qemu-iotests: Support varargs syntax in FilePaths

Accept variable number of names instead of a sequence:

    with FilePaths("a", "b", "c") as (a, b, c):

The disadvantage is that base_dir must be used as kwarg:

    with FilePaths("a", "b", base_dir=soc_dir) as (sock1, sock2):

But this is more clear and calling optional argument as positional
arguments is bad idea anyway.

Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200828232152.205833-4-nsoffer@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

tests/qemu-iotests/194

@@ -26,8 +26,8 @@ iotests.script_initialize(supported_fmts=['qcow2', 'qed', 'raw'],
 
 with iotests.FilePath('source.img') as source_img_path, \
      iotests.FilePath('dest.img') as dest_img_path, \
-     iotests.FilePaths(['migration.sock', 'nbd.sock'], iotests.sock_dir) as \
-         [migration_sock_path, nbd_sock_path], \
+     iotests.FilePaths('migration.sock', 'nbd.sock', base_dir=iotests.sock_dir) \
+        as (migration_sock_path, nbd_sock_path), \
      iotests.VM('source') as source_vm, \
      iotests.VM('dest') as dest_vm:
 

tests/qemu-iotests/257

@@ -275,10 +275,9 @@ def test_bitmap_sync(bsync_mode, msync_mode='bitmap', failure=None):
                         an incomplete backup. Testing limitations prevent
                         testing competing writes.
     """
-    with iotests.FilePaths(['img', 'bsync1', 'bsync2',
-                            'fbackup0', 'fbackup1', 'fbackup2']) as \
-                            (img_path, bsync1, bsync2,
-                             fbackup0, fbackup1, fbackup2), \
+    with iotests.FilePaths(
+            'img', 'bsync1', 'bsync2', 'fbackup0', 'fbackup1', 'fbackup2') as \
+            (img_path, bsync1, bsync2, fbackup0, fbackup1, fbackup2), \
          iotests.VM() as vm:
 
         mode = "Mode {:s}; Bitmap Sync {:s}".format(msync_mode, bsync_mode)
@@ -441,8 +440,7 @@ def test_backup_api():
     """
     Test malformed and prohibited invocations of the backup API.
     """
-    with iotests.FilePaths(['img', 'bsync1']) as \
-         (img_path, backup_path), \
+    with iotests.FilePaths('img', 'bsync1') as (img_path, backup_path), \
          iotests.VM() as vm:
 
         log("\n=== API failure tests ===\n")

tests/qemu-iotests/iotests.py

@@ -455,7 +455,7 @@ class FilePaths:
 
     Example usage:
 
-        with FilePaths(['a.img', 'b.img']) as (img_a, img_b):
+        with FilePaths('a.img', 'b.img') as (img_a, img_b):
             # Use img_a and img_b here...
 
         # a.img and b.img are automatically removed here.
@@ -463,10 +463,10 @@ class FilePaths:
     By default images are created in iotests.test_dir. To create sockets use
     iotests.sock_dir:
 
-       with FilePaths(['a.sock'], base_dir=iotests.sock_dir) as (sock,):
+       with FilePaths('a.sock', base_dir=iotests.sock_dir) as (sock,):
 
     """
-    def __init__(self, names, base_dir=test_dir):
+    def __init__(self, *names, base_dir=test_dir):
         self.paths = []
         for name in names:
             self.paths.append(os.path.join(base_dir, file_pattern(name)))
@@ -487,7 +487,7 @@ class FilePath(FilePaths):
     FilePath is a specialization of FilePaths that takes a single filename.
     """
     def __init__(self, name, base_dir=test_dir):
-        super(FilePath, self).__init__([name], base_dir)
+        super(FilePath, self).__init__(name, base_dir=base_dir)
 
     def __enter__(self):
         return self.paths[0]