require 'cases/helper' require 'models/car' require 'active_support/core_ext/string/strip' if ActiveRecord::Base.connection.supports_explain? class ExplainTest < ActiveRecord::TestCase fixtures :cars def base ActiveRecord::Base end def connection base.connection end def test_logging_query_plan_with_logger base.logger.expects(:warn).with do |message| message.starts_with?('EXPLAIN for:') end with_threshold(0) do Car.where(:name => 'honda').all end end def test_logging_query_plan_without_logger original = base.logger base.logger = nil class << base.logger def warn; raise "Should not be called" end end with_threshold(0) do car = Car.where(:name => 'honda').first assert_equal 'honda', car.name end ensure base.logger = original end def test_collect_queries_for_explain base.auto_explain_threshold_in_seconds = nil queries = Thread.current[:available_queries_for_explain] = [] with_threshold(0) do Car.where(:name => 'honda').all end sql, binds = queries[0] assert_match "SELECT", sql assert_match "honda", sql assert_equal [], binds ensure Thread.current[:available_queries_for_explain] = nil end def test_collecting_queries_for_explain result, queries = ActiveRecord::Base.collecting_queries_for_explain do Car.where(:name => 'honda').all end sql, binds = queries[0] assert_match "SELECT", sql assert_match "honda", sql assert_equal [], binds assert_equal [cars(:honda)], result end def test_exec_explain_with_no_binds sqls = %w(foo bar) binds = [[], []] queries = sqls.zip(binds) connection.stubs(:explain).returns('query plan foo', 'query plan bar') expected = sqls.map {|sql| "EXPLAIN for: #{sql}\nquery plan #{sql}"}.join("\n") assert_equal expected, base.exec_explain(queries) end def test_exec_explain_with_binds cols = [Object.new, Object.new] cols[0].expects(:name).returns('wadus') cols[1].expects(:name).returns('chaflan') sqls = %w(foo bar) binds = [[[cols[0], 1]], [[cols[1], 2]]] queries = sqls.zip(binds) connection.stubs(:explain).returns("query plan foo\n", "query plan bar\n") expected = <<-SQL.strip_heredoc EXPLAIN for: #{sqls[0]} [["wadus", 1]] query plan foo EXPLAIN for: #{sqls[1]} [["chaflan", 2]] query plan bar SQL assert_equal expected, base.exec_explain(queries) end def test_unsupported_connection_adapter connection.stubs(:supports_explain?).returns(false) base.logger.expects(:warn).never with_threshold(0) do Car.where(:name => 'honda').to_a end end def test_silence_auto_explain base.expects(:collecting_sqls_for_explain).never base.logger.expects(:warn).never base.silence_auto_explain do with_threshold(0) { Car.all } end end def with_threshold(threshold) current_threshold = base.auto_explain_threshold_in_seconds base.auto_explain_threshold_in_seconds = threshold yield ensure base.auto_explain_threshold_in_seconds = current_threshold end end end