prettier-js-comments

A Prettier plugin that reflows /** ... */ doc comment blocks in JavaScript and TypeScript files to respect printWidth. All other formatting is delegated to Prettier's built-in parsers and printers.

Install

pnpm add -D prettier prettier-js-comments

Usage

Add the plugin to your Prettier config:

{
  "plugins": ["prettier-js-comments"],
  "printWidth": 80
}

Then format files as usual:

pnpm prettier --write "**/*.{js,jsx,ts,tsx}"

What it does

Given a file like this with printWidth: 40:

/**
 * This is a long doc comment that is too wide for the configured print width and will be reflowed.
 */
function foo() {}

The plugin rewrites the comment to:

/**
 * This is a long doc comment that is
 * too wide for the configured print
 * width and will be reflowed.
 */
function foo() {}

A single-line doc comment that exceeds printWidth is expanded to multiline:

/** This is a long doc comment that exceeds the print width. */

Becomes:

/**
 * This is a long doc comment that
 * exceeds the print width.
 */

Rules

• Only /** ... */ doc comment blocks are touched. Regular block comments (/* */) and line comments (//) are left alone.
• The /** must be the only content on its line. Inline doc comments after code are not modified.
• If any JSDoc tag (@param, @returns, etc.) is present in the block, the entire block is skipped.
• Consecutive text lines inside a doc comment are joined and reflowed together as one paragraph.
• The indent of the opening /** line is used for the reflowed output.
• printWidth is measured from column 0, so a deeper indent yields a narrower reflowed width.
• A bare * line inside a doc comment is a paragraph break.
• Separators (* ----), bullets (* - item), and indented content (code examples) are emitted verbatim and act as paragraph boundaries.
• Words are never broken. A word longer than the available width overflows its line.

License

MIT