Drop MySQL 5.5 support

kamipo · kamipo · commit 6b1515aeb964 · 2024-09-07T13:49:42.000+09:00
MySQL 5.5 is the only version that does not support datetime with
precision, which we have supported in the core.
MySQL 5.5 is already EOL in December 2018, so let's drop this support and
clean up the code for it.
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
@@ -1,3 +1,11 @@
+*   Drop MySQL 5.5 support.
+
+    MySQL 5.5 is the only version that does not support datetime with precision,
+    which we have supported in the core. Now we support MySQL 5.6.4 or later, which
+    is the first version to support datetime with precision.
+
+    *Ryuta Kamizono*
+
 *   Make Active Record asynchronous queries compatible with transactional fixtures.
 
     Previously transactional fixtures would disable asynchronous queries, because transactional
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -138,7 +138,7 @@ def supports_views?
       end
 
       def supports_datetime_with_precision?
-        mariadb? || database_version >= "5.6.4"
+        true
       end
 
       def supports_virtual_columns?
@@ -668,8 +668,8 @@ def build_insert_sql(insert) # :nodoc:
       end
 
       def check_version # :nodoc:
-        if database_version < "5.5.8"
-          raise DatabaseVersionError, "Your version of MySQL (#{database_version}) is too old. Active Record supports MySQL >= 5.5.8."
+        if database_version < "5.6.4"
+          raise DatabaseVersionError, "Your version of MySQL (#{database_version}) is too old. Active Record supports MySQL >= 5.6.4."
         end
       end
 
diff --git a/activerecord/test/cases/adapters/abstract_mysql_adapter/datetime_precision_quoting_test.rb b/activerecord/test/cases/adapters/abstract_mysql_adapter/datetime_precision_quoting_test.rb
diff --git a/activerecord/test/cases/calculations_test.rb b/activerecord/test/cases/calculations_test.rb
@@ -1466,8 +1466,6 @@ def test_minimum_and_maximum_on_tz_aware_attributes
   end
 
   def assert_minimum_and_maximum_on_time_attributes(time_class)
-    skip unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
-
     actual = Topic.minimum(:written_on)
     assert_equal Time.utc(2003, 7, 16, 14, 28, 11, 223300), actual
     assert_instance_of time_class, actual
diff --git a/activerecord/test/cases/collection_cache_key_test.rb b/activerecord/test/cases/collection_cache_key_test.rb
@@ -106,7 +106,6 @@ class CollectionCacheKeyTest < ActiveRecord::TestCase
       developers = Developer.where(name: "David")
       cache_key = developers.cache_key
 
-      sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
       developers.update_all(updated_at: Time.now.utc)
 
       assert_not_equal cache_key, developers.cache_key
@@ -116,7 +115,6 @@ class CollectionCacheKeyTest < ActiveRecord::TestCase
       developers = Developer.includes(:projects).where("projects.name": "Active Record")
       cache_key = developers.cache_key
 
-      sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
       developers.update_all(updated_at: Time.now.utc)
 
       assert_not_equal cache_key, developers.cache_key
diff --git a/activerecord/test/cases/date_time_test.rb b/activerecord/test/cases/date_time_test.rb
@@ -72,7 +72,6 @@ def test_assign_in_local_timezone
   end
 
   def test_date_time_with_string_value_with_subsecond_precision
-    skip unless supports_datetime_with_precision?
     string_value = "2017-07-04 14:19:00.5"
     topic = Topic.create(written_on: string_value)
     assert_equal topic, Topic.find_by(written_on: string_value)
diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb
@@ -620,7 +620,6 @@ def test_field_named_field
   end
 
   def test_datetime_attribute_can_be_updated_with_fractional_seconds
-    skip "Fractional seconds are not supported" unless supports_datetime_with_precision?
     in_time_zone "Paris" do
       target = Class.new(ActiveRecord::Base)
       target.table_name = "topics"
diff --git a/activerecord/test/cases/insert_all_test.rb b/activerecord/test/cases/insert_all_test.rb
@@ -479,7 +479,7 @@ def test_upsert_all_touches_updated_at_and_updated_on_when_values_change
   end
 
   def test_upsert_all_respects_updated_at_precision_when_touched_implicitly
-    skip unless supports_insert_on_duplicate_update? && supports_datetime_with_precision?
+    skip unless supports_insert_on_duplicate_update?
 
     Book.insert_all [{ id: 101, name: "Out of the Silent Planet", published_on: Date.new(1938, 4, 1), updated_at: 5.years.ago, updated_on: 5.years.ago }]
 
@@ -569,7 +569,7 @@ def test_upsert_all_implicitly_sets_timestamps_on_create_when_model_record_times
   end
 
   def test_upsert_all_respects_created_at_precision_when_touched_implicitly
-    skip unless supports_insert_on_duplicate_update? && supports_datetime_with_precision?
+    skip unless supports_insert_on_duplicate_update?
 
     # A single upsert can occur exactly at the seconds boundary (when usec is naturally zero), so try multiple times.
     has_subsecond_precision = (1..100).any? do |i|
diff --git a/activerecord/test/cases/integration_test.rb b/activerecord/test/cases/integration_test.rb
@@ -174,7 +174,6 @@ def test_cache_key_for_newer_updated_on
   end
 
   def test_cache_key_format_is_precise_enough
-    skip("Subsecond precision is not supported") unless supports_datetime_with_precision?
     dev = Developer.first
     key = dev.cache_key
     travel_to dev.updated_at + 0.000001 do
@@ -191,7 +190,6 @@ def test_cache_key_format_is_not_too_precise
   end
 
   def test_cache_version_format_is_precise_enough
-    skip("Subsecond precision is not supported") unless supports_datetime_with_precision?
     with_cache_versioning do
       dev = Developer.first
       version = dev.cache_version.to_param
diff --git a/activerecord/test/cases/locking_test.rb b/activerecord/test/cases/locking_test.rb
@@ -179,7 +179,6 @@ def test_touch_existing_lock
     p1 = Person.find(1)
     assert_equal 0, p1.lock_version
 
-    sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
     p1.touch
 
     assert_equal 1, p1.lock_version
@@ -298,7 +297,6 @@ def test_touch_existing_lock_without_default_should_work_with_null_in_the_databa
     assert_equal 0, t1.lock_version
     assert_nil t1.lock_version_before_type_cast
 
-    sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
     t1.touch
 
     assert_equal 1, t1.lock_version
diff --git a/activerecord/test/cases/migration/change_schema_test.rb b/activerecord/test/cases/migration/change_schema_test.rb
@@ -294,8 +294,7 @@ def test_add_column_with_postgresql_datetime_type
         if current_adapter?(:PostgreSQLAdapter)
           assert_equal "timestamp(6) without time zone", column.sql_type
         elsif current_adapter?(:Mysql2Adapter, :TrilogyAdapter)
-          sql_type = supports_datetime_with_precision? ? "datetime(6)" : "datetime"
-          assert_equal sql_type, column.sql_type
+          assert_equal "datetime(6)", column.sql_type
         else
           assert_equal connection.type_to_sql("datetime(6)"), column.sql_type
         end
diff --git a/activerecord/test/cases/migration/foreign_key_test.rb b/activerecord/test/cases/migration/foreign_key_test.rb
@@ -761,8 +761,6 @@ def test_add_foreign_key_with_if_not_exists_not_set
             if current_adapter?(:Mysql2Adapter, :TrilogyAdapter)
               if ActiveRecord::Base.lease_connection.mariadb?
                 assert_match(/Duplicate key on write or update/, error.message)
-              elsif ActiveRecord::Base.lease_connection.database_version < "5.6"
-                assert_match(/Can't create table/, error.message)
               elsif ActiveRecord::Base.lease_connection.database_version < "8.0"
                 assert_match(/Can't write; duplicate key in table/, error.message)
               else
diff --git a/activerecord/test/cases/primary_keys_test.rb b/activerecord/test/cases/primary_keys_test.rb
@@ -351,7 +351,7 @@ def test_any_type_primary_key
     assert_no_match %r{t\.index \["code"\]}, schema
   end
 
-  if current_adapter?(:Mysql2Adapter, :TrilogyAdapter) && supports_datetime_with_precision?
+  if current_adapter?(:Mysql2Adapter, :TrilogyAdapter)
     test "schema typed primary key column" do
       @connection.create_table(:scheduled_logs, id: :timestamp, precision: 6, force: true)
       schema = dump_table_schema("scheduled_logs")
diff --git a/activerecord/test/cases/schema_dumper_test.rb b/activerecord/test/cases/schema_dumper_test.rb
@@ -934,13 +934,7 @@ def test_schema_dump_defaults_with_universally_supported_types
 
     assert_match %r{t\.string\s+"string_with_default",.*?default: "Hello!"}, output
     assert_match %r{t\.date\s+"date_with_default",\s+default: "2014-06-05"}, output
-
-    if supports_datetime_with_precision?
-      assert_match %r{t\.datetime\s+"datetime_with_default",\s+default: "2014-06-05 07:17:04"}, output
-    else
-      assert_match %r{t\.datetime\s+"datetime_with_default",\s+precision: nil,\s+default: "2014-06-05 07:17:04"}, output
-    end
-
+    assert_match %r{t\.datetime\s+"datetime_with_default",\s+default: "2014-06-05 07:17:04"}, output
     assert_match %r{t\.time\s+"time_with_default",\s+default: "2000-01-01 07:17:04"}, output
     assert_match %r{t\.decimal\s+"decimal_with_default",\s+precision: 20,\s+scale: 10,\s+default: "1234567890.0123456789"}, output
   end
diff --git a/activerecord/test/cases/timestamp_test.rb b/activerecord/test/cases/timestamp_test.rb
@@ -34,8 +34,6 @@ def test_saving_a_unchanged_record_doesnt_update_its_timestamp
   end
 
   def test_touching_a_record_updates_its_timestamp
-    sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
-
     previous_salary = @developer.salary
     @developer.salary = previous_salary + 10000
     @developer.touch
@@ -53,8 +51,6 @@ def test_touching_a_record_updates_its_timestamp
   end
 
   def test_touching_a_record_with_default_scope_that_excludes_it_updates_its_timestamp
-    sleep 1.0 unless supports_datetime_with_precision? # Remove once MySQL 5.5 support is dropped.
-
     developer = @developer.becomes(DeveloperCalledJamis)
     developer.touch
 
diff --git a/activerecord/test/cases/type/date_time_test.rb b/activerecord/test/cases/type/date_time_test.rb
@@ -7,7 +7,6 @@ module ActiveRecord
   module Type
     class DateTimeTest < ActiveRecord::TestCase
       def test_datetime_seconds_precision_applied_to_timestamp
-        skip "This test is invalid if subsecond precision isn't supported" unless supports_datetime_with_precision?
         p = Task.create!(starting: ::Time.now)
         assert_equal p.starting.usec, p.reload.starting.usec
       end
diff --git a/activerecord/test/schema/mysql2_specific_schema.rb b/activerecord/test/schema/mysql2_specific_schema.rb
@@ -1,19 +1,17 @@
 # frozen_string_literal: true
 
 ActiveRecord::Schema.define do
-  if connection.supports_datetime_with_precision?
-    create_table :datetime_defaults, force: true do |t|
-      t.datetime :modified_datetime, precision: nil, default: -> { "CURRENT_TIMESTAMP" }
-      t.datetime :precise_datetime, default: -> { "CURRENT_TIMESTAMP(6)" }
-      t.datetime :updated_datetime, default: -> { "CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6)" }
-    end
+  create_table :datetime_defaults, force: true do |t|
+    t.datetime :modified_datetime, precision: nil, default: -> { "CURRENT_TIMESTAMP" }
+    t.datetime :precise_datetime, default: -> { "CURRENT_TIMESTAMP(6)" }
+    t.datetime :updated_datetime, default: -> { "CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6)" }
+  end
 
-    create_table :timestamp_defaults, force: true do |t|
-      t.timestamp :nullable_timestamp
-      t.timestamp :modified_timestamp, precision: nil, default: -> { "CURRENT_TIMESTAMP" }
-      t.timestamp :precise_timestamp, precision: 6, default: -> { "CURRENT_TIMESTAMP(6)" }
-      t.timestamp :updated_timestamp, precision: 6, default: -> { "CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6)" }
-    end
+  create_table :timestamp_defaults, force: true do |t|
+    t.timestamp :nullable_timestamp
+    t.timestamp :modified_timestamp, precision: nil, default: -> { "CURRENT_TIMESTAMP" }
+    t.timestamp :precise_timestamp, precision: 6, default: -> { "CURRENT_TIMESTAMP(6)" }
+    t.timestamp :updated_timestamp, precision: 6, default: -> { "CURRENT_TIMESTAMP(6) ON UPDATE CURRENT_TIMESTAMP(6)" }
   end
 
   create_table :defaults, force: true do |t|
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
@@ -148,13 +148,8 @@
     t.index :isbn, where: "published_on IS NOT NULL", unique: true
     t.index "(lower(external_id))", unique: true if supports_expression_index?
 
-    if supports_datetime_with_precision?
-      t.datetime :created_at, precision: 6
-      t.datetime :updated_at, precision: 6
-    else
-      t.datetime :created_at
-      t.datetime :updated_at
-    end
+    t.datetime :created_at
+    t.datetime :updated_at
     t.date :updated_on
   end
 
@@ -541,17 +536,10 @@
     t.integer  :salary, default: 70000
     t.references :firm, index: false
     t.integer :mentor_id
-    if supports_datetime_with_precision?
-      t.datetime :legacy_created_at, precision: 6
-      t.datetime :legacy_updated_at, precision: 6
-      t.datetime :legacy_created_on, precision: 6
-      t.datetime :legacy_updated_on, precision: 6
-    else
-      t.datetime :legacy_created_at
-      t.datetime :legacy_updated_at
-      t.datetime :legacy_created_on
-      t.datetime :legacy_updated_on
-    end
+    t.datetime :legacy_created_at
+    t.datetime :legacy_updated_at
+    t.datetime :legacy_created_on
+    t.datetime :legacy_updated_on
   end
 
   create_table :developers_projects, force: true, id: false do |t|
@@ -685,11 +673,7 @@
 
   create_table :invoices, force: true do |t|
     t.integer :balance
-    if supports_datetime_with_precision?
-      t.datetime :updated_at, precision: 6
-    else
-      t.datetime :updated_at
-    end
+    t.datetime :updated_at
   end
 
   create_table :iris, force: true do |t|
@@ -882,11 +866,7 @@
 
   create_table :owners, primary_key: :owner_id, force: true do |t|
     t.string :name
-    if supports_datetime_with_precision?
-      t.column :updated_at, :datetime, precision: 6
-    else
-      t.column :updated_at, :datetime
-    end
+    t.column :updated_at, :datetime
     t.column :happy_at,   :datetime
     t.string :essay_id
   end
@@ -907,30 +887,18 @@
       t.string :parrot_sti_class
       t.integer :killer_id
       t.integer :updated_count, :integer, default: 0
-      if supports_datetime_with_precision?
-        t.datetime :created_at, precision: 0
-        t.datetime :created_on, precision: 0
-        t.datetime :updated_at, precision: 0
-        t.datetime :updated_on, precision: 0
-      else
-        t.datetime :created_at
-        t.datetime :created_on
-        t.datetime :updated_at
-        t.datetime :updated_on
-      end
+      t.datetime :created_at, precision: 0
+      t.datetime :created_on, precision: 0
+      t.datetime :updated_at, precision: 0
+      t.datetime :updated_on, precision: 0
     end
 
     create_table :pirates, force: :cascade do |t|
       t.string :catchphrase
       t.integer :parrot_id
       t.integer :non_validated_parrot_id
-      if supports_datetime_with_precision?
-        t.datetime :created_on, precision: 6
-        t.datetime :updated_on, precision: 6
-      else
-        t.datetime :created_on
-        t.datetime :updated_on
-      end
+      t.datetime :created_on
+      t.datetime :updated_on
     end
 
     create_table :treasures, force: :cascade do |t|
@@ -1154,11 +1122,7 @@
   create_table :ship_parts, force: true do |t|
     t.string :name
     t.integer :ship_id
-    if supports_datetime_with_precision?
-      t.datetime :updated_at, precision: 6
-    else
-      t.datetime :updated_at
-    end
+    t.datetime :updated_at
   end
 
   create_table :squeaks, force: true do |t|
@@ -1234,11 +1198,7 @@
     t.string   :title, limit: 250
     t.string   :author_name
     t.string   :author_email_address
-    if supports_datetime_with_precision?
-      t.datetime :written_on, precision: 6
-    else
-      t.datetime :written_on
-    end
+    t.datetime :written_on
     t.time     :bonus_time
     t.date     :last_read
     t.text     :content
diff --git a/activerecord/test/schema/trilogy_specific_schema.rb b/activerecord/test/schema/trilogy_specific_schema.rb
