cmake completion for --find-package lacks required -D arguments

The current cmake completion does not suggest the -D arguments that are required when running --find-package. See also stackoverflow.

Essentially, when one uses --find-package, also -DNAME must be set. Otherwise cmake complains:

CMake Error at /usr/share/cmake-3.12/Modules/CMakeFindPackageMode.cmake:33 (message):
  Name of the package to be searched not specified.  Set the CMake variable
  NAME, e.g.  -DNAME=JPEG .

Further down the line one gets

CMake Error at /usr/share/cmake-3.12/Modules/CMakeFindPackageMode.cmake:37 (message):
  COMPILER_ID argument not specified.  In doubt, use GNU.

then

CMake Error at /usr/share/cmake-3.12/Modules/CMakeFindPackageMode.cmake:41 (message):
  LANGUAGE argument not specified.  Use C, CXX or Fortran.

and eventually

CMake Error at /usr/share/cmake-3.12/Modules/CMakeFindPackageMode.cmake:45 (message):
  MODE argument not specified.  Use either EXIST, COMPILE or LINK.

I.e. --find-package implies that -DNAME=, -DLANGUAGE=, -DCOMPILER_ID= and -DMODE= are provided. The possible values are spelled out in the error messages above.

I don't see how to add that myself to the current completion (given time constraints and priorities).