How to merge two folders including subfolders in batch

Question

Context

I'm trying to make a batch script that can be thrown into a pre-existing folder and upgrade it. Imagine a folder that looks like this:

• domfolder
  • LICENSE
  • merge_new_stuff.bat
  • words.txt (has 6 words)
  • awesomefolder
    • garfield.png
  • upgrade_assets
    • upgradeinfo.txt
    • new_files
      • words.txt (has 7 words)
      • awesomefolder
        • odie.png
        • awesomest
          • MONKEY.txt
      • subfolder
        • subsubfolder
          • numbers.txt

The sole purpose of merge_new_stuff.bat is to take everything inside the new_files folder, and bring it into domfolder, replacing any pre-existing files like words.txt, leaving anything else alone, and getting rid of the upgrade_assets folder. So if everything goes right, the folder structure should like this after running:

• domfolder
  • LICENSE
  • merge_new_stuff.bat
  • words.txt (has 7 words)
  • awesomefolder
    • garfield.png
    • odie.png
    • awesomest
      • MONKEY.txt
  • subfolder
    • subsubfolder
      • numbers.txt

What I've Tried

First instinct is to just use a simple move command: move /y upgrade_assets\new_files\*
That upgrades words.txt, but it totally ignores the folders. Only part of what I want.
I tried a for loop to see if it'd be different somehow, same results:
for %%A in (upgrade_assets\new_files\*) do move /y %%A

Next, I tried looping through dir results alongside the basic move:
for /f "tokens=*" %%A in ('dir /b /s /a:d "upgrade_assets\new_files"') do move /y "%%A\*.*" "%~dp0%%~nxA"
This almost worked, properly moving odie.png and subfolder\subsubfolder\numbers.txt. But once it tries to move MONKEY.txt, it... decides to make a file called "awesomest" that has the contents of MONKEY.txt? So clearly, it doesn't handle going down pre-existing folders, which is definitely not helpful.

Looking around, I only found one thread that seems close to what I want. Most of the replies mention xcopy/robocopy, but I want to avoid the copy/delete method as much as possible considering the potential size of updates. And when I changed the accepted answer to fit what I'm doing, it still had issues going more than one folder deep.

for /d /r upgrade_assets\new_files %%A in (*) do (
    if exist "%~dp0%%~nA" ( 
        dir "%%A" | find "0 File(s)" > NUL
        if errorlevel 1 move /y "%%A\*.*" "%~dp0%%~nA"
    ) else (
        move /y "%%A" %~dp0
    )
)

I'm pretty sure the issue is centered around %~dp0%%~nA , I need a way to have it read more than just the folder the file being copied is in, which is all %%~nA shows.

Preferably, the solution should be completely independent of what actual files are in the folder, so it can be used with any update. If I need external tools, I would like them to be free/libre software if possible. I'm running Windows 10, but I know this script will be run by people using Windows 7.

Answer 1

Quite frankly this will do exactly what you want.

robocopy .\upgrade_assets\new_files\ . /E /MOVE

It will create the directories and files as well as delete from source once done.