Add association_primary to has_and_belongs_to_many

src/jennifer/model/relation_definition.cr

@@ -226,6 +226,7 @@ module Jennifer
       # - *primary* - specify the name of the column to use as the primary key for the relation
       # - *join_table* - specifies the name of the join table if the default based on lexical order isn't what you want
       # - *association_foreign* - specifies the foreign key used for the association on the receiving side of the association
+      # - *association_primary* - specifies the primary key used for the association on the receiving side of the association
       #
       # The following methods for retrieval and query of a single associated object will be added:
       #
@@ -238,11 +239,11 @@ module Jennifer
       # - `#remove_association(rel)`
       # - `#association_query`
       # - `#association_reload`
-      macro has_and_belongs_to_many(name, klass, request = nil, foreign = nil, primary = nil, join_table = nil, association_foreign = nil)
+      macro has_and_belongs_to_many(name, klass, request = nil, foreign = nil, primary = nil, join_table = nil, association_foreign = nil, association_primary = nil)
         {{"{% RELATION_NAMES << #{name.id.stringify} %}".id}}
         RELATIONS["{{name.id}}"] =
           ::Jennifer::Relation::ManyToMany({{klass}}, {{@type}}).new("{{name.id}}", {{foreign}}, {{primary}},
-            {{klass}}.all{% if request %}.exec {{request}} {% end %}, {{join_table}}, {{association_foreign}})
+            {{klass}}.all{% if request %}.exec {{request}} {% end %}, {{join_table}}, {{association_foreign}}, {{association_primary}})
 
         before_destroy :__{{name.id}}_clean
 

src/jennifer/relation/many_to_many.cr

@@ -1,10 +1,11 @@
 module Jennifer
   module Relation
     class ManyToMany(T, Q) < Base(T, Q)
-      getter join_table : String?, association_foreign : String?
+      getter join_table : String?, association_foreign : String?, association_primary : String?
 
-      def initialize(@name, foreign : String | Symbol?, primary : String | Symbol?, query, @join_table = nil, _join_foreign = nil)
+      def initialize(@name, foreign : String | Symbol?, primary : String | Symbol?, query, @join_table = nil, _join_foreign = nil, _join_primary = nil)
         @association_foreign = _join_foreign.to_s if _join_foreign
+        @association_primary = _join_primary.to_s if _join_primary
         @foreign = foreign.to_s if foreign
         @primary = primary.to_s if primary
         @join_query = query.tree
@@ -39,10 +40,11 @@ module Jennifer
 
       def query(primary_value)
         afk = association_foreign_key
+        apk = association_primary_key
         _primary_value = primary_value
         mfk = foreign_field
         q = T.all.join(join_table!) do
-          (c(afk) == T.primary) &
+          (c(afk) == apk) &
             (_primary_value.is_a?(Array) ? c(mfk).in(_primary_value) : c(mfk) == _primary_value)
         end
         if @join_query
@@ -72,6 +74,14 @@ module Jennifer
         @association_foreign || Inflector.foreign_key(T.to_s)
       end
 
+      def association_primary_key
+        if (association_primary = @association_primary)
+          return Jennifer::QueryBuilder::Criteria.new(association_primary, T.table_name)
+        end
+
+        T.primary
+      end
+
       def preload_relation(collection, out_collection : Array(Model::Resource), pk_repo)
         return if collection.empty?
         _primary = primary_field