Module: T::Private::Methods

Defined in:
lib/types/private/methods/_methods.rb,
lib/types/private/methods/decl_builder.rb

Overview

typed: true

Defined Under Namespace

Modules: ARG_NOT_PROVIDED, CallValidation, MethodHooks, Modes, PROC_TYPE, SignatureValidation, SingletonMethodHooks Classes: DeclBuilder, Declaration, DeclarationBlock, Signature

Constant Summary collapse

TOP_SELF =

This has to be here, and can’t be nested inside ‘T::Private::Methods`, because the value of `self` depends on lexical (nesting) scope, and we specifically need a reference to the file-level self, i.e. `main:Object`

self

Class Method Summary collapse

Class Method Details

._check_final_ancestors(target, source_method_names, source) ⇒ Object

when target includes a module with instance methods source_method_names, ensure there is zero intersection between the final instance methods of target and source_method_names. so, for every m in source_method_names, check if there is already a method defined on one of target_ancestors with the same name that is final.

we assume that source_method_names has already been filtered to only include method names that were declared final at one point.



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# File 'lib/types/private/methods/_methods.rb', line 114

def self._check_final_ancestors(target, source_method_names, source)
  source_ancestors = nil
  if T::Private::IS_TYPECHECKING
    # Need to avoid a pinning error, but don't want to use runtime types in _methods.rb
    source_ancestors = T.let(nil, T.nilable(T::Array[T::Module[T.anything]]))
  end
  # use reverse_each to check farther-up ancestors first, for better error messages.
  target.ancestors.reverse_each do |ancestor|
    final_methods = @modules_with_final.fetch(ancestor, nil)
    # In this case, either ancestor didn't have any final methods anywhere in its
    # ancestor chain, or ancestor did have final methods somewhere in its ancestor
    # chain, but no final methods defined in ancestor itself.  Either way, there
    # are no final methods to check here, so we can move on to the next ancestor.
    next unless final_methods
    source_method_names.each do |method_name|
      next unless final_methods.include?(method_name)

      # If we get here, we are defining a method that some ancestor declared as
      # final.  however, we permit a final method to be defined multiple
      # times if it is the same final method being defined each time.
      if source
        if !source_ancestors
          source_ancestors = source.ancestors
          # filter out things without actual final methods just to make sure that
          # the below checks (which should be uncommon) go as quickly as possible.
          source_ancestors.select! do |a|
            @modules_with_final.fetch(a, nil)
          end
        end
        # final-ness means that there should be no more than one index for which
        # the below block returns true.
        defining_ancestor_idx = source_ancestors.index do |a|
          @modules_with_final.fetch(a).include?(method_name)
        end
        next if defining_ancestor_idx && source_ancestors[defining_ancestor_idx] == ancestor
      end

      final_sig = T::Private::Methods.signature_for_method(ancestor.instance_method(method_name))
      definition_file, definition_line = final_sig&.method&.source_location
      is_redefined = target == ancestor
      caller_loc = T::Private::CallerUtils.find_caller { |loc| !loc.path.to_s.start_with?(SORBET_RUNTIME_LIB_PATH) }
      extra_info = "\n"
      if caller_loc
        extra_info = (is_redefined ? "Redefined" : "Overridden") + " here: #{caller_loc.path}:#{caller_loc.lineno}\n"
      end

      error_message = "The method `#{method_name}` on #{ancestor} was declared as final and cannot be " +
                      (is_redefined ? "redefined" : "overridden in #{target}")
      pretty_message = "#{error_message}\n" \
                       "Made final here: #{definition_file}:#{definition_line}\n" \
                       "#{extra_info}"

      begin
        raise pretty_message
      rescue => e
        # sig_validation_error_handler raises by default; on the off chance that
        # it doesn't raise, we need to ensure that the rest of signature building
        # sees a consistent state.  This sig failed to validate, so we should get
        # rid of it.  If we don't do this, errors of the form "You called sig
        # twice without declaring a method in between" will non-deterministically
        # crop up in tests.
        T::Private::DeclState.current.reset!
        T::Configuration.sig_validation_error_handler(e, {})
      end
    end
  end
end

._handle_missing_method_signature(receiver, original_method, callee) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 270

def self._handle_missing_method_signature(receiver, original_method, callee)
  method_sig = T::Private::Methods.signature_for_method(original_method)
  if !method_sig
    raise "`sig` not present for method `#{callee}` on #{receiver.inspect} but you're trying to run it anyways. " \
      "This should only be executed if you used `alias_method` to grab a handle to a method after `sig`ing it, but that clearly isn't what you are doing. " \
      "Maybe look to see if an exception was thrown in your `sig` lambda or somehow else your `sig` wasn't actually applied to the method."
  end

  if receiver.class <= original_method.owner
    receiving_class = receiver.class
  elsif receiver.singleton_class <= original_method.owner
    receiving_class = receiver.singleton_class
  elsif receiver.is_a?(Module) && receiver <= original_method.owner
    receiving_class = receiver
  else
    raise "#{receiver} is not related to #{original_method} - how did we get here?"
  end

  # Check for a case where `alias` or `alias_method` was called for a
  # method which had already had a `sig` applied. In that case, we want
  # to avoid hitting this slow path again, by moving to a faster validator
  # just like we did or will for the original method.
  #
  # If this isn't an `alias` or `alias_method` case, we're probably in the
  # middle of some metaprogramming using a Method object, e.g. a pattern like
  # `arr.map(&method(:foo))`. There's nothing really we can do to optimize
  # that here.
  receiving_method = receiving_class.instance_method(callee)
  if receiving_method != original_method && receiving_method.original_name == original_method.name
    aliasing_mod = receiving_method.owner
    method_sig = method_sig.as_alias(callee)
    unwrap_method(aliasing_mod, method_sig, original_method)
  end

  method_sig
end

._hook_impl(target, source) ⇒ Object

the module target is adding the methods from the module source to itself. we need to check that for all instance methods M on source, M is not defined on any of target’s ancestors.



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# File 'lib/types/private/methods/_methods.rb', line 494

def self._hook_impl(target, source)
  # we do not need to call add_was_ever_final here, because we have already marked
  # any such methods when source was originally defined.
  if !@modules_with_final.include?(target)
    if !@modules_with_final.include?(source)
      return
    end
    # Side-effectfully initialize the value if it's not already there
    @modules_with_final[target]
    install_hooks(target)
    return
  end

  methods = source.instance_methods
  methods.select! do |method_name|
    @was_ever_final_names.include?(method_name)
  end
  if methods.empty?
    return
  end

  _check_final_ancestors(target, methods, source)
end

._on_method_added(hook_mod, mod, method_name) ⇒ Object

Only public because it needs to get called below inside the replace_method blocks below.



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# File 'lib/types/private/methods/_methods.rb', line 196

def self._on_method_added(hook_mod, mod, method_name)
  if T::Private::DeclState.current.skip_on_method_added
    return
  end

  current_declaration = T::Private::DeclState.current.active_declaration

  if T::Private::Final.final_module?(mod) && (current_declaration.nil? || !current_declaration.final)
    raise "#{mod} was declared as final but its method `#{method_name}` was not declared as final"
  end
  # Don't compute mod.ancestors if we don't need to bother checking final-ness.
  if @was_ever_final_names.include?(method_name) && @modules_with_final.include?(mod)
    _check_final_ancestors(mod, [method_name], nil)
    # We need to fetch the active declaration again, as _check_final_ancestors
    # may have reset it (see the comment in that method for details).
    current_declaration = T::Private::DeclState.current.active_declaration
  end

  if current_declaration.nil?
    return
  end
  T::Private::DeclState.current.reset!

  if method_name == :method_added || method_name == :singleton_method_added
    raise(
      "Putting a `sig` on `#{method_name}` is not supported" \
      " (sorbet-runtime uses this method internally to perform `sig` validation logic)"
    )
  end

  original_method = mod.instance_method(method_name)
  sig_block = lambda do
    T::Private::Methods.run_sig(hook_mod, method_name, original_method, current_declaration)
  end

  # Always replace the original method with this wrapper,
  # which is called only on the *first* invocation.
  # This wrapper is very slow, so it will subsequently re-wrap with a much faster wrapper
  # (or unwrap back to the original method).
  key = method_owner_and_name_to_key(mod, method_name)
  unless current_declaration.raw
    T::Private::ClassUtils.replace_method(original_method, mod, method_name) do |*args, &blk|
      method_sig = T::Private::Methods.maybe_run_sig_block_for_key(key)
      method_sig ||= T::Private::Methods._handle_missing_method_signature(
        self,
        original_method,
        __callee__ || raise("Unknown __callee__ for method without a signature"),
      )

      # Should be the same logic as CallValidation.wrap_method_if_needed but we
      # don't want that extra layer of indirection in the callstack
      if method_sig.mode == T::Private::Methods::Modes.abstract
        # We're in an interface method, keep going up the chain
        if defined?(super)
          super(*args, &blk)
        else
          raise NotImplementedError.new("The method `#{method_sig.method_name}` on #{mod} is declared as `abstract`. It does not have an implementation.")
        end
      # Note, this logic is duplicated (intentionally, for micro-perf) at `CallValidation.wrap_method_if_needed`,
      # make sure to keep changes in sync.
      elsif method_sig.check_level == :always || (method_sig.check_level == :tests && T::Private::RuntimeLevels.check_tests?)
        CallValidation.validate_call(self, original_method, method_sig, args, blk)
      else
        original_method.bind_call(self, *args, &blk)
      end
    end
  end

  @sig_wrappers[key] = sig_block
  if current_declaration.final
    add_module_with_final_method(mod, method_name)
  end
end

.add_module_with_final_method(mod, method_name) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 182

def self.add_module_with_final_method(mod, method_name)
  @was_ever_final_names[method_name] = true

  # Side-effectfully initializes the value if it's not already there
  methods = @modules_with_final[mod]
  if methods.nil?
    methods = {}
    @modules_with_final[mod] = methods
  end
  methods[method_name] = true
  nil
end

.all_checked_tests_sigs ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 488

def self.all_checked_tests_sigs
  @signatures_by_method.values.select { |sig| sig.check_level == :tests }
end

.build_sig(hook_mod, method_name, original_method, current_declaration) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 353

def self.build_sig(hook_mod, method_name, original_method, current_declaration)
  begin
    # We allow `sig` in the current module's context (normal case) and
    if hook_mod != current_declaration.mod &&
       # inside `class << self`, and
       hook_mod.singleton_class != current_declaration.mod &&
       # on `self` at the top level of a file
       current_declaration.mod != TOP_SELF
      raise "A method (#{method_name}) is being added on a different class/module (#{hook_mod}) than the " \
            "last call to `sig` (#{current_declaration.mod}). Make sure each call " \
            "to `sig` is immediately followed by a method definition on the same " \
            "class/module."
    end

    signature = Signature.new(
      method: original_method,
      method_name: method_name,
      raw_arg_types: current_declaration.params,
      raw_return_type: current_declaration.returns,
      bind: current_declaration.bind,
      mode: current_declaration.mode,
      check_level: current_declaration.checked,
      on_failure: current_declaration.on_failure,
      override_allow_incompatible: current_declaration.override_allow_incompatible,
      defined_raw: current_declaration.raw,
    )

    SignatureValidation.validate(signature)
    signature
  rescue => e
    super_method = original_method.super_method
    super_signature = signature_for_method(super_method) if super_method

    T::Configuration.sig_validation_error_handler(
      e,
      method: original_method,
      declaration: current_declaration,
      signature: signature,
      super_signature: super_signature
    )

    Signature.new_untyped(method: original_method)
  end
end

.declare_sig(mod, loc, arg, &blk) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 53

def self.declare_sig(mod, loc, arg, &blk)
  T::Private::DeclState.current.active_declaration = _declare_sig_internal(mod, loc, arg, &blk)

  nil
end

.finalize_proc(decl) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 78

def self.finalize_proc(decl)
  decl.finalized = true

  if decl.mode != Modes.standard
    raise "Procs cannot have override/abstract modifiers"
  end
  if decl.mod != PROC_TYPE
    raise "You are passing a DeclBuilder as a type. Did you accidentally use `self` inside a `sig` block? Perhaps you wanted the `T.self_type` instead: https://sorbet.org/docs/self-type"
  end
  if decl.returns == ARG_NOT_PROVIDED
    raise "Procs must specify a return type"
  end
  if decl.on_failure != ARG_NOT_PROVIDED
    raise "Procs cannot use .on_failure"
  end

  if decl.params == ARG_NOT_PROVIDED
    decl.params = {}
  end

  T::Types::Proc.new(decl.params, decl.returns)
end

.has_sig_block_for_method(method) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 416

def self.has_sig_block_for_method(method)
  has_sig_block_for_key(method_to_key(method))
end

.install_hooks(mod) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 570

def self.install_hooks(mod)
  return if @installed_hooks.include?(mod)
  @installed_hooks[mod] = true

  if mod == TOP_SELF
    # self at the top-level of a file is weirdly special in Ruby
    # The Ruby VM on startup creates an `Object.new` and stashes it.
    # Unlike when we're using sig inside a module, `self` is actually a
    # normal object, not an instance of Module.
    #
    # Thus we can't ask things like mod.singleton_class? (since that's
    # defined only on Module, not on Object) and even if we could, the places
    # where we need to install the hooks are special.
    mod.extend(SingletonMethodHooks) # def self.foo; end (at top level)
    Object.extend(MethodHooks)       # def foo; end      (at top level)
    return
  end

  # See https://github.com/sorbet/sorbet/pull/3964 for an explanation of why this
  # check (which theoretically should not be needed) is actually needed.
  if !mod.is_a?(Module)
    return
  end

  if mod.singleton_class?
    mod.include(SingletonMethodHooks)
  else
    mod.extend(MethodHooks)
  end
  mod.extend(SingletonMethodHooks)
end

.maybe_run_sig_block_for_key(key) ⇒ Object

Only public so that it can be accessed in the closure for _on_method_added



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# File 'lib/types/private/methods/_methods.rb', line 429

def self.maybe_run_sig_block_for_key(key)
  run_sig_block_for_key(key) if has_sig_block_for_key(key)
end

.maybe_run_sig_block_for_method(method) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 424

def self.maybe_run_sig_block_for_method(method)
  maybe_run_sig_block_for_key(method_to_key(method))
end

.run_all_sig_blocks(force_type_init: true) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 479

def self.run_all_sig_blocks(force_type_init: true)
  loop do
    first_wrapper = @sig_wrappers.first
    break unless first_wrapper
    key, = first_wrapper
    run_sig_block_for_key(key, force_type_init: force_type_init)
  end
end

.run_builder(declaration_block) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 339

def self.run_builder(declaration_block)
  blk_or_decl = declaration_block.blk_or_decl
  return blk_or_decl if blk_or_decl.is_a?(Declaration)
  if blk_or_decl.nil?
    raise "DeclarationBlock for #{declaration_block.mod} at #{declaration_block.loc} should have already been unwrapped"
  end

  builder = DeclBuilder.new(declaration_block.mod, declaration_block.raw)
  decl = builder.instance_exec(&blk_or_decl).finalize!.decl
  # Record that we've already run `blk` once and constructed a `Declaration`
  declaration_block.blk_or_decl = decl
  decl
end

.run_sig(hook_mod, method_name, original_method, declaration_block) ⇒ Object

Executes the ‘sig` block, and converts the resulting Declaration to a Signature.



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# File 'lib/types/private/methods/_methods.rb', line 309

def self.run_sig(hook_mod, method_name, original_method, declaration_block)
  current_declaration =
    begin
      run_builder(declaration_block)
    rescue DeclBuilder::BuilderError => e
      T::Configuration.sig_builder_error_handler(e, declaration_block.loc)
      nil
    end

  # Release location information sooner
  declaration_block.loc = nil

  signature =
    if current_declaration
      build_sig(hook_mod, method_name, original_method, current_declaration)
    else
      Signature.new_untyped(method: original_method)
    end

  unwrap_method(signature.method.owner, signature, original_method)

  # Drop this declaration. Only drop it after we've actually wrapped the
  # method and recorded the signature, because that might raise an exception,
  # leaving the declaration in a weird state if the program rescues that
  # exception and continues.
  declaration_block.blk_or_decl = nil

  signature
end

.run_sig_block_for_method(method) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 433

def self.run_sig_block_for_method(method)
  run_sig_block_for_key(method_to_key(method))
end

.set_final_checks_on_hooks(enable) ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 518

def self.set_final_checks_on_hooks(enable)
  is_enabled = !@old_hooks.nil?
  if enable == is_enabled
    return
  end
  if is_enabled
    # A cut-down version of T::Private::ClassUtils::ReplacedMethod#restore, because we
    # should only be resetting final hooks during tests.
    T::Configuration.without_ruby_warnings do
      Module.define_method(:included, @old_hooks[0])
      Module.define_method(:extended, @old_hooks[1])
      Class.define_method(:inherited, @old_hooks[2])
    end
    @old_hooks = nil
  else
    # Grab the original methods before replacing them, so that each block
    # closure can reference a variable that is already assigned.
    # (Do this directly, to avoid pinning errors)
    old_included = Module.instance_method(:included)
    T::Private::ClassUtils.replace_method(old_included, Module, :included) do |arg|
      old_included.bind_call(self, arg)
      ::T::Private::Methods._hook_impl(arg, self)
    end
    old_extended = Module.instance_method(:extended)
    T::Private::ClassUtils.replace_method(old_extended, Module, :extended) do |arg|
      old_extended.bind_call(self, arg)
      ::T::Private::Methods._hook_impl(arg.singleton_class, self)
    end
    old_inherited = Class.instance_method(:inherited)
    T::Private::ClassUtils.replace_method(old_inherited, Class, :inherited) do |arg|
      old_inherited.bind_call(self, arg)
      ::T::Private::Methods._hook_impl(arg, self)
      ::T::Private::Methods._hook_impl(arg.singleton_class, self.singleton_class)
    end
    @old_hooks = [old_included, old_extended, old_inherited]
  end
end

.signature_for_method(method) ⇒ T::Private::Methods::Signature

Returns the signature for a method whose definition was preceded by ‘sig`.

Parameters:

  • method (UnboundMethod)

Returns:



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# File 'lib/types/private/methods/_methods.rb', line 402

def self.signature_for_method(method)
  signature_for_key(method_to_key(method))
end

.start_proc ⇒ Object 



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# File 'lib/types/private/methods/_methods.rb', line 74

def self.start_proc
  DeclBuilder.new(PROC_TYPE, false)
end