Validates rendered HTML strings with explicit checks.

validate_html/2 parses the rendered HTML once, runs the checks you choose, and returns :ok or {:error, issues}. Bylaw does not read application config or choose default checks for the caller.

Usage

Choose the checks you want to enforce and pass them with the rendered HTML string:

html = render(view)

checks = [
  Bylaw.HTML.Check.RequireLinkHref,
  Bylaw.HTML.Check.PreferButtonForAction,
  Bylaw.HTML.Check.PreferLinkForNavigation,
  Bylaw.HTML.Check.RequireImageAlt,
  Bylaw.HTML.Check.RequireButtonType,
  Bylaw.HTML.Check.RequireInputAutocomplete,
  Bylaw.HTML.Check.NoInlineStyle
]

assert :ok = Bylaw.HTML.validate_html(html, checks)

When validation fails, validate_html/2 returns every issue found by the enabled checks:

case Bylaw.HTML.validate_html(html, checks) do
  :ok -> :ok
  {:error, issues} -> flunk(inspect(issues, pretty: true))
end

Built-in checks

Built-in checks live under Bylaw.HTML.Check.*. Each check module documents its own examples, notes, options, and copyable check specs.

Notes

The validation boundary is the rendered HTML string. Checks can see the browser-facing markup, but they do not know which source component or template produced it.

Examples

iex> Bylaw.HTML.validate_html(~s(<a href="/settings">Settings</a>), [])
:ok

iex> {:error, [issue]} =
...>   Bylaw.HTML.validate_html(
...>     ~s(<button phx-click='[["navigate",{"href":"/settings","replace":false}]]'>Settings</button>),
...>     [Bylaw.HTML.Check.PreferLinkForNavigation]
...>   )
iex> issue.check
Bylaw.HTML.Check.PreferLinkForNavigation