class RubyLsp::Requests::SignatureHelp

“‘
end
bar( # -> Signature help will show the parameters of `bar`
def baz
end
def bar(a, b, c)
class Foo
“`ruby
# Example
Currently only supports methods invoked directly on `self` without taking inheritance into account.
information about the parameters of a method as you type an invocation.
request](microsoft.github.io/language-server-protocol/specification#textDocument_signatureHelp) displays
The [signature help
![Signature help demo](../../signature_help.gif)

def adjust_for_nested_target(target, parent, position) 

def adjust_for_nested_target(target, parent, position)
  # If the parent node is not a method call, then make no adjustments
  return target unless parent.is_a?(Prism::CallNode)
  # If the parent is a method call, but the target isn't, then return the parent
  return parent unless target.is_a?(Prism::CallNode)
  # If both are method calls, we check the arguments of the inner method call. If there are no arguments, then
  # we're providing signature help for the outer method call.
  #
  # If there are arguments, then we check if the arguments node covers the requested position. If it doesn't
  # cover, then we're providing signature help for the outer method call.
  arguments = target.arguments
  arguments.nil? || !node_covers?(arguments, position) ? parent : target
end

def initialize(document, index, position, context, dispatcher) 

def initialize(document, index, position, context, dispatcher)
  super()
  target, parent, nesting = document.locate_node(
    { line: position[:line], character: position[:character] },
    node_types: [Prism::CallNode],
  )
  target = adjust_for_nested_target(target, parent, position)
  @target = T.let(target, T.nilable(Prism::Node))
  @dispatcher = dispatcher
  @response_builder = T.let(ResponseBuilders::SignatureHelp.new, ResponseBuilders::SignatureHelp)
  Listeners::SignatureHelp.new(@response_builder, nesting, index, dispatcher)
end

def node_covers?(node, position) 

def node_covers?(node, position)
  location = node.location
  start_line = location.start_line - 1
  start_character = location.start_column
  end_line = location.end_line - 1
  end_character = location.end_column
  start_covered = start_line < position[:line] ||
    (start_line == position[:line] && start_character <= position[:character])
  end_covered = end_line > position[:line] ||
    (end_line == position[:line] && end_character >= position[:character])
  start_covered && end_covered
end

def perform 

def perform
  return unless @target
  @dispatcher.dispatch_once(@target)
  @response_builder.response
end

def provider 

def provider
  # Identifier characters are automatically included, such as A-Z, a-z, 0-9, _, * or :
  Interface::SignatureHelpOptions.new(
    trigger_characters: ["(", " ", ","],
  )
end