CMakePresets.json : include

I am writing CMakePresets.json for a project which has hundreds of executables.
(It is a test suite for C++, but that should not be too important.)
The problem is that I get the following error.

CMake Error: Could not read presets from <project-dir>: Duplicate presets

There are many presets, not hundreds but still quite a few.
Is there a way to get a more detailed message, possibly telling me the names of the duplicates?

I am aware of the configurationPresets:debug and its friends but they only seem to work after the CMakePresets.json has been successfully processed.

The latest version in the master branch has greatly improved the error messages.

CMake Error: Could not read presets from C:/Users/me/proj:
Duplicate preset: "cb-foo"