<NME> screenshot.py
<BEF> # @license
# Copyright 2017 Google Inc.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from __future__ import absolute_import

import os


class ScreenshotSaver(object):
    def __init__(self, viewer, directory):
        self.viewer = viewer
        self.directory = directory

        if not os.path.exists(directory):
            os.makedirs(directory)

        self.index = 0

    def capture(self):
        s = self.viewer.screenshot()
        index = self.index
        path = os.path.join(self.directory, '%07d.png' % index)
        with open(path, 'wb') as f:
            f.write(s.screenshot.image)
        self.index += 1
        index, path = self.get_next_path(index)
        with open(path, 'wb') as f:
            f.write(s.screenshot.image)
        if increment_index:
            self.index += 1
        return index, path

<MSG> feat(python): factor out logic for computing output path from capture method

<DFF> @@ -27,10 +27,14 @@ class ScreenshotSaver(object):
 
         self.index = 0
 
-    def capture(self):
-        s = self.viewer.screenshot()
+    def get_next_path(self):
         index = self.index
         path = os.path.join(self.directory, '%07d.png' % index)
+        return index, path
+
+    def capture(self):
+        s = self.viewer.screenshot()
+        index, path = self.get_next_path()
         with open(path, 'wb') as f:
             f.write(s.screenshot.image)
         self.index += 1

feat(python): factor out logic for computing output path from capture method