #26
Fixes #27

Author: stroncium

index.js

@@ -68,8 +68,8 @@ const wrapWord = (rows, word, columns) => {
 //
 // 'soft' allows long words to expand past the column length
 const exec = (string, columns, options = {}) => {
-	if (string.trim() === '') {
-		return options.trim === false ? string : string.trim();
+	if (options.trim !== false && string.trim() === '') {
+		return '';
 	}
 
 	let pre = '';
@@ -80,11 +80,13 @@ const exec = (string, columns, options = {}) => {
 	const rows = [''];
 
 	for (const [index, word] of string.split(' ').entries()) {
-		rows[rows.length - 1] = options.trim === false ? rows[rows.length - 1] : rows[rows.length - 1].trim();
+		if (options.trim !== false) {
+			rows[rows.length - 1] = rows[rows.length - 1].trimLeft();
+		}
 		let rowLength = stringWidth(rows[rows.length - 1]);
 
-		if (rowLength || word === '') {
-			if (rowLength === columns && options.wordWrap === false) {
+		if (index !== 0) {
+			if (rowLength === columns && (options.wordWrap === false || options.trim === false)) {
 				// If we start with a new word but the current row length equals the length of the columns, add a new row
 				rows.push('');
 				rowLength = 0;
@@ -96,8 +98,11 @@ const exec = (string, columns, options = {}) => {
 
 		// In 'hard' wrap mode, the length of a line is
 		// never allowed to extend past 'columns'
-		if (lengths[index] > columns && options.hard) {
-			if (rowLength) {
+		if (options.hard && lengths[index] > columns) {
+			const remainingColumns = (columns - rowLength);
+			const breaksStartingThisLine = 1 + Math.floor((lengths[index] - remainingColumns - 1) / columns);
+			const breaksStartingNextLine = Math.floor((lengths[index] - 1) / columns);
+			if (breaksStartingNextLine < breaksStartingThisLine) {
 				rows.push('');
 			}
 			wrapWord(rows, word, columns);

test.js

@@ -53,7 +53,7 @@ test('does not prepend newline if first string is greater than "cols"', t => {
 test('breaks strings longer than "cols" characters', t => {
 	const res5 = m(fixture, 5, {hard: true});
 
-	t.is(res5, 'The\nquick\nbrown\n\u001B[31mfox\u001B[39m\n\u001B[31mjumpe\u001B[39m\n\u001B[31md\u001B[39m\n\u001B[31mover\u001B[39m\n\u001B[31m\u001B[39mthe\nlazy\n\u001B[32mdog\u001B[39m\n\u001B[32mand\u001B[39m\n\u001B[32mthen\u001B[39m\n\u001B[32mran\u001B[39m\n\u001B[32maway\u001B[39m\n\u001B[32mwith\u001B[39m\n\u001B[32mthe\u001B[39m\n\u001B[32munico\u001B[39m\n\u001B[32mrn.\u001B[39m');
+	t.is(res5, 'The\nquick\nbrown\n\u001B[31mfox j\u001B[39m\n\u001B[31mumped\u001B[39m\n\u001B[31mover\u001B[39m\n\u001B[31m\u001B[39mthe\nlazy\n\u001B[32mdog\u001B[39m\n\u001B[32mand\u001B[39m\n\u001B[32mthen\u001B[39m\n\u001B[32mran\u001B[39m\n\u001B[32maway\u001B[39m\n\u001B[32mwith\u001B[39m\n\u001B[32mthe\u001B[39m\n\u001B[32munico\u001B[39m\n\u001B[32mrn.\u001B[39m');
 	t.true(stripAnsi(res5).split('\n').every(x => x.length <= 5));
 });
 
@@ -113,3 +113,32 @@ test('supports unicode surrogate pairs', t => {
 	t.is(m('a\uD83C\uDE00bc', 2, {hard: true}), 'a\n\uD83C\uDE00\nbc');
 	t.is(m('a\uD83C\uDE00bc\uD83C\uDE00d\uD83C\uDE00', 2, {hard: true}), 'a\n\uD83C\uDE00\nbc\n\uD83C\uDE00\nd\n\uD83C\uDE00');
 });
+
+test('#23, properly wraps whitespace with no trimming', t => {
+	t.is(m('   ', 2, {trim: false}), '  \n ');
+	t.is(m('   ', 2, {trim: false, hard: true}), '  \n ');
+});
+
+test('#24, trims leading and trailing whitespace only on actual wrapped lines and only with trimming', t => {
+	t.is(m('   foo   bar   ', 6), 'foo\nbar');
+	t.is(m('   foo   bar   ', 42), 'foo   bar');
+	t.is(m('   foo   bar   ', 42, {trim: false}), '   foo   bar   ');
+});
+
+test('#25, properly wraps whitespace between words with no trimming', t => {
+	t.is(m('foo bar', 3), 'foo\nbar');
+	t.is(m('foo bar', 3, {hard: true}), 'foo\nbar');
+	t.is(m('foo bar', 3, {trim: false}), 'foo\n \nbar');
+	t.is(m('foo bar', 3, {trim: false, hard: true}), 'foo\n \nbar');
+});
+
+test('#26, does not multiplicate leading spaces with no trimming', t => {
+	t.is(m(' a ', 10, {trim: false}), ' a ');
+	t.is(m('   a ', 10, {trim: false}), '   a ');
+});
+
+test('#27, does not remove spaces in line with ansi escapes when no trimming', t => {
+	t.is(m(chalk.bgGreen(` ${chalk.black('OK')} `), 100, {trim: false}), chalk.bgGreen(` ${chalk.black('OK')} `));
+	t.is(m(chalk.bgGreen(`  ${chalk.black('OK')} `), 100, {trim: false}), chalk.bgGreen(`  ${chalk.black('OK')} `));
+	t.is(m(chalk.bgGreen(' hello '), 10, {hard: true, trim: false}), chalk.bgGreen(' hello '));
+});