iotests: teach FilePath to produce multiple paths

Use "FilePaths" instead of "FilePath" to request multiple files be
cleaned up after we leave that object's scope.

This is not crucial; but it saves a little typing.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-16-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

tests/qemu-iotests/iotests.py

@@ -358,31 +358,45 @@ class Timeout:
     def timeout(self, signum, frame):
         raise Exception(self.errmsg)
 
+def file_pattern(name):
+    return "{0}-{1}".format(os.getpid(), name)
 
-class FilePath(object):
-    '''An auto-generated filename that cleans itself up.
+class FilePaths(object):
+    """
+    FilePaths is an auto-generated filename that cleans itself up.
 
     Use this context manager to generate filenames and ensure that the file
     gets deleted::
 
-        with TestFilePath('test.img') as img_path:
+        with FilePaths(['test.img']) as img_path:
             qemu_img('create', img_path, '1G')
         # migration_sock_path is automatically deleted
-    '''
-    def __init__(self, name):
-        filename = '{0}-{1}'.format(os.getpid(), name)
-        self.path = os.path.join(test_dir, filename)
+    """
+    def __init__(self, names):
+        self.paths = []
+        for name in names:
+            self.paths.append(os.path.join(test_dir, file_pattern(name)))
 
     def __enter__(self):
-        return self.path
+        return self.paths
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         try:
-            os.remove(self.path)
+            for path in self.paths:
+                os.remove(path)
         except OSError:
             pass
         return False
 
+class FilePath(FilePaths):
+    """
+    FilePath is a specialization of FilePaths that takes a single filename.
+    """
+    def __init__(self, name):
+        super(FilePath, self).__init__([name])
+
+    def __enter__(self):
+        return self.paths[0]
 
 def file_path_remover():
     for path in reversed(file_path_remover.paths):
@@ -407,7 +421,7 @@ def file_path(*names):
 
     paths = []
     for name in names:
-        filename = '{0}-{1}'.format(os.getpid(), name)
+        filename = file_pattern(name)
         path = os.path.join(test_dir, filename)
         file_path_remover.paths.append(path)
         paths.append(path)