Sord is a Sorbet and YARD crossover. It can automatically generate RBI and RBS type signature files by looking at the types specified in YARD documentation comments.
If your project is already YARD documented, then this can generate most of the type signatures you need!
Sord is the perfect way to jump-start the adoption of types in your project, whether you plan to use Sorbet's RBI format or Ruby 3/Steep's RBS format.
Try Sord online at: sord.aaronc.cc
Sord has the following features:
- Automatically generates signatures for modules, classes and methods
- Support for multiple parameter or return types (
T.any
/|
) - Gracefully handles missing YARD types (
T.untyped
/untyped
) - Can infer setter parameter type from the corresponding getter's return type
- Recognises mixins (
include
andextend
) - Support for generic types such as
Array<T>
andHash<K, V>
- Can infer namespaced classes (
[Bar]
can becomeGemName::Foo::Bar
) - Handles return types which can be
nil
(T.nilable
/untyped
) - Handles duck types (
T.untyped
/untyped
) - Support for ordered list types (
[Array(Integer, Symbol)]
becomes[Integer, Symbol]
) - Support for boolean types (
[true, false]
becomesT::Boolean
/bool
) - Support for
&block
parameters documented with@yieldparam
and@yieldreturn
Install Sord with gem install sord
.
Sord is a command line tool. To use it, open a terminal in the root directory
of your project and invoke sord
, passing a path where you'd like to save your
file (this file will be overwritten):
sord defs.rbi
Sord will generate YARD docs and then print information about what it's inferred as it runs. It is best to fix any issues in the YARD documentation, as any edits made to the resulting file will be replaced if you re-run Sord.
The output type is inferred by the file extension you use, but you can also
specify it explicitly with --rbi
or --rbs
.
RBI files generated by Sord can be used in two main ways:
- Shipped in the gem itself.
- Contributed to sorbet-typed.
Generally, you should ship the type signatures with your gem if possible. sorbet-typed is meant to be a place for gems that are no longer updated or where the maintainer is unwilling to ship type signatures with the gem itself.
Sord also takes some flags to alter the generated file:
--rbi
/--rbs
: Override the output format inferred from the file extension.--no-sord-comments
: Generates the file without any Sord comments about warnings/inferences/errors. (The original file's comments will still be included.)--no-regenerate
: By default, Sord will regenerate a repository's YARD docs for you. This option skips regenerating the YARD docs.--break-params
: Determines how many parameters are necessary before the signature is changed from a single-line to a multi-line block. (Default: 4)--replace-errors-with-untyped
: UsesT.untyped
instead ofSORD_ERROR_*
constants.--replace-unresolved-with-untyped
: UsesT.untyped
when Sord is unable to resolve a constant.--include-messages
and--exclude-messages
: Used to filter the logging messages given by Sord.--include-messages
acts as a whitelist, printing only messages of the specified logging kinds, whereas--exclude-messages
acts as a blacklist and suppresses the specified logging kinds. Both flags take a comma-separated list of logging kinds, for exampleomit,infer
. When using--include-messages
, thedone
kind is included by default. (You cannot specify both--include-messages
and--exclude-messages
.)--exclude-untyped
: Exclude methods and attributes with untyped return values.--tags TAGS
: Provide a list of comma-separated tags as understood by theyard
command. E.g. `--tags 'mytag:My Description,mytag2:My New Description'
Say we have this file, called test.rb
:
module Example
class Person
# @param name [String] The name of the Person to create.
# @param age [Integer] The age of the Person to create.
# @return [Example::Person]
def initialize(name, age)
@name = name
@age = age
end
# @return [String]
attr_accessor :name
# @return [Integer]
attr_accessor :age
# @param possible_names [Array<String>] An array of potential names to choose from.
# @param possible_ages [Array<Integer>] An array of potential ages to choose from.
# @return [Example::Person]
def self.construct_randomly(possible_names, possible_ages)
Person.new(possible_names.sample, possible_ages.sample)
end
end
end
First, generate a YARD registry by running yardoc test.rb
. Then, we can run
sord test.rbi
to generate the RBI file. (Careful not to overwrite your code
files! Note the .rbi
file extension.) In doing this, Sord prints:
[INFER] Assuming from filename you wish to generate in RBI format
[DONE ] Processed 8 objects (2 namespaces and 6 methods)
The test.rbi
file then contains a complete RBI file for test.rb
:
# typed: strong
module Example
class Person
# _@param_ `name` — The name of the Person to create.
#
# _@param_ `age` — The age of the Person to create.
sig { params(name: String, age: Integer).void }
def initialize(name, age); end
# _@param_ `possible_names` — An array of potential names to choose from.
#
# _@param_ `possible_ages` — An array of potential ages to choose from.
sig { params(possible_names: T::Array[String], possible_ages: T::Array[Integer]).returns(Example::Person) }
def self.construct_randomly(possible_names, possible_ages); end
sig { returns(String) }
attr_accessor :name
sig { returns(Integer) }
attr_accessor :age
end
end
If we had instead generated test.rbs
, we would get this file in RBS format:
module Example
class Person
# _@param_ `name` — The name of the Person to create.
#
# _@param_ `age` — The age of the Person to create.
def initialize: (String name, Integer age) -> void
# _@param_ `possible_names` — An array of potential names to choose from.
#
# _@param_ `possible_ages` — An array of potential ages to choose from.
def self.construct_randomly: (Array[String] possible_names, Array[Integer] possible_ages) -> Example::Person
attr_accessor name: String
attr_accessor age: Integer
end
end
The general rule of thumb for type conversions is:
- If Sord understands the YARD type, then it is converted into the RBI or RBS type.
- If the YARD type is missing, Sord fills in
T.untyped
. - If the YARD type can't be understood, Sord creates an undefined Ruby constant
with a similar name to the unknown YARD type. For example, the obviously
invalid YARD type
A%B
will become a constant calledSORD_ERROR_AB
. You should search through your resulting file to find and fix andSORD_ERROR
s.
Bug reports and pull requests are welcome on GitHub at https://github.com/AaronC81/sord. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
While contributing, if you want to see the results of your changes to Sord you
can use the examples:seed
Rake task. The task uses Sord to generate types for
a number of open source Ruby gems, including Bundler, Haml, Rouge, and RSpec.
rake examples:seed
(and rake examples:reseed
to regenerate the files) will
clone the repositories of these gems into sord_examples/
and then generate the
files into the same directory.
The gem is available as open source under the terms of the MIT License.
Everyone interacting in the Sord project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.