Initial work on 4.0.0 compatibility. Specs pass.

This work will not be backwards compatible with 3.x at the moment.

References #239

.ruby-gemset

@@ -0,0 +1 @@
+squeel

.ruby-version

@@ -0,0 +1 @@
+ruby-1.9.3-p374

.travis.yml

@@ -1,13 +1,5 @@
 rvm:
-  - 1.8.7
   - 1.9.3
-# TODO: Re-enable when updates to Rubinius on
-# Travis stop randomly breaking specs that
-# pass on MRI. :(
-#  - rbx-18mode
-#  - rbx-19mode
 
 env:
-  - RAILS=3-2-stable
-  - RAILS=3-1-stable AREL=2-2-stable
-  - RAILS=3-0-stable AREL=2-0-stable
+  - RAILS=4-0-stable AREL=master

Gemfile

@@ -3,8 +3,8 @@ gemspec
 
 gem 'rake'
 
-rails = ENV['RAILS'] || '3-2-stable'
-arel = ENV['AREL'] || '3-0-stable'
+rails = ENV['RAILS'] || '4-0-stable'
+arel = ENV['AREL'] || 'master'
 
 arel_opts = case arel
 when /\// # A path

lib/squeel/adapters/active_record.rb

@@ -1,5 +1,5 @@
 case ActiveRecord::VERSION::MAJOR
-when 3
+when 3, 4
   ActiveRecord::Relation.send :include, Squeel::Nodes::Aliasing
   require 'squeel/adapters/active_record/join_dependency_extensions'
   require 'squeel/adapters/active_record/base_extensions'

lib/squeel/adapters/active_record/4.0/association_scope_extensions.rb

@@ -0,0 +1,13 @@
+module ActiveRecord
+  module Associations
+    class AssociationScope
+      def eval_scope(klass, scope)
+        if scope.is_a?(Relation)
+          scope
+        else
+          klass.unscoped.instance_exec(owner, &scope).visited
+        end
+      end
+    end
+  end
+end

lib/squeel/adapters/active_record/4.0/compat.rb

@@ -0,0 +1 @@
+require 'squeel/adapters/active_record/compat'

lib/squeel/adapters/active_record/4.0/context.rb

@@ -0,0 +1 @@
+require 'squeel/adapters/active_record/context'

lib/squeel/adapters/active_record/4.0/preloader_extensions.rb

@@ -0,0 +1 @@
+require 'squeel/adapters/active_record/preloader_extensions'

lib/squeel/adapters/active_record/4.0/relation_extensions.rb

@@ -0,0 +1,75 @@
+require 'squeel/adapters/active_record/relation_extensions'
+
+module Squeel
+  module Adapters
+    module ActiveRecord
+      module RelationExtensions
+
+        def where(opts = :chain, *rest)
+          if block_given?
+            super(DSL.eval &Proc.new)
+          else
+            super
+          end
+        end
+
+        def build_arel
+          arel = Arel::SelectManager.new(table.engine, table)
+
+          build_joins(arel, joins_values) unless joins_values.empty?
+
+          collapse_wheres(arel, where_visit((where_values - ['']).uniq))
+
+          arel.having(*having_visit(having_values.uniq.reject{|h| h.blank?})) unless having_values.empty?
+
+          arel.take(connection.sanitize_limit(limit_value)) if limit_value
+          arel.skip(offset_value.to_i) if offset_value
+
+          arel.group(*group_visit(group_values.uniq.reject{|g| g.blank?})) unless group_values.empty?
+
+          build_order(arel)
+
+          build_select(arel, select_visit(select_values.uniq))
+
+          arel.distinct(distinct_value)
+          arel.from(from_visit(from_value)) if from_value
+          arel.lock(lock_value) if lock_value
+
+          arel
+        end
+
+        def build_order(arel)
+          orders = order_visit(order_values)
+          orders = reverse_sql_order(attrs_to_orderings(orders)) if reverse_order_value
+
+          orders = orders.uniq.reject(&:blank?).flat_map do |order|
+            case order
+            when Symbol
+              table[order].asc
+            when Hash
+              order.map { |field, dir| table[field].send(dir) }
+            else
+              order
+            end
+          end
+
+          arel.order(*orders) unless orders.empty?
+        end
+
+        def build_from
+          opts, name = from_value
+          case opts
+          when Relation
+            name ||= 'subquery'
+            opts.arel.as(name.to_s)
+          else
+            opts
+          end
+        end
+
+      end
+    end
+  end
+end
+
+ActiveRecord::Relation.send :include, Squeel::Adapters::ActiveRecord::RelationExtensions

lib/squeel/adapters/active_record/context.rb

@@ -44,6 +44,16 @@ def traverse(keypath, parent = @base, include_endpoint = false)
           parent
         end
 
+        def classify(object)
+          if Class === object
+            object
+          elsif object.respond_to? :base_klass
+            object.base_klass
+          else
+            raise ArgumentError, "#{object} can't be converted to a class"
+          end
+        end
+
         private
 
         def get_table(object)
@@ -58,16 +68,6 @@ def get_table(object)
           end
         end
 
-        def classify(object)
-          if Class === object
-            object
-          elsif object.respond_to? :active_record
-            object.active_record
-          else
-            raise ArgumentError, "#{object} can't be converted to a class"
-          end
-        end
-
         def get_arel_visitor
           @engine.connection.visitor
         end

lib/squeel/adapters/active_record/relation_extensions.rb

@@ -14,7 +14,12 @@ module RelationExtensions
         # because the default #reset already does this, despite never setting
         # it anywhere that I can find. Serendipity, I say!
         def join_dependency
-          @join_dependency ||= (build_join_dependency(table.from(table), @joins_values) && @join_dependency)
+          @join_dependency ||= (
+            build_join_dependency(
+              Arel::SelectManager.new(table.engine, table),
+              joins_values
+            ) && @join_dependency
+          )
         end
 
         %w(where having group order select from).each do |visitor|
@@ -49,12 +54,12 @@ def visited
         end
 
         def visit!
-          @where_values = where_visit((@where_values - ['']).uniq)
-          @having_values = having_visit(@having_values.uniq.reject{|h| h.blank?})
+          self.where_values = where_visit((where_values - ['']).uniq)
+          self.having_values = having_visit(having_values.uniq.reject{|h| h.blank?})
           # FIXME: AR barfs on ARel attributes in group_values. Workaround?
-          # @group_values = group_visit(@group_values.uniq.reject{|g| g.blank?})
-          @order_values = order_visit(@order_values.uniq.reject{|o| o.blank?})
-          @select_values = select_visit(@select_values.uniq)
+          # self.group_values = group_visit(group_values.uniq.reject{|g| g.blank?})
+          self.order_values = order_visit(order_values.uniq.reject{|o| o.blank?})
+          self.select_values = select_visit(select_values.uniq)
 
           self
         end
@@ -100,22 +105,22 @@ def build_join_dependency(manager, joins)
           buckets = joins.group_by do |join|
             case join
             when String
-              'string_join'
+              :string_join
             when Hash, Symbol, Array, Nodes::Stub, Nodes::Join, Nodes::KeyPath
-              'association_join'
+              :association_join
             when JoinAssociation
-              'stashed_join'
+              :stashed_join
             when Arel::Nodes::Join
-              'join_node'
+              :join_node
             else
               raise 'unknown class: %s' % join.class.name
             end
           end
 
-          association_joins         = buckets['association_join'] || []
-          stashed_association_joins = buckets['stashed_join'] || []
-          join_nodes                = (buckets['join_node'] || []).uniq
-          string_joins              = (buckets['string_join'] || []).map { |x|
+          association_joins         = buckets[:association_join] || []
+          stashed_association_joins = buckets[:stashed_join] || []
+          join_nodes                = (buckets[:join_node] || []).uniq
+          string_joins              = (buckets[:string_join] || []).map { |x|
             x.strip
           }.uniq
 
@@ -140,6 +145,8 @@ def build_join_dependency(manager, joins)
 
           manager
         end
+        # For 4.x adapters
+        alias :build_joins :build_join_dependency
 
         def includes(*args)
           if block_given? && args.empty?
@@ -335,7 +342,7 @@ def resolve_duplicate_squeel_equalities(wheres)
         # DB for debug purposes without actually running the query.
         def debug_sql
           if eager_loading?
-            including = (@eager_load_values + @includes_values).uniq
+            including = (eager_load_values + includes_values).uniq
             join_dependency = JoinDependency.new(@klass, including, [])
             construct_relation_for_association_find(join_dependency).to_sql
           else

lib/squeel/nodes.rb

@@ -5,6 +5,8 @@ module Nodes
   end
 end
 
+require 'squeel/nodes/node'
+
 require 'squeel/nodes/predicate_methods'
 require 'squeel/nodes/operators'
 require 'squeel/nodes/predicate_operators'

lib/squeel/nodes/binary.rb

@@ -1,7 +1,7 @@
 module Squeel
   module Nodes
     # A node that represents an operation with two operands.
-    class Binary
+    class Binary < Node
 
       include PredicateOperators
 

lib/squeel/nodes/function.rb

@@ -1,7 +1,7 @@
 module Squeel
   module Nodes
     # A node that represents an SQL function call
-    class Function
+    class Function < Node
 
       include PredicateMethods
       include PredicateOperators
@@ -22,16 +22,16 @@ class Function
       alias :<= :lteq
 
       # @return [Symbol] The name of the SQL function to be called
-      attr_reader :name
+      attr_reader :function_name
 
       # @return [Array] The arguments to be passed to the SQL function
       attr_reader :args
 
       # Create a node representing an SQL Function with the given name and arguments
       # @param [Symbol] name The function name
       # @param [Array] args The array of arguments to pass to the function.
-      def initialize(name, args)
-        @name, @args = name, args
+      def initialize(function_name, args)
+        @function_name, @args = function_name, args
       end
 
       # expand_hash_conditions_for_aggregates assumes our hash keys can be
@@ -48,7 +48,7 @@ def hash
 
       def eql?(other)
         self.class == other.class &&
-          self.name.eql?(other.name) &&
+          self.function_name.eql?(other.function_name) &&
           self.args.eql?(other.args)
       end
 

lib/squeel/nodes/join.rb

@@ -3,7 +3,7 @@
 module Squeel
   module Nodes
     # A node representing a joined association
-    class Join
+    class Join < Node
       undef_method :id if method_defined?(:id)
 
       attr_reader :_join

lib/squeel/nodes/key_path.rb

@@ -4,7 +4,7 @@ module Squeel
   module Nodes
     # A node that stores a path of keys (of Symbol, Stub, or Join values) and
     # an endpoint. Used similarly to a nested hash.
-    class KeyPath
+    class KeyPath < Node
       include PredicateOperators
       include Operators
 
@@ -179,12 +179,17 @@ def to_s
 
       # Appends to the KeyPath or delegates to the endpoint, as appropriate
       # @return [KeyPath] The updated KeyPath
-      def method_missing(method_id, *args)
+      def method_missing(method_id, *args, &block)
         super if method_id == :to_ary
 
-        if endpoint.respond_to? method_id
-          self.endpoint = endpoint.send(method_id, *args)
-          self
+        if endpoint.respond_to?(method_id)
+          if Predicate === endpoint && method_id == :==
+            false
+          else
+            # TODO: We really should not mutate here.
+            self.endpoint = endpoint.send(method_id, *args)
+            self
+          end
         elsif Stub === endpoint || Join === endpoint
           if args.empty?
             @path << Stub.new(method_id)

lib/squeel/nodes/literal.rb

@@ -1,7 +1,7 @@
 module Squeel
   module Nodes
     # Literal nodes are a container for raw SQL.
-    class Literal
+    class Literal < Node
       include PredicateMethods
       include PredicateOperators
       include Operators

lib/squeel/nodes/nary.rb

@@ -1,7 +1,7 @@
 module Squeel
   module Nodes
     # A node containing multiple children. Just the And node for now.
-    class Nary
+    class Nary < Node
       include PredicateOperators
 
       # @return [Array] This node's children

lib/squeel/nodes/node.rb

@@ -0,0 +1,6 @@
+module Squeel
+  module Nodes
+    class Node
+    end
+  end
+end

lib/squeel/nodes/operation.rb

@@ -15,7 +15,7 @@ def initialize(left, operator, right)
       end
 
       # An operation should probably call its "function" name an "operator", shouldn't it?
-      alias :operator :name
+      alias :operator :function_name
 
       # @return The left operand
       def left

lib/squeel/nodes/order.rb

@@ -1,7 +1,7 @@
 module Squeel
   module Nodes
     # A node that represents SQL orderings, such as "people.id DESC"
-    class Order
+    class Order < Node
       # @return The expression being ordered on. Might be an attribute, function, or operation
       attr_reader :expr
 

lib/squeel/nodes/predicate.rb

@@ -5,7 +5,7 @@ module Nodes
     # operation), the ARel predicate method name, and a value. these are then interpreted
     # when visited by the PredicateVisitor to generate a condition against the appropriate
     # columns.
-    class Predicate
+    class Predicate < Node
 
       include PredicateOperators
       include Aliasing