dump_schema_information: explicitly order inserts into schema_migrations table

This change reduces churn in the db/development_structure.sql file when using :sql as
active_record.schema_format, and makes comparing diffs much easier.

Test ensures the output SQL-statements are lexically ordered by version.

2 files changed, 10 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index b4a9e29ef1..910ef3efce 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -405,7 +405,7 @@ module ActiveRecord
 
       def dump_schema_information #:nodoc:
         sm_table = ActiveRecord::Migrator.schema_migrations_table_name
-        migrated = select_values("SELECT version FROM #{sm_table}")
+        migrated = select_values("SELECT version FROM #{sm_table} ORDER BY version")
         migrated.map { |v| "INSERT INTO #{sm_table} (version) VALUES ('#{v}');" }.join("\n\n")
       end
 
diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 49944eced9..4fdb7d2f25 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -1339,6 +1339,15 @@ if ActiveRecord::Base.connection.supports_migrations?
       end
     end
 
+    def test_dump_schema_information_outputs_lexically_ordered_versions
+      migration_path = MIGRATIONS_ROOT + '/valid_with_timestamps'
+      ActiveRecord::Migrator.run(:up, migration_path, 20100301010101)
+      ActiveRecord::Migrator.run(:up, migration_path, 20100201010101)
+
+      schema_info = ActiveRecord::Base.connection.dump_schema_information
+      assert_match schema_info, /20100201010101.*20100301010101/m
+    end
+
     def test_finds_pending_migrations
       ActiveRecord::Migrator.up(MIGRATIONS_ROOT + "/interleaved/pass_2", 1)
       migrations = ActiveRecord::Migrator.new(:up, MIGRATIONS_ROOT + "/interleaved/pass_2").pending_migrations