Fix mysql2 gem types (#764)

- Add `Mysql2::Client#affected_rows`
- Full support `Mysql2::row_value_type`
  - Add `BigDecimal`, `Float`, `Time`, `Date`
- Add `Mysql2::Result#size` and `Mysql2::Result#count`

gems/mysql2/0.5/_test/client.rb

@@ -0,0 +1,8 @@
+client = Mysql2::Client.new
+
+client.query("UPDATE users SET age = age + 1 WHERE name = 'John'")
+if client.affected_rows == 0
+  puts "No rows were updated"
+else
+  puts "Updated #{client.affected_rows} rows"
+end

gems/mysql2/0.5/_test/result.rb

@@ -0,0 +1,3 @@
+client = Mysql2::Client.new
+result = client.query("SELECT * FROM users WHERE age > 10")
+result.size

gems/mysql2/0.5/_test/row_value_type.rb

@@ -0,0 +1,82 @@
+client = Mysql2::Client.new
+
+client.query %[
+  CREATE TABLE IF NOT EXISTS mysql2_test (
+    id MEDIUMINT NOT NULL AUTO_INCREMENT,
+    null_test VARCHAR(10),
+    bit_test BIT(64),
+    single_bit_test BIT(1),
+    tiny_int_test TINYINT,
+    bool_cast_test TINYINT(1),
+    small_int_test SMALLINT,
+    medium_int_test MEDIUMINT,
+    int_test INT,
+    big_int_test BIGINT,
+    float_test FLOAT(10,3),
+    float_zero_test FLOAT(10,3),
+    double_test DOUBLE(10,3),
+    decimal_test DECIMAL(10,3),
+    decimal_zero_test DECIMAL(10,3),
+    date_test DATE,
+    date_time_test DATETIME,
+    timestamp_test TIMESTAMP,
+    time_test TIME,
+    year_test YEAR(4),
+    char_test CHAR(10),
+    varchar_test VARCHAR(10),
+    binary_test BINARY(10),
+    varbinary_test VARBINARY(10),
+    tiny_blob_test TINYBLOB,
+    tiny_text_test TINYTEXT,
+    blob_test BLOB,
+    text_test TEXT,
+    medium_blob_test MEDIUMBLOB,
+    medium_text_test MEDIUMTEXT,
+    long_blob_test LONGBLOB,
+    long_text_test LONGTEXT,
+    enum_test ENUM('val1', 'val2'),
+    set_test SET('val1', 'val2'),
+    PRIMARY KEY (id)
+  )
+]
+client.query "DELETE FROM mysql2_test;"
+client.query %[
+  INSERT INTO mysql2_test (
+    null_test, bit_test, single_bit_test, tiny_int_test, bool_cast_test, small_int_test, medium_int_test, int_test, big_int_test,
+    float_test, float_zero_test, double_test, decimal_test, decimal_zero_test, date_test, date_time_test, timestamp_test, time_test,
+    year_test, char_test, varchar_test, binary_test, varbinary_test, tiny_blob_test,
+    tiny_text_test, blob_test, text_test, medium_blob_test, medium_text_test,
+    long_blob_test, long_text_test, enum_test, set_test
+  )
+
+  VALUES (
+    NULL, b'101', b'1', 1, 1, 10, 10, 10, 10,
+    10.3, 0, 10.3, 10.3, 0, '2010-4-4', '2010-4-4 11:44:00', '2010-4-4 11:44:00', '11:44:00',
+    2009, "test", "test", "test", "test", "test",
+    "test", "test", "test", "test", "test",
+    "test", "test", 'val1', 'val1,val2'
+  )
+]
+
+test_result = client.query("SELECT * FROM mysql2_test ORDER BY id DESC LIMIT 1").first || raise
+
+# NULL => nil
+test_result['null_test'] #: nil
+# BIT(64) => String
+test_result['bit_test'] #: String
+# TINYINT => Integer
+test_result['tiny_int_test'] #: Integer
+# INT => Integer
+test_result['int_test'] #: Integer
+# DECIMAL => BigDecimal
+test_result['decimal_test'] #: BigDecimal
+# FLOAT => Float
+test_result['float_test'] #: Float
+# DATETIME => Time
+test_result['date_time_test'] #: Time
+# TIMESTAMP => Time
+test_result['timestamp_test'] #: Time
+# DATE => Date
+test_result['date_test'] #: Date
+# ENUM => String
+test_result['enum_test'] #: String

gems/mysql2/0.5/client.rbs

@@ -44,6 +44,8 @@ module Mysql2
 
     def last_id: () -> Integer
 
+    def affected_rows: () -> Integer
+
     private
 
     def self.local_offset: () -> untyped

gems/mysql2/0.5/manifest.yaml

@@ -0,0 +1,8 @@
+# manifest.yaml describes dependencies which do not appear in the gemspec.
+# If this gem includes such dependencies, comment-out the following lines and
+# declare the dependencies.
+# If all dependencies appear in the gemspec, you should remove this file.
+#
+dependencies:
+  - name: bigdecimal
+  - name: date

gems/mysql2/0.5/result.rbs

@@ -1,12 +1,20 @@
 module Mysql2
-  type row_value_type = String | Integer | nil
+  type row_value_type = String | Integer | BigDecimal | Float | Time | Date | nil
 
   class ResultAsHash
     attr_reader server_flags: untyped
 
-    include Enumerable[Hash[Symbol, row_value_type]]
+    # NOTE:
+    #   The type of key is controlled by `symbolize_keys` option of `Mysql2::Client.new`.
+    #   It can be expressed using a type argument such as `Client[ResultType]`,
+    #   but since the state becomes complicated. So `String | Symbol` is allowed.
+    type key_type = String | Symbol
 
-    def each: () { (Hash[Symbol, row_value_type]) -> void } -> void
+    include Enumerable[Hash[key_type, row_value_type]]
+
+    def each: () { (Hash[key_type, row_value_type]) -> void } -> void
+    def count: () -> Integer
+    alias size count
   end
 
   class ResultAsArray
@@ -15,5 +23,7 @@ module Mysql2
     include Enumerable[Array[row_value_type]]
 
     def each: () { (Array[row_value_type]) -> void } -> void
+    def count: () -> Integer
+    alias size count
   end
 end