use CLI C++ code generator with CMake, put crates in cargo workspace

.github/workflows/github-cxx-qt-tests.yml

@@ -21,6 +21,8 @@ jobs:
             # TODO: Remove PPA for Qt 5.15 when Ubuntu 22.04 is available
             # https://github.com/KDAB/cxx-qt/issues/121
             ppa: ppa:savoury1/qt-5-15
+            # FIXME: linking fails with GNU ld
+            ldflags: '-fuse-ld=lld'
             packages-extra: >-
                 qtbase5-dev
                 qtdeclarative5-dev
@@ -38,6 +40,8 @@ jobs:
             # TODO: Remove PPA for Qt 6 when Ubuntu 22.04 is available
             # https://github.com/KDAB/cxx-qt/issues/121
             ppa: ppa:daschuer/qt6-backports
+            # FIXME: linking fails with GNU ld
+            ldflags: '-fuse-ld=lld'
             packages-extra: >-
                 qt6-base-dev
                 qt6-declarative-dev
@@ -158,6 +162,7 @@ jobs:
         sudo apt-get update &&
         sudo apt-get install -y
         ninja-build
+        lld
         clang-format-12
         libssl-dev
         pkg-config
@@ -203,6 +208,7 @@ jobs:
         RUSTC_WRAPPER: sccache
         CC: ${{ matrix.cc }}
         CXX: ${{ matrix.cxx }}
+        LDFLAGS: ${{ matrix.ldflags }}
     - name: "Build"
       run: cmake --build build --config Release --parallel 2
       working-directory: ${{ matrix.workspace }}

CMakeLists.txt

@@ -22,6 +22,10 @@ else()
     option(VCPKG "Use vcpkg for dependencies" OFF)
 endif()
 
+if(WIN32)
+    set(EXE_SUFFIX ".exe")
+endif()
+
 if(VCPKG)
     # Explicitly setting QT_DEFAULT_MAJOR_VERSION can fail on systems that have both Qt6
     # and Qt5 installed, so only set it automatically when using vcpkg.
@@ -40,12 +44,10 @@ if(VCPKG)
     if(NOT DEFINED ENV{VCPKG_BINARY_SOURCES})
         if(WIN32)
             set(COMMAND_PREIFX "")
-            set(EXE_SUFFIX ".exe")
             set(SCRIPT_SUFFIX ".bat")
             set(DOTNET_RUNTIME "")
         else()
             set(COMMAND_PREFIX "./")
-            set(EXE_SUFFIX "")
             set(SCRIPT_SUFFIX ".sh")
             set(DOTNET_RUNTIME "mono")
         endif()
@@ -101,9 +103,73 @@ project(cxx_qt)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
-
 include(CompilerCaching)
 
+set(CORROSION_VERSION 0.2.1)
+find_package(Corrosion ${CORROSION_VERSION} QUIET)
+if(NOT Corrosion_FOUND)
+    message(STATUS "Corrosion not found, downloading...")
+    include(FetchContent)
+    FetchContent_Declare(
+        Corrosion
+        GIT_REPOSITORY https://github.com/corrosion-rs/corrosion.git
+        GIT_TAG v${CORROSION_VERSION}
+    )
+    FetchContent_MakeAvailable(Corrosion)
+endif()
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cxx-qt-lib")
+include(CxxQt)
+
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core Gui REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Gui REQUIRED)
+
+if(CMAKE_BUILD_TYPE STREQUAL "Release")
+    set(CARGO_BUILD_TYPE "--release")
+    set(CARGO_BUILD_TYPE_DIR "release")
+else()
+    set(CARGO_BUILD_TYPE_DIR "debug")
+endif()
+
+# FIXME: cxx's build.rs fails without this.
+# https://github.com/dtolnay/cxx/issues/1020
+if(APPLE)
+    set(ENV{SDKROOT} ${CMAKE_OSX_SYSROOT})
+endif()
+
+message(STATUS "Building C++ code generator and generating C++ library")
+set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS cxx-qt-lib)
+set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS cxx-qt-cli)
+set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS cxx-qt-gen)
+set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS cxx-qt-build)
+set(CARGO_TARGET_DIR "${CMAKE_BINARY_DIR}/cargo")
+set(CXXQT_CPP_LIB_GENERATED_DIR "${CMAKE_CURRENT_BINARY_DIR}/cxx-qt-cpplib")
+execute_process(
+    COMMAND ${CMAKE_COMMAND} -E env
+        "CARGO_TARGET_DIR=${CARGO_TARGET_DIR}"
+        "SDKROOT=${CMAKE_OSX_SYSROOT}"
+        "CXX_QT_LIB_OUT_DIR=${CXXQT_CPP_LIB_GENERATED_DIR}"
+        cargo build ${CARGO_BUILD_TYPE}
+        --manifest-path "${CMAKE_CURRENT_SOURCE_DIR}/Cargo.toml"
+        --package cxx-qt-cli
+        --package cxx-qt-lib
+)
+set(CXXQTBRIDGE_EXECUTABLE "${CARGO_TARGET_DIR}/${CARGO_BUILD_TYPE_DIR}/cxxqtbridge${EXE_SUFFIX}")
+
+add_subdirectory(${CXXQT_CPP_LIB_GENERATED_DIR})
+
+# This is extremely hacky, but such is CMake. The find_package calls
+# in the examples don't actually work because the CMake package config files
+# are not generated until install time. One would think the export() command
+# could work around this; however, it does not. The export() command does not
+# create the CxxQt{5/6}Targets.cmake file until the *end* of the configure
+# step, so find_package in the examples can't depend on the targets file
+# generated by export(). By creating this library alias target, the
+# CMakeLists.txt in the examples can actually serve as examples of how
+# downstream projects should write their CMakeLists.txt. The examples can
+# use find_package with QUIET and without REQUIRE so the find_package call
+# serves as an example but doesn't actually do anything. Because CMake.
+add_library(CxxQt${QT_VERSION_MAJOR}::cxxqt ALIAS cxxqt)
+
 # Enable extra Qt definitions for all projects
 add_compile_definitions(
     QT_NO_CAST_FROM_ASCII

Cargo.toml

@@ -0,0 +1,22 @@
+# SPDX-FileCopyrightText: 2021 Klarälvdalens Datakonsult AB, a KDAB Group company <[email protected]>
+# SPDX-FileContributor: Be Wilson <[email protected]>
+#
+# SPDX-License-Identifier: MIT OR Apache-2.0
+
+[workspace]
+members = [
+    "cxx-qt",
+    "cxx-qt-build",
+    "cxx-qt-cli",
+    "cxx-qt-gen",
+
+    "examples/demo_threading",
+    "examples/qml_extension_plugin/core",
+    "examples/qml_features",
+    "examples/qml_minimal",
+    "examples/qml_with_threaded_logic",
+
+    "tests/basic_cxx_only",
+    "tests/basic_cxx_qt",
+    "tests/qt_types_standalone",
+]

cxx-qt-build/Cargo.toml

@@ -13,13 +13,9 @@ description = "Helpers for integrating `cxx-qt` crate into a Cargo build"
 repository = "https://github.com/KDAB/cxx-qt/"
 
 [dependencies]
-clang-format = "0.1"
 cxx-gen = "0.7"
-cxx-qt-lib = { path = "../cxx-qt-lib", version = "0.3" }
 cxx-qt-gen = { path = "../cxx-qt-gen", version = "0.3" }
 proc-macro2 = "1.0"
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1.0"
 syn = { version = "1.0", features = ["extra-traits", "full", "parsing"] }
 quote = "1.0"
 convert_case = "0.4"