[BUG] [cpp-qt] Unable to run cmake and use Qt5 anymore

[xconverge]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

I am unable to run the generator after updating to a newer version (7.2.0) and using Qt5. I didn't change anything about my Qt installation, just the openapi-generator version, and ran into failures. (I also upgraded CMake just to be sure).

I set CMAKE_PREFIX_PATH before running like this (to set my Qt version):

export CMAKE_PREFIX_PATH=C:\\Qt\\5.15.16\\msvc2019_64\\lib\\cmake
cmake  ../src/client/

I get this:

-- Building for: Visual Studio 17 2022
CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required):
  Compatibility with CMake < 3.5 will be removed from a future version of
  CMake.

  Update the VERSION argument <min> value or use a ...<max> suffix to tell
  CMake that the project does not need compatibility with older versions.


-- Selecting Windows SDK version 10.0.20348.0 to target Windows 10.0.22631.
-- The C compiler identification is MSVC 19.38.33134.0
-- The CXX compiler identification is MSVC 19.38.33134.0
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.38.33130/bin/Hostx64/x64/cl.exe - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.38.33130/bin/Hostx64/x64/cl.exe - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
CMake Warning (dev) at CMakeLists.txt:5 (find_package):
  Policy CMP0084 is not set: The FindQt module does not exist for
  find_package().  Run "cmake --help-policy CMP0084" for policy details.  Use
  the cmake_policy command to set the policy and suppress this warning.

This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Error at C:/Program Files/CMake/share/cmake-3.28/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
  Could NOT find Qt3 (missing: QT_QT_LIBRARY QT_INCLUDE_DIR
  QT_MOC_EXECUTABLE)
Call Stack (most recent call first):
  C:/Program Files/CMake/share/cmake-3.28/Modules/FindPackageHandleStandardArgs.cmake:600 (_FPHSA_FAILURE_MESSAGE)
  C:/Program Files/CMake/share/cmake-3.28/Modules/FindQt3.cmake:213 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  C:/Program Files/CMake/share/cmake-3.28/Modules/FindQt.cmake:160 (include)
  CMakeLists.txt:5 (find_package)


-- Configuring incomplete, errors occurred!

If I add find_package(QT NAMES Qt6 Qt5 REQUIRED COMPONENTS Core Network Gui) back in, all works fine and generates

@MartinDelille do you remember why in #14968 this line was removed?

[MartinDelille]

This is indeed an error that passed review without anyone noticing it! Would you be able to submit a PR to fix it ? You'll need to update both the CMakeLists.txt.mustache and CMakeLists.txt files.

[xconverge]

This allowed me to build the client but I ran into linker errors when I went to use it, is there more to that file/changeset that looks like an error to you? or just the 1 line missing?

I probably wont be able to make a PR as I am phasing away from using this client but I will see if I have my dev environment setup still later in case I find some time