Merge `delegate` calls

src/ameba/ast/scope.cr

@@ -34,9 +34,8 @@ module Ameba::AST
     # The actual AST node that represents a current scope.
     getter node : Crystal::ASTNode
 
-    delegate to_s, to: node
-    delegate location, to: node
-    delegate end_location, to: node
+    delegate location, end_location, to_s,
+      to: @node
 
     def_equals_and_hash node, location
 

src/ameba/ast/variabling/argument.cr

@@ -19,9 +19,8 @@ module Ameba::AST
     # Variable of this argument (may be the same node)
     getter variable : Variable
 
-    delegate location, to: @node
-    delegate end_location, to: @node
-    delegate to_s, to: @node
+    delegate location, end_location, to_s,
+      to: @node
 
     # Creates a new argument.
     #

src/ameba/ast/variabling/assignment.cr

@@ -19,9 +19,8 @@ module Ameba::AST
     # A scope assignment belongs to
     getter scope : Scope
 
-    delegate to_s, to: @node
-    delegate location, to: @node
-    delegate end_location, to: @node
+    delegate location, end_location, to_s,
+      to: @node
 
     # Creates a new assignment.
     #

src/ameba/ast/variabling/ivariable.cr

@@ -2,10 +2,8 @@ module Ameba::AST
   class InstanceVariable
     getter node : Crystal::InstanceVar
 
-    delegate location, to: @node
-    delegate end_location, to: @node
-    delegate name, to: @node
-    delegate to_s, to: @node
+    delegate location, end_location, name, to_s,
+      to: @node
 
     def initialize(@node)
     end

src/ameba/ast/variabling/type_dec_variable.cr

@@ -2,9 +2,8 @@ module Ameba::AST
   class TypeDecVariable
     getter node : Crystal::TypeDeclaration
 
-    delegate location, to: @node
-    delegate end_location, to: @node
-    delegate to_s, to: @node
+    delegate location, end_location, to_s,
+      to: @node
 
     def initialize(@node)
     end

src/ameba/ast/variabling/variable.cr

@@ -17,10 +17,8 @@ module Ameba::AST
     # Node of the first assignment which can be available before any reference.
     getter assign_before_reference : Crystal::ASTNode?
 
-    delegate location, to: @node
-    delegate end_location, to: @node
-    delegate name, to: @node
-    delegate to_s, to: @node
+    delegate location, end_location, name, to_s,
+      to: @node
 
     # Creates a new variable(in the scope).
     #