rails--rails/spec/arel/table_spec.rb

require 'spec_helper'

module Arel
  describe Table do
    before do
      @relation = Table.new(:users)
    end

    describe 'alias' do
      it 'should create a node that proxies to a table' do
        check @relation.aliases.should == []

        node = @relation.alias
        check @relation.aliases.should == [node]
        check node.name.should == 'users_2'
        check node[:id].relation.should == node
        check node[:id].relation.should != node
      end
    end

    describe 'new' do
      it 'should accept an engine' do
        rel = Table.new :users, 'foo'
        check rel.engine.should == 'foo'
      end

      it 'should accept a hash' do
        rel = Table.new :users, :engine => 'foo'
        check rel.engine.should == 'foo'
      end
    end

    describe 'take' do
      it "should add a limit" do
        manager = @relation.take 1
        manager.project SqlLiteral.new '*'
        manager.to_sql.should be_like %{ SELECT * FROM "users" LIMIT 1 }
      end
    end

    describe 'project' do
      it 'can project' do
        manager = @relation.project SqlLiteral.new '*'
        manager.to_sql.should be_like %{
          SELECT *
          FROM "users"
        }
      end
    end

    describe 'where' do
      it "returns a tree manager" do
        manager = @relation.where @relation[:id].eq 1
        manager.project @relation[:id]
        manager.should be_kind_of TreeManager
        manager.to_sql.should be_like %{
          SELECT "users"."id"
          FROM "users"
          WHERE "users"."id" = 1
        }
      end
    end

    describe 'columns' do
      it 'returns a list of columns' do
        columns = @relation.columns
        check columns.length.should == 2
        columns.map { |x| x.name }.sort.should == %w{ name id }.sort
      end
    end

    it "should have a name" do
      @relation.name.should == :users
    end

    it "should have an engine" do
      @relation.engine.should == Table.engine
    end

    describe '[]' do
      describe 'when given a', Symbol do
        it "manufactures an attribute if the symbol names an attribute within the relation" do
          column = @relation[:id]
          check column.name.should == 'id'
          column.should be_kind_of Attributes::Integer
        end
      end

      ### FIXME: this seems like a bad requirement.
      #describe 'when given an', Attribute do
      #  it "returns the attribute if the attribute is within the relation" do
      #    @relation[@relation[:id]].should == @relation[:id]
      #  end

      #  it "returns nil if the attribtue is not within the relation" do
      #    another_relation = Table.new(:photos)
      #    @relation[another_relation[:id]].should be_nil
      #  end
      #end

      #describe 'when given an', Expression do
      #  before do
      #    @expression = @relation[:id].count
      #  end

      #  it "returns the Expression if the Expression is within the relation" do
      #    @relation[@expression].should be_nil
      #  end
      #end
    end
  end
end