Extract PrimaryKeyQueryable from Queryable (#455)

* Extract PrimaryKeyQueryable from Queryable

* Switch to composition of modules than an inheritance structure

* Remove abstract defs from PrimaryKeyQueryable

Co-authored-by: Jeremy Woertink <jeremywoertink@gmail.com>

src/avram/base_query_template.cr

@@ -6,6 +6,7 @@ class Avram::BaseQueryTemplate
 
       def_clone
       include Avram::Queryable({{ type }})
+      include Avram::PrimaryKeyQueryable({{ type }})
 
       def database : Avram::Database.class
         {{ type }}.database

src/avram/primary_key_queryable.cr

@@ -0,0 +1,21 @@
+require "./errors"
+
+module Avram::PrimaryKeyQueryable(T)
+  macro included
+    def self.find(id)
+      new.find(id)
+    end
+
+    def find(id)
+      id(id).limit(1).first? || raise Avram::RecordNotFoundError.new(model: @@table_name, id: id.to_s)
+    end
+
+    private def with_ordered_query : self
+      if query.ordered?
+        self
+      else
+        id.asc_order
+      end
+    end
+  end
+end

src/avram/queryable.cr

@@ -1,8 +1,6 @@
 module Avram::Queryable(T)
   include Enumerable(T)
 
-  abstract def id
-
   @query : Avram::QueryBuilder?
   setter query
 
@@ -17,10 +15,6 @@ module Avram::Queryable(T)
       new
     end
 
-    def self.find(id)
-      new.find(id)
-    end
-
     def self.first
       new.first
     end
@@ -149,10 +143,6 @@ module Avram::Queryable(T)
     clone.tap &.query.offset(amount)
   end
 
-  def find(id)
-    id(id).limit(1).first? || raise RecordNotFoundError.new(model: @@table_name, id: id.to_s)
-  end
-
   def first?
     with_ordered_query
       .limit(1)
@@ -213,11 +203,7 @@ module Avram::Queryable(T)
   end
 
   private def with_ordered_query : self
-    if query.ordered?
-      self
-    else
-      id.asc_order
-    end
+    self
   end
 
   def to_sql