mdast-util-toc
mdast utility to generate table of contents.
Install
npm:
npm install mdast-util-toc
Use
Dependencies:
var u = require('unist-builder')
var toc = require('mdast-util-toc')
Given a mdast tree:
var tree = u('root', [
u('heading', {depth: 1}, [u('text', 'Alpha')]),
u('heading', {depth: 2}, [u('text', 'Bravo')]),
u('heading', {depth: 3}, [u('text', 'Charlie')]),
u('heading', {depth: 2}, [u('text', 'Delta')])
])
var table = toc(tree)
Yields:
{
index: null,
endIndex: null,
map: {
type: 'list',
ordered: false,
spread: true,
children: [ { type: 'listItem', spread: true, children: [Array] } ]
}
}
API
toc(tree[, options])
Generate a Table of Contents from a tree.
Looks for the first heading matching options.heading
(case insensitive, supports alt/title attributes for links and images too), and returns a table of contents (list) for all following headings. If no heading
is specified, creates a table of contents for all headings in tree
. tree
is not changed.
Links to headings are based on GitHub’s style. Only top-level headings (those not in blockquotes or lists), are used. This default behavior can be changed by passing parents
.
options
options.heading
Heading to look for (string
), wrapped in new RegExp('^(' + value + ')$', 'i')
.
options.maxDepth
Maximum heading depth to include in the table of contents (number
, default: 6
), This is inclusive: when set to 3
, level three headings are included (those with three hashes, ###
).
options.skip
Headings to skip (string
, optional), wrapped in new RegExp('^(' + value + ')$', 'i')
. Any heading matching this expression will not be present in the table of contents.
options.tight
Whether to compile list-items tightly (boolean?
, default: false
).
options.ordered
Whether to compile list-items as an ordered list (boolean?
, default: false
).
options.prefix
Add a prefix to links to headings in the table of contents (string?
, default: null
). Useful for example when later going from mdast to hast and sanitizing with hast-util-sanitize
.
options.parents
Allows headings to be children of certain node types (default: the to toc
given tree
, to only allow top-level headings). Internally, uses unist-util-is to check, so parents
can be any is
-compatible test.
For example, this would allow headings under either root
or blockquote
to be used:
toc(tree, {parents: ['root', 'blockquote']})
Returns
An object representing the table of contents.
Properties
index
(number?
) — Index of the node right after the table of contents heading.-1
if no heading was found,null
if noheading
was givenendIndex
(number?
) — Index of the first node afterheading
that is not part of its section.-1
if no heading was found,null
if noheading
was given, same asindex
if there are no nodes betweenheading
and the first heading in the TOCmap
(Node?
) — List representing the generated table of contents.null
if no table of contents could be created, either because no heading was found or because no following headings were found
Security
Use of mdast-util-toc
does not involve hast, user content, or change the tree, so there are no openings for cross-site scripting (XSS) attacks.
Injecting map
into the syntax tree may open you up to XSS attacks as existing nodes are copied into the table of contents. The following example shows how an existing script is copied into the table of contents.
For the following Markdown:
# Alpha
## Bravo<script>alert(1)</script>
## Charlie
Yields in map
:
- [Alpha](#alpha)
- [Bravo<script>alert(1)</script>](#bravoscriptalert1script)
- [Charlie](#charlie)
Always use hast-util-santize
when transforming to hast.
Related
github-slugger
— Generate a slug just like GitHub doesunist-util-visit
— visit nodesunist-util-visit-parents
— likevisit
, but with a stack of parents
Contribute
See contributing.md
in syntax-tree/.github
for ways to get started. See support.md
for ways to get help.
This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.