Disable S3 Express support for s3 mb command (#8824)

.changes/next-release/bugfix-s3-90647.json

@@ -0,0 +1,5 @@
+{
+  "type": "bugfix",
+  "category": "``s3``",
+  "description": "Disable usage of mb command with S3 Express directory buckets."
+}

awscli/customizations/s3/subcommands.py

@@ -801,6 +801,9 @@ def _run_main(self, parsed_args, parsed_globals):
             raise TypeError("%s\nError: Invalid argument type" % self.USAGE)
         bucket, _ = split_s3_bucket_key(parsed_args.path)
 
+        if is_s3express_bucket(bucket):
+            raise ValueError("Cannot use mb command with a directory bucket.")
+
         bucket_config = {'LocationConstraint': self.client.meta.region_name}
         params = {'Bucket': bucket}
         if self.client.meta.region_name != 'us-east-1':

tests/functional/s3/test_mb_command.py

@@ -45,3 +45,8 @@ def test_location_constraint_not_added_on_us_east_1(self):
     def test_nonzero_exit_if_invalid_path_provided(self):
         command = self.prefix + 'bucket'
         self.run_cmd(command, expected_rc=255)
+
+    def test_incompatible_with_express_directory_bucket(self):
+        command = self.prefix + 's3://bucket--usw2-az1--x-s3/'
+        stderr = self.run_cmd(command, expected_rc=255)[1]
+        self.assertIn('Cannot use mb command with a directory bucket.', stderr)