Slide 1
Slide 1 text
Developing a Vim plugin with
Ruby, or when in Ruby do as
the Rubyists do
VimConf 2023 Tiny
OKURA Masafumi, 2023-11-18
Slide 2
Slide 2 text
English
Slide 3
Slide 3 text
20 minutes
Slide 4
Slide 4 text
Me
Slide 5
Slide 5 text
About me
• Name: OKURA Masafumi
• Company: nil (freelancer)
• Specialty: Web development with Rails
• Activities: Rubyist, Kaigi on Rails chief organizer, OSS maintainer
(Alba), meetup organizer (Grow.rb, Rubygems Code Reading Meetup)
• I brought some KoR swags today, talk to me to get one!
• Vim user history: Vim (2013-2018), Neovim (2018-)
Slide 6
Slide 6 text
VimConf and me
• -2017: Attendee
• 2018: Speaker (A day in the life of a (ordinary) Vimmer)
• 2019: Organizer
• After the conference, I was recommended to translate a book
called “Mastering Vim” and I did it. It’s “ϚελϦϯάVim”
• 2023: Speaker <- new!
Slide 7
Slide 7 text
No content
Slide 8
Slide 8 text
No content
Slide 9
Slide 9 text
Question
Slide 10
Slide 10 text
Your choice of
the language
Slide 11
Slide 11 text
…for the
development of
Vim plugins
Slide 12
Slide 12 text
/(Neo)?vim/
Slide 13
Slide 13 text
Language for the development of vim plugins
1. Vim script
2. Vim9 script
3. Lua
4. Deno
Slide 14
Slide 14 text
Language for the development of vim plugins
1. Vim script
2. Vim9 script
3. Lua
4. Deno
5. Ruby
Slide 15
Slide 15 text
No one
(I believe)
Slide 16
Slide 16 text
Why Ruby?
Slide 17
Slide 17 text
Developing a Vim plugin with
Ruby, or when in Ruby do as
the Rubyists do
VimConf 2023 Tiny
OKURA Masafumi, 2023-11-18
Slide 18
Slide 18 text
Developing a Vim plugin with
Ruby, or when in Ruby do as
the Rubyists do
VimConf 2023 Tiny
OKURA Masafumi, 2023-11-18
Slide 19
Slide 19 text
When in Ruby
Slide 20
Slide 20 text
When you want
to manipulate
Ruby code
Slide 21
Slide 21 text
Do as the
Rubyists do
Slide 22
Slide 22 text
What do
Rubyists do?
Slide 23
Slide 23 text
AST
Slide 24
Slide 24 text
Abstract
Syntax
Tree
Slide 25
Slide 25 text
RubyVM::AbstractSyntaxTree
Slide 26
Slide 26 text
RubyVM::AbstractSyntaxTree
• Stdlib
• No external dependencies
• No need to install something via package managers
• Takes Ruby source code as a String and returns AST root node
• Not best for modifying code but good enough to get some
information from code
Slide 27
Slide 27 text
RSpec
Slide 28
Slide 28 text
RSpec
• One of the most famous testing libraries for Ruby
• In fact, one of the most downloaded library
• Introducing DSLs such as `describe`, `context`, `it` and `let`
• Readable as English
• These can be deeply nested
• Tests can be implicit with `subject` and `is_expected`
Slide 29
Slide 29 text
The problem
Slide 30
Slide 30 text
What is the
current
context/subject?
Slide 31
Slide 31 text
rspec-current.vim
Slide 32
Slide 32 text
Demo
Slide 33
Slide 33 text
Why not LSP?
Slide 34
Slide 34 text
Why not LSP for this case?
• Too trivial/niche
• I cannot push this feature into generic LSP servers
• Not enough functionality on extension/add-on/plugin system
• ruby-lsp provides add-on system, but it’s immature now
• Too many things to learn for only one feature
• LSP is not the easiest thing to learn
Slide 35
Slide 35 text
Ruby as a
solution!
Slide 36
Slide 36 text
Using Ruby as a development language
• Simple/Easy
• One
fi
le to work with, no external dependencies
• Straightforward
• Just plain Ruby code
• Less things to learn
• We need to learn how to develop a plugin with Ruby, but it’s
simpler than learning LSP
Slide 37
Slide 37 text
How to
Slide 38
Slide 38 text
gem install neovim
If you use Neovim
Slide 39
Slide 39 text
rubyeval
Slide 40
Slide 40 text
Ruby heredoc
Slide 41
Slide 41 text
Summary
Slide 42
Slide 42 text
Usecase
Slide 43
Slide 43 text
Usecase for using
Ruby as a
development
language for vim
Slide 44
Slide 44 text
Language-
speci
fi
c features
Slide 45
Slide 45 text
Use your own
language!
Slide 46
Slide 46 text
Because you can
Slide 47
Slide 47 text
Because of Vim
Slide 48
Slide 48 text
Because Vim is
so kind to let
you do so
Slide 49
Slide 49 text
Happy vimming!