Add export_component_deps_pkgconfig example

Find use_component_deps_c with pkg-config and ensure that
it properly links to the component_deps components.

(not yet working)

Signed-off-by: Steve Peters <scpeters@openrobotics.org>

examples/CMakeLists.txt

@@ -26,6 +26,7 @@ if (NOT CMAKE_GENERATOR MATCHES "Visual Studio")
     use_component_deps_b
     use_component_deps_c
     export_component_deps_cmake
+    export_component_deps_pkgconfig
   )
 endif()
 
@@ -56,6 +57,8 @@ foreach(example ${example_directories})
     set(example_tarball_name gz-component_deps-0.1.0.tar.bz2)
   elseif (${example} STREQUAL "export_component_deps_cmake")
     set(example_tarball_name gz-export_component_deps_cmake-0.1.0.tar.bz2)
+  elseif (${example} STREQUAL "export_component_deps_pkgconfig")
+    set(example_tarball_name gz-export_component_deps_pkgconfig-0.1.0.tar.bz2)
   elseif (${example} STREQUAL "use_component_deps_a")
     set(example_tarball_name gz-use_component_deps_a-0.1.0.tar.bz2)
   elseif (${example} STREQUAL "use_component_deps_b")
@@ -181,6 +184,9 @@ foreach (build_type ${build_types})
   if (TARGET export_component_deps_cmake_${build_type})
     add_dependencies(export_component_deps_cmake_${build_type} use_component_deps_c_${build_type})
   endif()
+  if (TARGET export_component_deps_pkgconfig_${build_type})
+    add_dependencies(export_component_deps_pkgconfig_${build_type} use_component_deps_c_${build_type})
+  endif()
 endforeach()
 
 # test that core_child pkg-config file requires core_nodep

examples/export_component_deps_pkgconfig/CMakeLists.txt

@@ -0,0 +1,9 @@
+cmake_minimum_required(VERSION 3.22.1 FATAL_ERROR)
+project(gz-export_component_deps_pkgconfig VERSION 0.1.0)
+find_package(gz-cmake4 REQUIRED)
+gz_configure_project()
+include(GzPkgConfig)
+gz_pkg_check_modules(gz-use_component_deps_c "gz-use_component_deps_c")
+gz_configure_build(QUIT_IF_BUILD_ERRORS)
+gz_create_packages()
+gz_create_docs()

examples/export_component_deps_pkgconfig/src/AlmostEmpty.cc

@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2018 Open Source Robotics Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+*/
+
+#include <gz/use_component_deps_c/AlmostEmpty.hh>

examples/export_component_deps_pkgconfig/src/CMakeLists.txt

@@ -0,0 +1,6 @@
+gz_get_libsources_and_unittests(sources gtest_sources)
+gz_create_core_library(SOURCES ${sources} CXX_STANDARD 11)
+target_link_libraries(${PROJECT_LIBRARY_TARGET_NAME}
+  PUBLIC
+    gz-use_component_deps_c::gz-use_component_deps_c)
+gz_build_tests(TYPE UNIT SOURCES ${gtest_sources})