orm: redesign orm (re-write it in V) (#10353)

vlib/mysql/mysql_orm_test.v

@@ -0,0 +1,77 @@
+import orm
+import mysql
+
+fn test_mysql_orm() {
+	mut mdb := mysql.Connection{
+		host: 'localhost'
+		port: 3306
+		username: 'root'
+		password: ''
+		dbname: 'mysql'
+	}
+	mdb.connect() or { panic(err) }
+	db := orm.Connection(mdb)
+	db.create('Test', [
+		orm.TableField{
+			name: 'id'
+			typ: 7
+			attrs: [
+				StructAttribute{
+					name: 'primary'
+				},
+				StructAttribute{
+					name: 'sql'
+					has_arg: true
+					kind: .plain
+					arg: 'serial'
+				},
+			]
+		},
+		orm.TableField{
+			name: 'name'
+			typ: 18
+			attrs: []
+		},
+		orm.TableField{
+			name: 'age'
+			typ: 7
+		},
+	]) or { panic(err) }
+
+	db.insert('Test', orm.QueryData{
+		fields: ['name', 'age']
+		data: [orm.string_to_primitive('Louis'), orm.int_to_primitive(101)]
+	}) or { panic(err) }
+
+	res := db.@select(orm.SelectConfig{
+		table: 'Test'
+		has_where: true
+		fields: ['id', 'name', 'age']
+		types: [7, 18, 8]
+	}, orm.QueryData{}, orm.QueryData{
+		fields: ['name', 'age']
+		data: [orm.Primitive('Louis'), i64(101)]
+		types: [18, 8]
+		is_and: [true, true]
+		kinds: [.eq, .eq]
+	}) or { panic(err) }
+
+	id := res[0][0]
+	name := res[0][1]
+	age := res[0][2]
+
+	assert id is int
+	if id is int {
+		assert id == 1
+	}
+
+	assert name is string
+	if name is string {
+		assert name == 'Louis'
+	}
+
+	assert age is i64
+	if age is i64 {
+		assert age == 101
+	}
+}