# This is executable Markdown that's tested on CI.
# How is that possible? See https://gist.github.com/bwoods/1c25cb7723a06a076c2152a2781d4d49
set -o errexit -o nounset -o xtrace
alias ~~~=":<<'~~~sh'";:<<'~~~sh'

This repo includes:

• 🧱 Latest version of Bazel and dependencies
• 📦 Curated bazelrc flags via [bazelrc-preset.bzl]
• 🧰 Developer environment setup with [bazel_env.bzl]
• 🎨 rubocop and standard, using rules_lint
• ✅ Pre-commit hooks for automatic linting and formatting

First, setup the developer environment by running direnv allow and follow any prompts. This ensures that tools we call in the following steps will be on the PATH.

direnv allow .

Write a simple Ruby application:

mkdir app
>app/hello.rb cat <<'EOF'
require "faker"
puts "Hello, #{Faker::Name.name} from Bazel + Ruby!"
EOF

Declare the dependency to the package manager:

echo 'gem "faker"' >> Gemfile
bundle config set path 'vendor/bundle'
bundle install

There isn't a Gazelle extension yet, so write a BUILD file by hand:

>app/BUILD cat <<EOF
load("@rules_ruby//ruby:defs.bzl", "rb_binary")

rb_binary(
    name = "hello",
    srcs = ["hello.rb"],
    main = "hello.rb",
    deps = ["@bundle"],
)
EOF

Run it to see the result:

(Note that Bundle will spam the stdout with install information, so we just want the last line)

output=$(bazel run //app:hello | tail -1)

Let's verify the application output matches expectation:

echo "${output}" | grep -qE "^Hello, .+ from Bazel \\+ Ruby!$" || {
    echo >&2 "Wanted output matching 'Hello, <name> from Bazel + Ruby!' but got '${output}'"
    exit 1
}