From: Tom Hughes <tom@compton.nu>
Date: Mon, 14 Oct 2013 23:17:39 +0000 (+0100)
Subject: Monkey patch composite_primary_keys to fix deletes via has_many
X-Git-Tag: live~5212
X-Git-Url: https://git.openstreetmap.org./rails.git/commitdiff_plain/b0936b87f422138579352c4f2778ecbcfe0118bf

Monkey patch composite_primary_keys to fix deletes via has_many

https://github.com/composite-primary-keys/composite_primary_keys/pull/170
---

diff --git a/config/initializers/composite_primary_keys.rb b/config/initializers/composite_primary_keys.rb
new file mode 100644
index 000000000..ed4d5f2c9
--- /dev/null
+++ b/config/initializers/composite_primary_keys.rb
@@ -0,0 +1,48 @@
+# Monkey patch composite_primary_keys pending the resolution of:
+# https://github.com/composite-primary-keys/composite_primary_keys/pull/170
+module ActiveRecord
+  module Associations
+    class HasManyAssociation
+      def delete_records(records, method)
+        if method == :destroy
+          records.each { |r| r.destroy }
+          update_counter(-records.length) unless inverse_updates_counter_cache?
+        else
+          if records == :all
+            scope = self.scope
+          else
+            # CPK
+            # keys  = records.map { |r| r[reflection.association_primary_key] }
+            # scope = scope.where(reflection.association_primary_key => keys)
+            table = Arel::Table.new(reflection.table_name)
+            and_conditions = records.map do |record|
+              eq_conditions = Array(reflection.association_primary_key).map do |name|
+                table[name].eq(record[name])
+              end
+              Arel::Nodes::And.new(eq_conditions)
+            end
+
+            condition = and_conditions.shift
+            and_conditions.each do |and_condition|
+              condition = condition.or(and_condition)
+            end
+
+            scope = self.scope.where(condition)
+          end
+
+          if method == :delete_all
+            update_counter(-scope.delete_all)
+          else
+            # CPK
+            # update_counter(-scope.update_all(reflection.foreign_key => nil))
+            updates = Array(reflection.foreign_key).inject(Hash.new) do |hash, name|
+              hash[name] = nil
+              hash
+            end
+            update_counter(-scope.update_all(updates))
+          end
+        end
+      end
+    end
+  end
+end