Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 12 additions & 2 deletions doc/api/util.md
Original file line number Diff line number Diff line change
Expand Up @@ -1800,7 +1800,8 @@ console.log(util.stripVTControlCharacters('\u001B[4mvalue\u001B[0m'));
added: v21.7.0
-->

* `format` {string} A text format defined in `util.inspect.colors`.
* `format` {string | Array} A text format or an Array
of text formats defined in `util.inspect.colors`.
* `text` {string} The text to to be formatted.

This function returns a formatted text considering the `format` passed.
Expand All @@ -1822,7 +1823,16 @@ console.log(errorMessage);

```cjs
console.log(
util.styleText('underline', util.styleText('italic', 'My italic underlined message')),
util.styleText(['underline', 'italic'], 'My italic underlined message'),
);
```

When passing an array of formats, the order of the format applied
is left to right so the following style might overwrite the previous one.

```cjs
console.log(
util.styleText(['red', 'green'], 'text'), // green
);
```

Expand Down
27 changes: 25 additions & 2 deletions lib/util.js
Original file line number Diff line number Diff line change
Expand Up @@ -199,17 +199,40 @@ function pad(n) {
}

/**
* @param {string} format
* @param {string} code
* @returns {string}
*/
function escapeStyleCode(code) {
return `\u001b[${code}m`;
}

/**
* @param {string | string[]} format
* @param {string} text
* @returns {string}
*/
function styleText(format, text) {
validateString(text, 'text');
if (ArrayIsArray(format)) {
let left = '';
let right = '';
for (const key of format) {
const formatCodes = inspect.colors[key];
if (formatCodes == null) {
validateOneOf(key, 'format', ObjectKeys(inspect.colors));
}
left += escapeStyleCode(formatCodes[0]);
right = `${escapeStyleCode(formatCodes[1])}${right}`;
}

return `${left}${text}${right}`;
}

const formatCodes = inspect.colors[format];
if (formatCodes == null) {
validateOneOf(format, 'format', ObjectKeys(inspect.colors));
}
return `\u001b[${formatCodes[0]}m${text}\u001b[${formatCodes[1]}m`;
return `${escapeStyleCode(formatCodes[0])}${text}${escapeStyleCode(formatCodes[1])}`;
}

const months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep',
Expand Down
10 changes: 9 additions & 1 deletion test/parallel/test-util-styletext.js
Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,6 @@ const util = require('util');
Symbol(),
() => {},
{},
[],
].forEach((invalidOption) => {
assert.throws(() => {
util.styleText(invalidOption, 'test');
Expand All @@ -33,3 +32,12 @@ assert.throws(() => {
});

assert.strictEqual(util.styleText('red', 'test'), '\u001b[31mtest\u001b[39m');

assert.strictEqual(util.styleText(['bold', 'red'], 'test'), '\u001b[1m\u001b[31mtest\u001b[39m\u001b[22m');
assert.strictEqual(util.styleText(['bold', 'red'], 'test'), util.styleText('bold', util.styleText('red', 'test')));

assert.throws(() => {
util.styleText(['invalid'], 'text');
}, {
code: 'ERR_INVALID_ARG_VALUE',
});