Ignore svn:externals definition in some clients?

Hi all,

I have a large SVN repo containing various libs. Some of those are
versioned as files within our own repo, some only referenced using
svn:externals to be available in a local file tree always at the same
place for all users. Some of those externals refer to native SVN
repos, some use the GitHub SVN bridge.

One of those GitHub repos is special, because it's only a read-only
mirror of a native Git repo hosted elsewhere. So I reference that
read-only mirror using the SVN bridge of GitHub to be able to provide
it's content to my colleagues, while I have write access to the native
Git repo.

The problem is that I mostly work in the SVN tree at that special lib
as well for various setup reasons, but can't commit using the SVN
bridge of GitHub, because this project is read-only. So after things
work I copy them manually to the Git clone and commit them there,
update using SVN afterwards etc.

That's not a good solution, so I decided to simply replace the working
copy created for the svn:external of the read-only GitHub mirror with
a native Git clone. The dir structure and everything is the same of
course, it's only SVN vs. Git.

This works in general, but whenever I update my SVN working copy I get
an error message from the SVN client related the one svn:external I
replaced with a Git clone. That error makes sense of course, because I
broke things, but in this special case I would like to suppress the
error somehow because I simply don't care.

So, is there some way for a SVN client to be configured in a way that
some svn:externals of some paths are ignored or something like that?

I don't want to create some fancy scripts or such, in the end I could
live with the error and simply ignore it myself. I'm talking about the
"src" folder in the following example:

> C:\[...]\0.11.0-SNAPSHOT>dir
> Datenträger in Laufwerk C: ist System
> Volumeseriennummer: 266B-2863
>
> Verzeichnis von C:\[...]\0.11.0-SNAPSHOT
>
> 06.07.2017 09:25 <DIR> .
> 06.07.2017 09:25 <DIR> ..
> 19.04.2017 18:27 <DIR> build
> 13.10.2015 11:55 2.256 README.txt
> 06.07.2017 10:06 <DIR> src
> 02.07.2016 15:50 <DIR> web
> 1 Datei(en), 2.256 Bytes
> 5 Verzeichnis(se), 1.550.992.760.832 Bytes frei
>
> C:\[...]\0.11.0-SNAPSHOT>svn up
> Updating '.':
>
> Fetching external item into 'src':
> svn: warning: W155007: Can't obtain lock on non-directory 'C:\[...]\0.11.0-SNAPSHOT\src'.
>
>
> Fetching external item into 'web':
> External at revision 1015044.
>
> At revision 5780.
> svn: E205011: Failure occurred processing one or more externals definitions

Thanks for your input!

Mit freundlichen Grüßen,

Thorsten Schöning

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