Output: {file_path: [(line_a_start, line_a_end), (line_b_start, line_b_end)]}

        Lines ranges are sorted and not overlapping

def get_user_modified_lines(self):
        """
        Output: {file_path: [(line_a_start, line_a_end), (line_b_start, line_b_end)]}

        Lines ranges are sorted and not overlapping
        """
        # I assume that git diff:
        # - doesn't mix diffs from different files,
        # - diffs are not overlapping
        # - diffs are sorted based on line numbers
        output = {}

        FILE_NAME_RE = r'^\+\+\+ (.+)$'
        CHANGED_LINES_RE = r'^@@ -[0-9,]+ \+([0-9]+)(?:,([0-9]+))? @@'
        current_file_name = None

        for line in self.git_wrapper.get_min_diff(self.remote_sha1, self.local_sha1).split('\n'):
            file_name_match = re.match(FILE_NAME_RE, line)
            if file_name_match:
                current_file_name, = file_name_match.groups()
                output[current_file_name] = []
                continue

            line_number_match = re.match(CHANGED_LINES_RE, line)
            if line_number_match:
                assert current_file_name
                if current_file_name == '/dev/null':
                    continue
                line_start, diff_len = line_number_match.groups()
                line_start, diff_len = int(line_start), int(diff_len or 0)
                output[current_file_name].append(LinesRange(line_start, line_start + diff_len))
                continue

        return output