First commit

Author: Ray Zane

.gitignore

@@ -0,0 +1,9 @@
+/.bundle/
+/.yardoc
+/Gemfile.lock
+/_yardoc/
+/coverage/
+/doc/
+/pkg/
+/spec/reports/
+/tmp/

.rspec

@@ -0,0 +1,2 @@
+--format documentation
+--color

.travis.yml

@@ -0,0 +1,4 @@
+language: ruby
+rvm:
+  - 2.1.6
+before_install: gem install bundler -v 1.11.2

Gemfile

@@ -0,0 +1,4 @@
+source 'https://rubygems.org'
+
+# Specify your gem's dependencies in baby_squeel.gemspec
+gemspec

LICENSE.txt

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2016 Ray Zane
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

README.md

@@ -0,0 +1,41 @@
+# BabySqueel
+
+Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file `lib/baby_squeel`. To experiment with that code, run `bin/console` for an interactive prompt.
+
+TODO: Delete this and the text above, and describe your gem
+
+## Installation
+
+Add this line to your application's Gemfile:
+
+```ruby
+gem 'baby_squeel'
+```
+
+And then execute:
+
+    $ bundle
+
+Or install it yourself as:
+
+    $ gem install baby_squeel
+
+## Usage
+
+TODO: Write usage instructions here
+
+## 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/[USERNAME]/baby_squeel.
+
+
+## License
+
+The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).
+

Rakefile

@@ -0,0 +1,6 @@
+require "bundler/gem_tasks"
+require "rspec/core/rake_task"
+
+RSpec::Core::RakeTask.new(:spec)
+
+task :default => :spec

baby_squeel.gemspec

@@ -0,0 +1,37 @@
+# coding: utf-8
+lib = File.expand_path('../lib', __FILE__)
+$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+require 'baby_squeel/version'
+
+Gem::Specification.new do |spec|
+  spec.name          = "baby_squeel"
+  spec.version       = BabySqueel::VERSION
+  spec.authors       = ["Ray Zane"]
+  spec.email         = ["[email protected]"]
+
+  spec.summary       = %q{TODO: Write a short summary, because Rubygems requires one.}
+  spec.description   = %q{TODO: Write a longer description or delete this line.}
+  spec.homepage      = "TODO: Put your gem's website or public repo URL here."
+  spec.license       = "MIT"
+
+  # Prevent pushing this gem to RubyGems.org by setting 'allowed_push_host', or
+  # delete this section to allow pushing this gem to any host.
+  if spec.respond_to?(:metadata)
+    spec.metadata['allowed_push_host'] = "TODO: Set to 'http://mygemserver.com'"
+  else
+    raise "RubyGems 2.0 or newer is required to protect against public gem pushes."
+  end
+
+  spec.files         = `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+  spec.bindir        = "exe"
+  spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
+  spec.require_paths = ["lib"]
+
+  spec.add_dependency 'activerecord', '>= 4.0.0'
+
+  spec.add_development_dependency "bundler", "~> 1.11"
+  spec.add_development_dependency "rake", "~> 10.0"
+  spec.add_development_dependency "rspec", "~> 3.0"
+  spec.add_development_dependency 'simplecov'
+  spec.add_development_dependency "sqlite3"
+end

bin/console

@@ -0,0 +1,14 @@
+#!/usr/bin/env ruby
+
+require "bundler/setup"
+require "baby_squeel"
+
+# You can add fixtures and/or initialization code here to make experimenting
+# with your gem easier. You can also use a different console, if you like.
+
+# (If you use this, don't forget to add pry to your Gemfile!)
+# require "pry"
+# Pry.start
+
+require "irb"
+IRB.start

bin/setup

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -euo pipefail
+IFS=$'\n\t'
+set -vx
+
+bundle install
+
+# Do any other automated setup that you need to do here

lib/baby_squeel.rb

@@ -0,0 +1,25 @@
+require 'active_record'
+require 'baby_squeel/version'
+require 'baby_squeel/dsl'
+
+module BabySqueel
+  module WhereChain
+    def has(&block)
+      @scope.where_values += DSL.evaluate(@scope, &block)
+      @scope
+    end
+  end
+
+  module QueryMethods
+    def selecting(&block)
+      select DSL.evaluate(self, &block)
+    end
+
+    def ordering(&block)
+      order DSL.evaluate(self, &block)
+    end
+  end
+end
+
+ActiveRecord::Base.extend BabySqueel::QueryMethods
+ActiveRecord::QueryMethods::WhereChain.prepend BabySqueel::WhereChain

lib/baby_squeel/dsl.rb

@@ -0,0 +1,48 @@
+module BabySqueel
+  class DSL
+    def self.evaluate(scope, &block)
+      new(scope).evaluate(&block)
+    end
+
+    def initialize(scope)
+      @scope = scope
+    end
+
+    def [](key)
+      @scope.arel_table[key]
+    end
+
+    def func(name, *args)
+      Arel::Nodes::NamedFunction.new(name.to_s, args)
+    end
+
+    def evaluate(&block)
+      if block.arity.zero?
+        [instance_eval(&block)]
+      else
+        [block.call(self)]
+      end
+    end
+
+    private
+
+    def respond_to_missing?(name, *)
+      @scope.column_names.include?(name.to_s) ||
+        !@scope.reflect_on_association(name).nil?
+    end
+
+    def method_missing(name, *args, &block)
+      if args.empty? && !block_given?
+        if @scope.column_names.include?(name.to_s)
+          @scope.arel_table[name]
+        elsif assoc = @scope.reflect_on_association(name)
+          assoc.klass.arel_table
+        else
+          super
+        end
+      else
+        super
+      end
+    end
+  end
+end

lib/baby_squeel/version.rb

@@ -0,0 +1,3 @@
+module BabySqueel
+  VERSION = "0.1.0"
+end

spec/baby_squeel/dsl_spec.rb

@@ -0,0 +1,82 @@
+require 'spec_helper'
+require 'baby_squeel/dsl'
+
+describe BabySqueel::DSL do
+  subject(:dsl) { BabySqueel::DSL.new(Post) }
+
+  describe '#respond_to?' do
+    it 'resolves attributes' do
+      expect(dsl.respond_to?(:id)).to eq(true)
+    end
+
+    it 'resolves associations' do
+      expect(dsl.respond_to?(:author)).to eq(true)
+    end
+  end
+
+  describe '#method_missing' do
+    it 'resolves attributes' do
+      expect(dsl.id).to be_an(Arel::Attribute)
+    end
+
+    it 'resolves associations' do
+      expect(dsl.author).to eq(Author.arel_table)
+    end
+
+    it 'does not resolve when arguments are given' do
+      expect { dsl.id(:arg) }.to raise_error(NameError)
+    end
+
+    it 'does not resolve when a block is given' do
+      expect { dsl.id { 'block' } }.to raise_error(NameError)
+    end
+
+    it 'does not resolve for non-existent columns' do
+      expect { dsl.non_existent_column }.to raise_error(NameError)
+    end
+  end
+
+  describe '#evaluate' do
+    context 'when an arity is given' do
+      it 'yields itself' do
+        dsl.evaluate do |table|
+          expect(table).to be_a(BabySqueel::DSL)
+        end
+      end
+
+      it 'does not change self' do
+        this = self
+        that = nil
+        dsl.evaluate { |t| that = self }
+        expect(that).to equal(this)
+      end
+    end
+
+    context 'when no arity is given' do
+      it 'changes self' do
+        this = self
+        that = nil
+        dsl.evaluate { that = self }
+        expect(that).not_to equal(this)
+      end
+
+      it 'resolves attributes without a receiver' do
+        resolution = nil
+        dsl.evaluate { resolution = title }
+        expect(resolution).to eq(Post.arel_table[:title])
+      end
+    end
+  end
+
+  describe '#[]' do
+    it 'returns an arel attribute' do
+      expect(dsl[:title]).to be_an(Arel::Attribute)
+    end
+  end
+
+  describe '#func' do
+    it 'constructs a named function' do
+      expect(dsl.func(:coalesce, 0, 1).to_sql).to eq('coalesce(0, 1)')
+    end
+  end
+end

spec/baby_squeel/query_methods_spec.rb

@@ -0,0 +1,67 @@
+require 'spec_helper'
+
+describe BabySqueel::QueryMethods do
+  describe '#selecting' do
+    it 'selects using arel' do
+      relation = Post.selecting { [id, title] }
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT "posts"."id", "posts"."title"
+        FROM "posts"
+      EOSQL
+    end
+
+    it 'selects aggregates' do
+      relation = Post.selecting { id.count }
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT COUNT("posts"."id")
+        FROM "posts"
+      EOSQL
+    end
+
+    it 'selects associations' do
+      relation = Post.joins(:author).selecting {
+        [id, author[:id]]
+      }
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT "posts"."id", "authors"."id"
+        FROM "posts"
+        INNER JOIN "authors" ON "authors"."id" = "posts"."author_id"
+      EOSQL
+    end
+  end
+
+  describe '#ordering' do
+    it 'orders using arel' do
+      relation = Post.ordering { title.desc }
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT "posts".* FROM "posts"
+        ORDER BY "posts"."title" DESC
+      EOSQL
+    end
+
+    it 'orders using multiple arel columns' do
+      relation = Post.ordering {
+        [title.desc, published_at.asc]
+      }
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT "posts".* FROM "posts"
+        ORDER BY "posts"."title" DESC, "posts"."published_at" ASC
+      EOSQL
+    end
+
+    it 'orders on an aggregate column' do
+      relation = Post.ordering { id.count }.group(:id)
+
+      expect(relation.to_sql.squish).to eq(<<-EOSQL.squish)
+        SELECT "posts".* FROM "posts"
+        GROUP BY "posts"."id"
+        ORDER BY COUNT("posts"."id")
+      EOSQL
+    end
+  end
+end