Need help building PySide with WebEngine

scherzo

I've been trying to build PySide with WebEngine on Windows 10 x64 with MSVC 2019 and it's not working. I'll list below step by step what I'm doing.

Building Qt6

# Clone qt5 repo, dev branch (Qt6)
git clone https://code.qt.io/qt/qt5.git
cd qt5

# Here I'm getting QtWebEngine source together with the default modules
perl init-repository --module-subset="default,qtwebengine"

# Little fix to get qlitehtml module as well
cd qttools
git submodule update --init --recursive

# Change to dev branch , update submodules (chromium) and edit .qmake.conf to change Qt version from 6.0.2 to 6.2.0 just like with all other modules
cd ..\qtwebengine
git checkout dev
git submodule update

# Build and install Qt6
 ..\qt5\configure.bat -prefix "path\to\Qt\6.2.0" -release -nomake examples -nomake tests
cmake --build .
cmake --install .

Building QtWebEngine

# Here I remove Python 3 from PATH and set Python 2 paths
set PATH=%PATH:C:\Program Files\Python39\Scripts\;=%
set PATH=%PATH:C:\Program Files\Python39\;=%
set PATH=%PATH%;C:\Python27
set PATH=%PATH%;C:\Python27\Scripts

# Setting PATH to gperf, bison and flex
set PATH=%PATH%;C:\Users\scherzo\Downloads\gnuwin32\bin

# Build and install QtWebEngine (takes about 4 hours because of Chromium)
path\to\Qt\6.2.0\bin\qmake.exe -- -webengine-proprietary-codecs -webengine-webrtc -webengine-printing-and-pdf
nmake
nmake install

Building PySide6

# Clone pyside-setup repo, dev branch (Qt6)
git clone https://code.qt.io/pyside/pyside-setup.git
cd pyside-setup

# Setting up virtualenv and requirements
virtualenv venv
venv\Scripts\activate
pip install -r requirements.txt
pip install numpy

# Settting MSVC 2019 x64 environment variables
call "C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Auxiliary\Build\vcvars64.bat"

# Settting path to LLVM 12.0.0
set LLVM_INSTALL_DIR=path\to\libclang
python setup.py bdist_wheel --qmake=path\to\Qt\6.2.0\bin\qmake.exe --build-type=all

During PySide6 building, I see the following message:

-- optional module Qt6WebEngineCore skipped. Looked in: Qt6WebEngineCore_DIR-NOTFOUND
CMake Warning at path/to/pyside-setup/sources/cmake_helpers/helpers.cmake:135 (find_package):
  By not providing "FindQt6WebEngine.cmake" in CMAKE_MODULE_PATH this project
  has asked CMake to find a package configuration file provided by
  "Qt6WebEngine", but CMake did not find one.

  Could not find a package configuration file provided by "Qt6WebEngine" with
  any of the following names:

    Qt6WebEngineConfig.cmake
    qt6webengine-config.cmake

  Add the installation prefix of "Qt6WebEngine" to CMAKE_PREFIX_PATH or set
  "Qt6WebEngine_DIR" to a directory containing one of the above files.  If
  "Qt6WebEngine" provides a separate development package or SDK, be sure it
  has been installed.
Call Stack (most recent call first):
  path/to/pyside-setup/sources/cmake_helpers/helpers.cmake:102 (COLLECT_MODULE_IF_FOUND)
  CMakeLists.txt:160 (remove_skipped_modules)

Everything (Qt6, QtWebEngine and PySide6) builds without any errors, however QtWebEngine bidings aren't added to PySide6. Building and installing QtWebEngine as above doesn't create cmake files (like, for example, Qt5WebEngineCoreConfig.cmake) inside path\to\Qt\6.2.0\lib\cmake as mentioned in this blog post: https://www.qt.io/blog/building-qt-webengine-against-other-qt-versions

Does anyone know what I'm doing wrong?

Phoe

For those who have landed on this page when trying to build Pyside2 with QtWebEngineWidgets (not sure for Pyside6 because it seemed to be excluded for now in it), you need to use MaintenanceTool.exe to add Qt5WebEngineWidgets module or reinstall Qt with Qt5WebEngineWidgets checked.

After that, PySide2 build will include QtWebEngineWidgets.