Update connect args for pymysql 1.0.0; aiomysql fixes

Fixed deprecation warnings that arose as a result of the release of PyMySQL
1.0, including deprecation warnings for the "db" and "passwd" parameters
now replaced with "database" and "password".

For the 1.4 version of this patch, we are also changing tox.ini
to refer to a local branch of aiomysql that fixes pymysql
compatibility issues.

Fixes: #5821
Change-Id: I93876b52b2d96b52308f22aeb4f244ac5766a82f

6 files changed, 29 insertions, 10 deletions

diff --git a/doc/build/changelog/unreleased_13/5821.rst b/doc/build/changelog/unreleased_13/5821.rst
new file mode 100644
index 000000000..a2c5d4082
--- /dev/null
+++ b/doc/build/changelog/unreleased_13/5821.rst
@@ -0,0 +1,8 @@
+.. change::
+    :tags: bug, mysql
+    :tickets: 5821
+
+    Fixed deprecation warnings that arose as a result of the release of PyMySQL
+    1.0, including deprecation warnings for the "db" and "passwd" parameters
+    now replaced with "database" and "password".
+
diff --git a/lib/sqlalchemy/dialects/mysql/aiomysql.py b/lib/sqlalchemy/dialects/mysql/aiomysql.py
index 6381027e9..f0665133f 100644
--- a/lib/sqlalchemy/dialects/mysql/aiomysql.py
+++ b/lib/sqlalchemy/dialects/mysql/aiomysql.py
@@ -264,10 +264,9 @@ class MySQLDialect_aiomysql(MySQLDialect_pymysql):
             return pool.AsyncAdaptedQueuePool
 
     def create_connect_args(self, url):
-        args, kw = super(MySQLDialect_aiomysql, self).create_connect_args(url)
-        if "passwd" in kw:
-            kw["password"] = kw.pop("passwd")
-        return args, kw
+        return super(MySQLDialect_aiomysql, self).create_connect_args(
+            url, _translate_args=dict(username="user", database="db")
+        )
 
     def is_disconnect(self, e, connection, cursor):
         if super(MySQLDialect_aiomysql, self).is_disconnect(
diff --git a/lib/sqlalchemy/dialects/mysql/mysqldb.py b/lib/sqlalchemy/dialects/mysql/mysqldb.py
index ab5a78aad..0318b5077 100644
--- a/lib/sqlalchemy/dialects/mysql/mysqldb.py
+++ b/lib/sqlalchemy/dialects/mysql/mysqldb.py
@@ -177,10 +177,13 @@ class MySQLDialect_mysqldb(MySQLDialect):
             connection, additional_tests
         )
 
-    def create_connect_args(self, url):
-        opts = url.translate_connect_args(
-            database="db", username="user", password="passwd"
-        )
+    def create_connect_args(self, url, _translate_args=None):
+        if _translate_args is None:
+            _translate_args = dict(
+                database="db", username="user", password="passwd"
+            )
+
+        opts = url.translate_connect_args(**_translate_args)
         opts.update(url.query)
 
         util.coerce_kw_type(opts, "compress", bool)
diff --git a/lib/sqlalchemy/dialects/mysql/pymysql.py b/lib/sqlalchemy/dialects/mysql/pymysql.py
index ad61c9e29..0c321f854 100644
--- a/lib/sqlalchemy/dialects/mysql/pymysql.py
+++ b/lib/sqlalchemy/dialects/mysql/pymysql.py
@@ -57,6 +57,13 @@ class MySQLDialect_pymysql(MySQLDialect_mysqldb):
     def dbapi(cls):
         return __import__("pymysql")
 
+    def create_connect_args(self, url, _translate_args=None):
+        if _translate_args is None:
+            _translate_args = dict(username="user")
+        return super(MySQLDialect_pymysql, self).create_connect_args(
+            url, _translate_args=_translate_args
+        )
+
     def is_disconnect(self, e, connection, cursor):
         if super(MySQLDialect_pymysql, self).is_disconnect(
             e, connection, cursor
diff --git a/setup.cfg b/setup.cfg
index e151769da..f7915e43b 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -65,7 +65,9 @@ postgresql_asyncpg =
     greenlet;python_version>="3"
 postgresql_psycopg2binary = psycopg2-binary
 postgresql_psycopg2cffi = psycopg2cffi
-pymysql = pymysql
+pymysql =
+    pymysql;python_version>="3"
+    pymysql<1;python_version<"3"
 aiomysql = aiomysql
 
 [egg_info]
diff --git a/tox.ini b/tox.ini
index 8c0e0b749..8f2fd9de0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -25,7 +25,7 @@ deps=pytest>=4.6.11 # this can be 6.x once we are on python 3 only
      postgresql: .[postgresql_pg8000]; python_version >= '3'
      mysql: .[mysql]
      mysql: .[pymysql]
-     mysql: .[aiomysql]; python_version >= '3'
+     mysql: git+https://github.com/sqlalchemy/aiomysql@sqlalchemy_tox; python_version >= '3'
      mysql: .[mariadb_connector]; python_version >= '3'
 
      # we should probably try to get mysql_connector back in the mix