Support for SCRIPT FLUSH with SYNC/ASYNC (#1567)

Part of #1546

redis/commands.py

@@ -2786,9 +2786,17 @@ def script_exists(self, *args):
         """
         return self.execute_command('SCRIPT EXISTS', *args)
 
-    def script_flush(self):
-        "Flush all scripts from the script cache"
-        return self.execute_command('SCRIPT FLUSH')
+    def script_flush(self, sync_type="SYNC"):
+        """Flush all scripts from the script cache.
+        ``sync_type`` is by default SYNC (synchronous) but it can also be
+                      ASYNC.
+        See: https://redis.io/commands/script-flush
+        """
+        if sync_type not in ["SYNC", "ASYNC"]:
+            raise DataError("SCRIPT FLUSH defaults to SYNC or"
+                            "accepts SYNC/ASYNC")
+        pieces = [sync_type]
+        return self.execute_command('SCRIPT FLUSH', *pieces)
 
     def script_kill(self):
         "Kill the currently executing Lua script"

tests/test_scripting.py

@@ -30,6 +30,24 @@ def test_eval(self, r):
         # 2 * 3 == 6
         assert r.eval(multiply_script, 1, 'a', 3) == 6
 
+    def test_script_flush(self, r):
+        r.set('a', 2)
+        r.script_load(multiply_script)
+        r.script_flush('ASYNC')
+
+        r.set('a', 2)
+        r.script_load(multiply_script)
+        r.script_flush('SYNC')
+
+        r.set('a', 2)
+        r.script_load(multiply_script)
+        r.script_flush()
+
+        with pytest.raises(exceptions.DataError):
+            r.set('a', 2)
+            r.script_load(multiply_script)
+            r.script_flush("NOTREAL")
+
     def test_evalsha(self, r):
         r.set('a', 2)
         sha = r.script_load(multiply_script)