https://github.com/johansenja/lap
Generate ruby code from rbs type definitions
https://github.com/johansenja/lap
rbs ruby ruby3 type-definitions type-safety
Last synced: 3 months ago
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Generate ruby code from rbs type definitions
- Host: GitHub
- URL: https://github.com/johansenja/lap
- Owner: johansenja
- License: mit
- Created: 2020-11-29T01:41:47.000Z (over 4 years ago)
- Default Branch: master
- Last Pushed: 2020-12-04T18:05:29.000Z (over 4 years ago)
- Last Synced: 2025-02-10T13:47:38.032Z (3 months ago)
- Topics: rbs, ruby, ruby3, type-definitions, type-safety
- Language: Ruby
- Homepage:
- Size: 67.4 KB
- Stars: 1
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE.txt
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README
# Lap
Don't write your code, *and* rbs types! Write the rbs types first, then generate a template to
fill in with business logic.
A `lap`idary (or `lap`idist) is someone who cuts, polishes, or engraves precious stones.
## Usage
```sh
$ lap sig/file.rbs # outputs to stdout
$ lap sig/file.rbs > lib/file.rb # output into a file
```
## Example
0. Plan your project/module/class by writing some blueprints:
```ruby
# sig/lib/bank/account.rbs
module Bank
class Account
attr_reader interest_rate: Float
attr_reader owner: Bank::Customer
attr_reader balance: Float
def initialize: (Bank::Customer owner, Float interest_rate, ?Float balance) -> void
type date_or_dt = Date | DateTime
# can optionally specify when the transaction should take place
def deposit: (Float amount, ?when: date_or_dt) -> Float
# can optionally specify when the transaction should take place
def withdraw: (Float amount, ?when: date_or_dt) -> Float
# must filter results by specifying `to` and `from` params
def transactions: (from: date_or_dt, to: date_or_dt) -> Array[Bank::Transaction]
end
end
```
1. Generate your ruby templates
```sh
$ lap sig/lib/bank/account.rbs > lib/bank/account.rb
```
(Generates lib/bank/account.rb)
```ruby
module Bank
class Account
attr_reader :interest_rate
attr_reader :owner
attr_reader :balance
def initialize(owner, interest_rate, balance = nil)
# returns void
end
# can optionally specify when the transaction should take place
def deposit(amount, when: nil)
# TODO: return Float
end
# can optionally specify when the transaction should take place
def withdraw(amount, when: nil)
# TODO: return Float
end
# must filter results by specifying `to` and `from` params
def transactions(to:, from:)
# TODO: return Array
end
end
end
```
2. Fill in your business logic!
```ruby
module Bank
class Account
attr_reader :interest_rate
attr_reader :owner
attr_reader :balance
def initialize(owner, interest_rate, balance = 0)
@owner = owner
@interest_rate = interest_rate
@balance = balance
end
# can optionally specify when the transaction should take place
def deposit(amount, when: nil)
@balance += amount
end
# can optionally specify when the transaction should take place
def withdraw(amount, when: nil)
@balance -= amount
end
# must filter results by specifying `to` and `from` params
def transactions(to:, from:)
Transaction.where("created_at BETWEEN ? AND ?", from, to)
end
end
end
```
From here, you now have some ruby code which you can [type check](https://github.com/soutaro/steep)!
### Experimental:
There is an experimental feature which allows you to specify some ruby logic *within* your rbs files
for your methods. You specify it between `@!begin` and `@!end`, eg.:
```ruby
# take some moeny out of the customers account
# @!begin
# @balance -= amount
# @!end
def withdraw(Float amount) -> Float
```
This would produce:
```ruby
# take some moeny out of the customers account
def withdraw(amount)
@balance -= amount
end
```
## Installation
Add this line to your application's Gemfile:
```ruby
gem 'lap'
```
And then execute:
$ bundle install
Or install it yourself as:
$ gem install lap
## Configuration
You can specify preferences in a `.lap.yml` file in your project directory. Example
```yml
indent: 4 # default is 2
frozen_string_literals: false # add 'frozen_string_literal: true' to top of file; default is true
# preferred line length in characters; default is 100. Note "preferred" - not always a guarantee
preferred_line_length: 80
```
## Coverage
Currently not every feature of RBS is supported - yet! (contributions
welcome!)
Feature|Coverage
---|---
classes (includes nested)|✅
modules (includes nested)|✅
class methods|✅
instance methods|✅
required positional arguments|✅
optional positional arguments|✅
required keyword arguments|✅
optional keyword arguments|✅
method comments|✅
access modifiers|✅
attr_reader|✅
attr_writer|✅
attr_accessor|✅
include|✅
extend|✅
methods with blocks|✅
method overloading|⚠️
procs|⚠️
constants|⚠️
interfaces|⚠️
## Development
After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake spec` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release`, which will create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).
## Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/johansenja/lap.
## License
The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).