private ApplicationFile writeFile(byte[] input) {
            if (content != null) throw new UnsupportedOperationException("Not implemented for mock file content");
            uncheck(() -> Files.write(file.toPath(), input));
            return this;
        }
The content of this file, or null to read it from the file system.
config-model/src/main/java/com/yahoo/config/model/test/MockApplicationPackage.java