class RubyLsp::Requests::SignatureHelp

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

def adjust_for_nested_target(target, parent, position)

: (Prism::Node? target, Prism::Node? parent, Hash[Symbol, untyped] position) -> Prism::Node?
In that case, we want to provide signature help for `foo` and not `another_method_call`.

foo(another_method_call)

select the right target in a situation like this:
Adjust the target of signature help in the case where we have nested method calls. This is necessary so that we 
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, global_state, position, context, dispatcher, sorbet_level) # rubocop:disable Metrics/ParameterLists

rubocop:disable Metrics/ParameterLists
: ((RubyDocument | ERBDocument) document, GlobalState global_state, Hash[Symbol, untyped] position, Hash[Symbol, untyped]? context, Prism::Dispatcher dispatcher, SorbetLevel sorbet_level) -> void 
def initialize(document, global_state, position, context, dispatcher, sorbet_level) # rubocop:disable Metrics/ParameterLists
  super()
  char_position, _ = document.find_index_by_position(position)
  delegate_request_if_needed!(global_state, document, char_position)
  node_context = RubyDocument.locate(
    document.ast,
    char_position,
    node_types: [Prism::CallNode],
    code_units_cache: document.code_units_cache,
  )
  target = adjust_for_nested_target(node_context.node, node_context.parent, position)
  @target = target #: Prism::Node?
  @dispatcher = dispatcher
  @response_builder = ResponseBuilders::SignatureHelp.new #: ResponseBuilders::SignatureHelp
  Listeners::SignatureHelp.new(@response_builder, global_state, node_context, dispatcher, sorbet_level)
end

def node_covers?(node, position)

: (Prism::Node node, Hash[Symbol, untyped] position) -> bool 
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

: -> Interface::SignatureHelp?
@override 
def perform
  return unless @target
  @dispatcher.dispatch_once(@target)
  @response_builder.response
end

def provider

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