Remove `engine` from `TreeManager` and subclasses

This constructor parameter was unused for everything except the
convenience methods `to_sql` and `where_sql`. We can pass the engine
into those methods directly.

lib/arel/crud.rb

@@ -3,7 +3,7 @@ module Arel
   # FIXME hopefully we can remove this
   module Crud
     def compile_update values, pk
-      um = UpdateManager.new @engine
+      um = UpdateManager.new
 
       if Nodes::SqlLiteral === values
         relation = @ctx.from
@@ -26,11 +26,11 @@ def compile_insert values
     end
 
     def create_insert
-      InsertManager.new @engine
+      InsertManager.new
     end
 
     def compile_delete
-      dm = DeleteManager.new @engine
+      dm = DeleteManager.new
       dm.wheres = @ctx.wheres
       dm.from @ctx.froms
       dm

lib/arel/delete_manager.rb

 module Arel
   class DeleteManager < Arel::TreeManager
-    def initialize engine
+    def initialize
       super
       @ast = Nodes::DeleteStatement.new
       @ctx = @ast

lib/arel/insert_manager.rb

 module Arel
   class InsertManager < Arel::TreeManager
-    def initialize engine
+    def initialize
       super
       @ast = Nodes::InsertStatement.new
     end

lib/arel/nodes/table_alias.rb

@@ -12,10 +12,6 @@ def [] name
       def table_name
         relation.respond_to?(:name) ? relation.name : name
       end
-
-      def engine
-        relation.engine
-      end
     end
   end
 end

lib/arel/select_manager.rb

@@ -6,8 +6,8 @@ class SelectManager < Arel::TreeManager
 
     STRING_OR_SYMBOL_CLASS = [Symbol, String]
 
-    def initialize engine, table = nil
-      super(engine)
+    def initialize table = nil
+      super()
       @ast   = Nodes::SelectStatement.new
       @ctx    = @ast.cores.last
       from table
@@ -176,10 +176,10 @@ def orders
       @ast.orders
     end
 
-    def where_sql
+    def where_sql engine = Table.engine
       return if @ctx.wheres.empty?
 
-      viz = Visitors::WhereSql.new @engine.connection
+      viz = Visitors::WhereSql.new engine.connection
       Nodes::SqlLiteral.new viz.accept(@ctx, Collectors::SQLString.new).value
     end
 

lib/arel/table.rb

@@ -6,7 +6,7 @@ class Table
     @engine = nil
     class << self; attr_accessor :engine; end
 
-    attr_accessor :name, :engine, :aliases, :table_alias
+    attr_accessor :name, :aliases, :table_alias
 
     # TableAlias and Table both have a #table_name which is the name of the underlying table
     alias :table_name :name
@@ -15,7 +15,6 @@ def initialize name, options = {}
       @name    = name.to_s
       @columns = nil
       @aliases = []
-      @engine = Table.engine
 
       # Sometime AR sends an :as parameter to table, to let the table know
       # that it is an Alias.  We may want to override new, and return a
@@ -32,8 +31,8 @@ def alias name = "#{self.name}_2"
       end
     end
 
-    def from engine = Table.engine
-      SelectManager.new(engine, self)
+    def from
+      SelectManager.new(self)
     end
 
     def join relation, klass = Nodes::InnerJoin

lib/arel/tree_manager.rb

@@ -8,8 +8,7 @@ class TreeManager
 
     attr_accessor :bind_values
 
-    def initialize engine
-      @engine = engine
+    def initialize
       @ctx    = nil
       @bind_values = []
     end
@@ -20,13 +19,9 @@ def to_dot
       collector.value
     end
 
-    def visitor
-      engine.connection.visitor
-    end
-
-    def to_sql
+    def to_sql engine = Table.engine
       collector = Arel::Collectors::SQLString.new
-      collector = visitor.accept @ast, collector
+      collector = engine.connection.visitor.accept @ast, collector
       collector.value
     end
 

lib/arel/update_manager.rb

 module Arel
   class UpdateManager < Arel::TreeManager
-    def initialize engine
+    def initialize
       super
       @ast = Nodes::UpdateStatement.new
       @ctx = @ast

test/collectors/test_bind_collector.rb

@@ -20,7 +20,7 @@ def compile node
 
       def ast_with_binds bv
         table = Table.new(:users)
-        manager = Arel::SelectManager.new Table.engine, table
+        manager = Arel::SelectManager.new table
         manager.where(table[:age].eq(bv))
         manager.where(table[:name].eq(bv))
         manager.ast

test/collectors/test_sql_string.rb

@@ -20,7 +20,7 @@ def compile node
 
       def ast_with_binds bv
         table = Table.new(:users)
-        manager = Arel::SelectManager.new Table.engine, table
+        manager = Arel::SelectManager.new table
         manager.where(table[:age].eq(bv))
         manager.where(table[:name].eq(bv))
         manager.ast

test/nodes/test_table_alias.rb

@@ -4,13 +4,6 @@
 module Arel
   module Nodes
     describe 'table alias' do
-      it 'has an #engine which delegates to the relation' do
-        relation = OpenStruct.new(engine: 'vroom')
-
-        node = TableAlias.new relation, :foo
-        node.engine.must_equal 'vroom'
-      end
-
       describe 'equality' do
         it 'is equal with equal ivars' do
           relation1 = Table.new(:users)

test/test_delete_manager.rb

@@ -4,21 +4,21 @@ module Arel
   describe 'delete manager' do
     describe 'new' do
       it 'takes an engine' do
-        Arel::DeleteManager.new Table.engine
+        Arel::DeleteManager.new
       end
     end
 
     describe 'from' do
       it 'uses from' do
         table = Table.new(:users)
-        dm = Arel::DeleteManager.new Table.engine
+        dm = Arel::DeleteManager.new
         dm.from table
         dm.to_sql.must_be_like %{ DELETE FROM "users" }
       end
 
       it 'chains' do
         table = Table.new(:users)
-        dm = Arel::DeleteManager.new Table.engine
+        dm = Arel::DeleteManager.new
         dm.from(table).must_equal dm
       end
     end
@@ -26,7 +26,7 @@ module Arel
     describe 'where' do
       it 'uses where values' do
         table = Table.new(:users)
-        dm = Arel::DeleteManager.new Table.engine
+        dm = Arel::DeleteManager.new
         dm.from table
         dm.where table[:id].eq(10)
         dm.to_sql.must_be_like %{ DELETE FROM "users" WHERE "users"."id" = 10}
@@ -34,7 +34,7 @@ module Arel
 
       it 'chains' do
         table = Table.new(:users)
-        dm = Arel::DeleteManager.new Table.engine
+        dm = Arel::DeleteManager.new
         dm.where(table[:id].eq(10)).must_equal dm
       end
     end

test/test_insert_manager.rb

@@ -4,13 +4,13 @@ module Arel
   describe 'insert manager' do
     describe 'new' do
       it 'takes an engine' do
-        Arel::InsertManager.new Table.engine
+        Arel::InsertManager.new
       end
     end
 
     describe 'insert' do
       it 'can create a Values node' do
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         values  = manager.create_values %w{ a b }, %w{ c d }
 
         assert_kind_of Arel::Nodes::Values, values
@@ -19,7 +19,7 @@ module Arel
       end
 
       it 'allows sql literals' do
-        manager        = Arel::InsertManager.new Table.engine
+        manager        = Arel::InsertManager.new
         manager.into Table.new(:users)
         manager.values = manager.create_values [Arel.sql('*')], %w{ a }
         manager.to_sql.must_be_like %{
@@ -29,7 +29,7 @@ module Arel
 
       it "inserts false" do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
 
         manager.insert [[table[:bool], false]]
         manager.to_sql.must_be_like %{
@@ -39,7 +39,7 @@ module Arel
 
       it "inserts null" do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.insert [[table[:id], nil]]
         manager.to_sql.must_be_like %{
           INSERT INTO "users" ("id") VALUES (NULL)
@@ -48,7 +48,7 @@ module Arel
 
       it "inserts time" do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
 
         time = Time.now
         attribute = table[:created_at]
@@ -61,7 +61,7 @@ module Arel
 
       it 'takes a list of lists' do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
         manager.insert [[table[:id], 1], [table[:name], 'aaron']]
         manager.to_sql.must_be_like %{
@@ -71,7 +71,7 @@ module Arel
 
       it 'defaults the table' do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.insert [[table[:id], 1], [table[:name], 'aaron']]
         manager.to_sql.must_be_like %{
           INSERT INTO "users" ("id", "name") VALUES (1, 'aaron')
@@ -80,7 +80,7 @@ module Arel
 
       it 'noop for empty list' do
         table = Table.new(:users)
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.insert [[table[:id], 1]]
         manager.insert []
         manager.to_sql.must_be_like %{
@@ -91,13 +91,13 @@ module Arel
 
     describe 'into' do
       it 'takes a Table and chains' do
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into(Table.new(:users)).must_equal manager
       end
 
       it 'converts to sql' do
         table   = Table.new :users
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
         manager.to_sql.must_be_like %{
           INSERT INTO "users"
@@ -108,7 +108,7 @@ module Arel
     describe 'columns' do
       it "converts to sql" do
         table   = Table.new :users
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
         manager.columns << table[:id]
         manager.to_sql.must_be_like %{
@@ -120,7 +120,7 @@ module Arel
     describe "values" do
       it "converts to sql" do
         table   = Table.new :users
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
 
         manager.values = Nodes::Values.new [1]
@@ -133,7 +133,7 @@ module Arel
     describe "combo" do
       it "combines columns and values list in order" do
         table   = Table.new :users
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
 
         manager.values = Nodes::Values.new [1, 'aaron']
@@ -150,10 +150,10 @@ module Arel
       it "accepts a select query in place of a VALUES clause" do
         table   = Table.new :users
 
-        manager = Arel::InsertManager.new Table.engine
+        manager = Arel::InsertManager.new
         manager.into table
 
-        select = Arel::SelectManager.new Table.engine
+        select = Arel::SelectManager.new
         select.project Arel.sql('1')
         select.project Arel.sql('"aaron"')
 

test/test_table.rb

@@ -179,10 +179,6 @@ module Arel
       @relation.table_name.must_equal 'users'
     end
 
-    it "should have an engine" do
-      @relation.engine.must_equal 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

test/test_update_manager.rb

@@ -4,13 +4,13 @@ module Arel
   describe 'update manager' do
     describe 'new' do
       it 'takes an engine' do
-        Arel::UpdateManager.new Table.engine
+        Arel::UpdateManager.new
       end
     end
 
     it "should not quote sql literals" do
       table = Table.new(:users)
-      um = Arel::UpdateManager.new Table.engine
+      um = Arel::UpdateManager.new
       um.table table
       um.set [[table[:name], Arel::Nodes::BindParam.new]]
       um.to_sql.must_be_like %{ UPDATE "users" SET "name" =  ? }
@@ -18,7 +18,7 @@ module Arel
 
     it 'handles limit properly' do
       table = Table.new(:users)
-      um = Arel::UpdateManager.new Table.engine
+      um = Arel::UpdateManager.new
       um.key = 'id'
       um.take 10
       um.table table
@@ -29,7 +29,7 @@ module Arel
     describe 'set' do
       it "updates with null" do
         table = Table.new(:users)
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table table
         um.set [[table[:name], nil]]
         um.to_sql.must_be_like %{ UPDATE "users" SET "name" =  NULL }
@@ -37,7 +37,7 @@ module Arel
 
       it 'takes a string' do
         table = Table.new(:users)
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table table
         um.set Nodes::SqlLiteral.new "foo = bar"
         um.to_sql.must_be_like %{ UPDATE "users" SET foo = bar }
@@ -45,7 +45,7 @@ module Arel
 
       it 'takes a list of lists' do
         table = Table.new(:users)
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table table
         um.set [[table[:id], 1], [table[:name], 'hello']]
         um.to_sql.must_be_like %{
@@ -55,25 +55,25 @@ module Arel
 
       it 'chains' do
         table = Table.new(:users)
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.set([[table[:id], 1], [table[:name], 'hello']]).must_equal um
       end
     end
 
     describe 'table' do
       it 'generates an update statement' do
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table Table.new(:users)
         um.to_sql.must_be_like %{ UPDATE "users" }
       end
 
       it 'chains' do
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table(Table.new(:users)).must_equal um
       end
 
       it 'generates an update statement with joins' do
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
 
         table = Table.new(:users)
         join_source = Arel::Nodes::JoinSource.new(
@@ -89,7 +89,7 @@ module Arel
     describe 'where' do
       it 'generates a where clause' do
         table = Table.new :users
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table table
         um.where table[:id].eq(1)
         um.to_sql.must_be_like %{
@@ -99,7 +99,7 @@ module Arel
 
       it 'chains' do
         table = Table.new :users
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         um.table table
         um.where(table[:id].eq(1)).must_equal um
       end
@@ -108,7 +108,7 @@ module Arel
     describe 'key' do
       before do
         @table = Table.new :users
-        @um = Arel::UpdateManager.new Table.engine
+        @um = Arel::UpdateManager.new
         @um.key = @table[:foo]
       end
 

test/visitors/test_bind_visitor.rb

@@ -17,7 +17,7 @@ def setup
       # substitutes binds with values from block
       def test_assignment_binds_are_substituted
         table = Table.new(:users)
-        um = Arel::UpdateManager.new Table.engine
+        um = Arel::UpdateManager.new
         bp = Nodes::BindParam.new
         um.set [[table[:name], bp]]
         visitor = Class.new(Arel::Visitors::ToSql) {