VS_DEBUGGER_ENVIRONMENT should have an INTERFACE_ variant for usage requirements (#20044) · Issues · CMake / CMake

VS_DEBUGGER_ENVIRONMENT should have an INTERFACE_ variant for usage requirements

As of CMake 3.13 I can build an executable which uses Qt5 and be able to debug it in Visual Studio like this:

cmake_minimum_required(VERSION 3.13)

project(cmaketest)

find_package(Qt5Widgets REQUIRED)

add_executable(mn main.cpp)
target_link_libraries(mn PRIVATE Qt5::Widgets)
set(targetPath
    "%PATH%;$<TARGET_FILE_DIR:Qt5::Widgets>;${otherPaths}")
set(targetEnvSep "\n")
set_property(TARGET mn PROPERTY
    VS_DEBUGGER_ENVIRONMENT "PATH=${targetPath}${targetEnvSep}QT_PLUGIN_PATH=/path/to/Qt/plugins"
)

The VS_DEBUGGER_ENVIRONMENT is useful, but it is not convenient to use in a large project because the feature lacks transitive usage requirements.

The Qt5 imported targets (and any targets) should be able to provide some expression of a usage requirement for this feature. CMake should consume the INTERFACE property and apply it to executables.

A possible design is for INTERFACE_VS_DEBUGGER_ENVIRONMENT_<ENVVAR> target properties to be populated and for CMake to aggregate them as needed. Two dependencies should be able to set different INTERFACE_VS_DEBUGGER_ENVIRONMENT_PATH content and have that combined into a single PATH setting in the VS_DEBUGGER_ENVIRONMENT content. Qt needs to be able to set QT_PLUGIN_PATH, and other dependencies might have similar requirements.

As of CMake 3.13 I can build an executable which uses Qt5 and be able to debug it in Visual Studio like this:

```
cmake_minimum_required(VERSION 3.13)

project(cmaketest)

find_package(Qt5Widgets REQUIRED)

add_executable(mn main.cpp)
target_link_libraries(mn PRIVATE Qt5::Widgets)
set(targetPath
    "%PATH%;$<TARGET_FILE_DIR:Qt5::Widgets>;${otherPaths}")
set(targetEnvSep "\n")
set_property(TARGET mn PROPERTY
    VS_DEBUGGER_ENVIRONMENT "PATH=${targetPath}${targetEnvSep}QT_PLUGIN_PATH=/path/to/Qt/plugins"
)
```

The `VS_DEBUGGER_ENVIRONMENT` is useful, but it is not convenient to use in a large project because the feature lacks transitive usage requirements.

The Qt5 imported targets (and any targets) should be able to provide some expression of a usage requirement for this feature. CMake should consume the INTERFACE property and apply it to executables.

A possible design is for `INTERFACE_VS_DEBUGGER_ENVIRONMENT_<ENVVAR>` target properties to be populated and for CMake to aggregate them as needed. Two dependencies should be able to set different `INTERFACE_VS_DEBUGGER_ENVIRONMENT_PATH` content and have that combined into a single `PATH` setting in the `VS_DEBUGGER_ENVIRONMENT` content. Qt needs to be able to set `QT_PLUGIN_PATH`, and other dependencies might have similar requirements.

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