I get that also. I think it's because I have .zprezto installed on my Mac. I guess the decorators get rendered as -ne. My current workaround is to start a different type of shell (bash).
I use bash. Curiously, when I call a new bash in the Rstudio terminal, the -ne are no longer produced. I will play a bit with my bash settings and try to isolate the issue.
I could not isolate the problem by excluding bash scripts (~/.bash_profile, etc.). zsh seems fine. The only solution was to reinstall RStudio 2023.06.1+524.
Hypothesis: a new "echo" command somewhere with an unsupported "-n" option?
R version 4.3.1 (2023-06-16)
Platform: aarch64-apple-darwin20 (64-bit)
Running under: macOS Ventura 13.6
Matrix products: default
BLAS: /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/lib/libRlapack.dylib; LAPACK version 3.11.0
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
time zone: America/Chicago
tzcode source: internal
attached base packages:
[1] stats graphics grDevices utils datasets methods base