Frontmatter indent

[sugarshin]

Hi,

I need detect mixed indent with tab in Frontmatter. Is there a way?

[wooorm]

Could you provide examples of ok and not ok input?

[sugarshin]

fail ❌

---
user:
  name: sugarshin
	url: github.com/sugarshin
---

ok ✅

---
user:
  name: sugarshin
  url: github.com/sugarshin
---

Do you understand?

[wooorm]

This depends on what front matter you use. remark-frontmatter can help detect the front matter, but as so many different flavours exist (yaml, toml, and JSON), I don’t think the core of remark-lint should support this.

However, it is of course definitely possible to create external rules.

For example, to check if the YAML is valid, something like this may work (not tested):

var rule = require('unified-lint-rule');
var visit = require('unist-util-visit');
var generated = require('unist-util-generated');
var yaml = require('js-yaml');

module.exports = rule('remark-lint:yaml', yaml);

function yaml(ast, file) {
  visit(ast, 'yaml', visitor);

  function visitor(node) {
    if (!generated(node)) {
      try {
        yaml.safeLoad(node.value);
      } catch (err) {
        file.message(err, node)
      }
    }
  }
}

I’m closing this in favour of remarkjs/ideas#3. If someone would like to work on this, comment there!

[kachkaev]

Why does linter visit the yaml node that remark-frontmatter creates? Was not it supposed to be skipped?

[wooorm]

In the above example, it is created by remark-frontmatter, and checked by the above code?