pg, correctly dump foreign keys targeting tables in a different schema.

Closes #16907.

[Matthew Draper & Yves Senn]

3 files changed, 35 insertions, 1 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 40eb32c059..945e3bb2e3 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,10 @@
+*   PostgreSQL adapter correctly dumps foreign keys targeting tables
+    outside the schema search path.
+
+    Fixes #16907.
+
+    *Matthew Draper*, *Yves Senn*
+
 *   When a thread is killed, rollback the active transaction, instead of
     committing it during the stack unwind. Previously, we could commit half-
     completed work. This fix only works for Ruby 2.0+; on 1.9, we can't
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index 767b6b614a..fda5bbad5c 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -466,7 +466,7 @@ module ActiveRecord
 
         def foreign_keys(table_name)
           fk_info = select_all <<-SQL.strip_heredoc
-            SELECT t2.relname AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete
+            SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete
             FROM pg_constraint c
             JOIN pg_class t1 ON c.conrelid = t1.oid
             JOIN pg_class t2 ON c.confrelid = t2.oid
@@ -488,6 +488,7 @@ module ActiveRecord
 
             options[:on_delete] = extract_foreign_key_action(row['on_delete'])
             options[:on_update] = extract_foreign_key_action(row['on_update'])
+
             ForeignKeyDefinition.new(table_name, row['to_table'], options)
           end
         end
diff --git a/activerecord/test/cases/adapters/postgresql/schema_test.rb b/activerecord/test/cases/adapters/postgresql/schema_test.rb
index 9e5fd17dc4..6f40b0d2de 100644
--- a/activerecord/test/cases/adapters/postgresql/schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/schema_test.rb
@@ -1,4 +1,5 @@
 require "cases/helper"
+require 'support/schema_dumping_helper'
 
 class SchemaTest < ActiveRecord::TestCase
   self.use_transactional_fixtures = false
@@ -426,3 +427,28 @@ class SchemaTest < ActiveRecord::TestCase
       assert_equal this_index_name, this_index.name
     end
 end
+
+class SchemaForeignKeyTest < ActiveRecord::TestCase
+  include SchemaDumpingHelper
+
+  setup do
+    @connection = ActiveRecord::Base.connection
+  end
+
+  def test_dump_foreign_key_targeting_different_schema
+    @connection.create_schema "my_schema"
+    @connection.create_table "my_schema.trains" do |t|
+      t.string :name
+    end
+    @connection.create_table "wagons" do |t|
+      t.integer :train_id
+    end
+    @connection.add_foreign_key "wagons", "my_schema.trains", column: "train_id"
+    output = dump_table_schema "wagons"
+    assert_match %r{\s+add_foreign_key "wagons", "my_schema.trains", column: "train_id"$}, output
+  ensure
+    @connection.execute "DROP TABLE IF EXISTS wagons"
+    @connection.execute "DROP TABLE IF EXISTS my_schema.trains"
+    @connection.execute "DROP SCHEMA IF EXISTS my_schema"
+  end
+end