Ruby function declared with var_kwargs => true not called properly within @if directive

[Grégory Pakosz]

Hello,

Assuming the following Ruby function exposed to Sass:

def foo(string, params)
  assert_type string, :String
  assert_type params, :Hash

  result = ... // real business logic irrelevant to the bug report

  case result
  when TrueClass, FalseClass
    bool(result)
  when Array
    list(result, :comma)
  when Hash
    map(result)
  when nil
    null
  when Numeric
    number(result)
  else
    params['unquote'] ? unquoted_string(result) : quoted_string(result)
  end
end
declare :foo, [:string], var_kwargs: true

When calling this function within an @if directive:

@if foo('...') {
  ...
}

Sass reports a syntax error:

Sass::SyntaxError: wrong number of arguments (1 for 2) for `foo'

Despite the documentation stating:

Whether the function accepts other keyword arguments in addition to those in :args. If this is true, the Ruby function will be passed a hash from strings to Values as the last argument. In addition, if this is true and :var_args is not, Sass will ensure that the last argument passed is a hash.

Declaring the Ruby function with params = {} mitigates the problem:

def foo(string, params = {})
  ...
end
declare :foo, [:string], var_kwargs: true

[Grégory Pakosz]

Forgot to verify versions, it seems the bug happens at least in 3.4.25 but not in 3.6.0. I can't pinpoint what solves it though

[Natalie Weizenbaum]

If this is working in 3.6.0, then the bug is already fixed.