feat: cleanup CMake configs to work in -cpp (#1476)

Fixes: googleapis/google-cloud-cpp#3975
Fixes: googleapis/google-cloud-cpp#3974

This PR mainly adds a `cmake/GoogleCloudCppCommon.cmake` file was copied
from `-cpp`. It also removes spanner-specific CMake variable names in
favor of generic `GOOGLE_CLOUD_CPP_*` naming to match what will be used
in `-cpp`.

Author: devjgm

CMakeLists.txt

@@ -57,12 +57,12 @@ include(SelectMSVCRuntime)
 include(EnableCxxExceptions)
 
 # This should be included from the top level CMakeLists file
-set(SPANNER_CLIENT_VERSION_MAJOR 1)
-set(SPANNER_CLIENT_VERSION_MINOR 2)
-set(SPANNER_CLIENT_VERSION_PATCH 0)
-string(CONCAT SPANNER_CLIENT_VERSION "${SPANNER_CLIENT_VERSION_MAJOR}" "."
-              "${SPANNER_CLIENT_VERSION_MINOR}" "."
-              "${SPANNER_CLIENT_VERSION_PATCH}")
+set(GOOGLE_CLOUD_CPP_VERSION_MAJOR 1)
+set(GOOGLE_CLOUD_CPP_VERSION_MINOR 2)
+set(GOOGLE_CLOUD_CPP_VERSION_PATCH 0)
+string(CONCAT GOOGLE_CLOUD_CPP_VERSION "${GOOGLE_CLOUD_CPP_VERSION_MAJOR}" "."
+              "${GOOGLE_CLOUD_CPP_VERSION_MINOR}" "."
+              "${GOOGLE_CLOUD_CPP_VERSION_PATCH}")
 
 include(CTest)
 

ci/kokoro/docker/build.sh

@@ -120,7 +120,7 @@ elif [[ "${BUILD_NAME}" = "tsan" ]]; then
 elif [[ "${BUILD_NAME}" = "noex" ]]; then
   export DISTRO=fedora-install
   export DISTRO_VERSION=30
-  export CMAKE_FLAGS="-DGOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS=no"
+  export CMAKE_FLAGS="-DGOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS=no"
   in_docker_script="ci/kokoro/docker/build-in-docker-cmake.sh"
 elif [[ "${BUILD_NAME}" = "msan" ]]; then
   # We use Fedora for this build because (1) I was able to find instructions on

cmake/EnableCxxExceptions.cmake

@@ -14,23 +14,22 @@
 # limitations under the License.
 # ~~~
 
-option(GOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS
-       "Enable C++ Exception Support" ON)
+option(GOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS "Enable C++ Exception Support" ON)
 
 # If the user disabled C++ exceptions we should give them a heads up about the
 # consequences.
-if (NOT GOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS)
+if (NOT GOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS)
     message(
         WARNING
             "C++ Exceptions disabled, any operation that normally"
             " raises exceptions will instead log the error and call"
             " std::abort().  In addition, some examples and tests will not be"
             " compiled.")
     if (MSVC)
-        set(GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG "/EHs-c-")
+        set(GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG "/EHs-c-")
     else ()
-        set(GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG "-fno-exceptions")
+        set(GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG "-fno-exceptions")
     endif ()
 else ()
-    set(GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG "")
+    set(GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG "")
 endif ()

cmake/EnableDoxygen.cmake

@@ -61,15 +61,6 @@ else ()
         set(DOXYGEN_SOURCE_BROWSER YES)
         set(DOXYGEN_GENERATE_TAGFILE
             "${CMAKE_CURRENT_BINARY_DIR}/${GOOGLE_CLOUD_CPP_SUBPROJECT}.tag")
-        set(DOXYGEN_EXCLUDE_SYMBOLS "internal" "spanner_testing")
-        set(DOXYGEN_PREDEFINED
-            "SPANNER_CLIENT_NS=v${SPANNER_CLIENT_VERSION_MAJOR}")
-        set(DOXYGEN_EXCLUDE_PATTERNS
-            "*/google/cloud/spanner/README.md"
-            "*/google/cloud/spanner/internal/*"
-            "*/google/cloud/spanner/benchmarks/*"
-            "*/google/cloud/spanner/testing/*"
-            "*/google/cloud/spanner/*_test.cc")
         set(GOOGLE_CLOUD_CPP_COMMON_TAG_URL
             "https://googleapis.dev/cpp/google-cloud-common/")
         string(APPEND GOOGLE_CLOUD_CPP_COMMON_TAG_URL

cmake/GoogleCloudCppCommon.cmake

@@ -0,0 +1,102 @@
+# ~~~
+# Copyright 2018 Google LLC
+#
+# 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.
+# ~~~
+
+# Find out the name of the subproject.
+get_filename_component(GOOGLE_CLOUD_CPP_SUBPROJECT
+                       "${CMAKE_CURRENT_SOURCE_DIR}" NAME)
+
+# Find out what flags turn on all available warnings and turn those warnings
+# into errors.
+include(CheckCXXCompilerFlag)
+if (NOT MSVC)
+    check_cxx_compiler_flag(-Wall GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WALL)
+    check_cxx_compiler_flag(-Wextra GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WEXTRA)
+    check_cxx_compiler_flag(-Werror GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WERROR)
+else ()
+    check_cxx_compiler_flag("/std:c++latest"
+                            GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_CPP_LATEST)
+endif ()
+
+# If possible, enable a code coverage build type.
+include(EnableCoverage)
+
+# Include support for clang-tidy if available
+include(EnableClangTidy)
+
+# C++ Exceptions are enabled by default, but allow the user to turn them off.
+include(EnableCxxExceptions)
+
+# Get the destination directories based on the GNU recommendations.
+include(GNUInstallDirs)
+
+# Pick the right MSVC runtime libraries.
+include(SelectMSVCRuntime)
+
+# Enable doxygen
+include(EnableDoxygen)
+
+function (google_cloud_cpp_add_common_options target)
+    if (GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_CPP_LATEST)
+        target_compile_options(${target} INTERFACE "/std:c++latest")
+    endif ()
+    if (GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WALL)
+        target_compile_options(${target} INTERFACE "-Wall")
+    endif ()
+    if (GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WEXTRA)
+        target_compile_options(${target} INTERFACE "-Wextra")
+    endif ()
+    if (GOOGLE_CLOUD_CPP_COMPILER_SUPPORTS_WERROR)
+        target_compile_options(${target} INTERFACE "-Werror")
+    endif ()
+    if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU"
+        AND "${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS 5.0)
+        # With GCC 4.x this warning is too noisy to be useful.
+        target_compile_options(${target}
+                               INTERFACE "-Wno-missing-field-initializers")
+    endif ()
+endfunction ()
+
+function (google_cloud_cpp_add_clang_tidy target)
+    if (GOOGLE_CLOUD_CPP_CLANG_TIDY_PROGRAM AND GOOGLE_CLOUD_CPP_CLANG_TIDY)
+        set_target_properties(
+            ${target} PROPERTIES CXX_CLANG_TIDY
+                                 "${GOOGLE_CLOUD_CPP_CLANG_TIDY_PROGRAM}")
+    endif ()
+endfunction ()
+
+#
+# google_cloud_cpp_install_headers : install all the headers in a target
+#
+# Find all the headers in @p target and install them at @p destination,
+# preserving the directory structure.
+#
+# * target the name of the target.
+# * destination the destination directory, relative to <PREFIX>. Typically this
+#   starts with `include/google/cloud`, the function requires the full
+#   destination in case some headers get installed elsewhere in the future.
+#
+function (google_cloud_cpp_install_headers target destination)
+    get_target_property(target_sources ${target} SOURCES)
+    foreach (header ${target_sources})
+        if (NOT "${header}" MATCHES "\\.h$" AND NOT "${header}" MATCHES
+                                                "\\.inc$")
+            continue()
+        endif ()
+        string(REPLACE "${CMAKE_CURRENT_BINARY_DIR}/" "" relative "${header}")
+        get_filename_component(dir "${relative}" DIRECTORY)
+        install(FILES "${header}" DESTINATION "${destination}/${dir}")
+    endforeach ()
+endfunction ()

google/cloud/spanner/CMakeLists.txt

@@ -17,14 +17,19 @@
 find_package(google_cloud_cpp_common CONFIG REQUIRED)
 find_package(google_cloud_cpp_grpc_utils CONFIG REQUIRED)
 
-include(EnableClangTidy)
-include(EnableWerror)
 set(DOXYGEN_PROJECT_NAME "Google Cloud Spanner C++ Client")
 set(DOXYGEN_PROJECT_BRIEF "A C++ Client Library for Google Cloud Spanner")
-set(DOXYGEN_PROJECT_NUMBER "${SPANNER_CLIENT_VERSION}")
+set(DOXYGEN_PROJECT_NUMBER "${GOOGLE_CLOUD_CPP_CLIENT_VERSION}")
 set(DOXYGEN_EXAMPLE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/samples
                          ${CMAKE_CURRENT_SOURCE_DIR}/../../../quickstart)
-include(EnableDoxygen)
+set(DOXYGEN_EXCLUDE_SYMBOLS "internal" "spanner_testing")
+set(DOXYGEN_PREDEFINED "SPANNER_CLIENT_NS=v${GOOGLE_CLOUD_CPP_VERSION_MAJOR}")
+set(DOXYGEN_EXCLUDE_PATTERNS
+    "*/google/cloud/spanner/README.md" "*/google/cloud/spanner/internal/*"
+    "*/google/cloud/spanner/benchmarks/*" "*/google/cloud/spanner/testing/*"
+    "*/google/cloud/spanner/*_test.cc")
+
+include(GoogleCloudCppCommon)
 
 # Define a function to fetch the current git revision. Using a function creates
 # a new scope, so the CMake variables do not leak to the global namespace.
@@ -224,10 +229,10 @@ target_link_libraries(
     spanner_client PUBLIC google_cloud_cpp_grpc_utils google_cloud_cpp_common
                           googleapis-c++::spanner_protos)
 set_target_properties(
-    spanner_client PROPERTIES VERSION "${SPANNER_CLIENT_VERSION}"
-                              SOVERSION "${SPANNER_CLIENT_VERSION_MAJOR}")
+    spanner_client PROPERTIES VERSION "${GOOGLE_CLOUD_CPP_VERSION}"
+                              SOVERSION "${GOOGLE_CLOUD_CPP_VERSION_MAJOR}")
 target_compile_options(spanner_client
-                       PUBLIC ${GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG})
+                       PUBLIC ${GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG})
 
 google_cloud_cpp_add_clang_tidy(spanner_client)
 google_cloud_cpp_add_common_options(spanner_client)
@@ -260,7 +265,7 @@ target_include_directories(
               $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
               $<INSTALL_INTERFACE:include>)
 target_compile_options(spanner_client_mocks
-                       INTERFACE ${GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG})
+                       INTERFACE ${GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG})
 
 # Define the tests in a function so we have a new scope for variable names.
 function (spanner_client_define_tests)
@@ -311,7 +316,7 @@ function (spanner_client_define_tests)
                $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
                $<INSTALL_INTERFACE:include>)
     target_compile_options(spanner_client_testing
-                           PUBLIC ${GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG})
+                           PUBLIC ${GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG})
 
     set(spanner_client_unit_tests
         # cmake-format: sortable
@@ -454,12 +459,9 @@ add_subdirectory(benchmarks) # macro benchmarks
 
 # Only compile the samples if we're building with exceptions enabled. They
 # require exceptions to keep them simple and idiomatic.
-if (GOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS)
+if (GOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS)
     add_subdirectory(samples)
-endif (GOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS)
-
-# Get the destination directories based on the GNU recommendations.
-include(GNUInstallDirs)
+endif (GOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS)
 
 # Export the CMake targets to make it easy to create configuration files.
 install(EXPORT spanner-targets
@@ -493,15 +495,15 @@ google_cloud_cpp_install_headers("spanner_client_mocks"
                                  "include/google/cloud/spanner")
 
 # Setup global variables used in the following *.in files.
-set(GOOGLE_CLOUD_SPANNER_CONFIG_VERSION_MAJOR ${SPANNER_CLIENT_VERSION_MAJOR})
-set(GOOGLE_CLOUD_SPANNER_CONFIG_VERSION_MINOR ${SPANNER_CLIENT_VERSION_MINOR})
-set(GOOGLE_CLOUD_SPANNER_CONFIG_VERSION_PATCH ${SPANNER_CLIENT_VERSION_PATCH})
-set(GOOGLE_CLOUD_SPANNER_PC_NAME "The Google Cloud Spanner C++ Client Library")
-set(GOOGLE_CLOUD_SPANNER_PC_DESCRIPTION
+set(GOOGLE_CLOUD_CPP_CONFIG_VERSION_MAJOR ${GOOGLE_CLOUD_CPP_VERSION_MAJOR})
+set(GOOGLE_CLOUD_CPP_CONFIG_VERSION_MINOR ${GOOGLE_CLOUD_CPP_VERSION_MINOR})
+set(GOOGLE_CLOUD_CPP_CONFIG_VERSION_PATCH ${GOOGLE_CLOUD_CPP_VERSION_PATCH})
+set(GOOGLE_CLOUD_CPP_PC_NAME "The Google Cloud Spanner C++ Client Library")
+set(GOOGLE_CLOUD_CPP_PC_DESCRIPTION
     "Provides C++ APIs to access Google Cloud Spanner.")
-set(GOOGLE_CLOUD_SPANNER_PC_REQUIRES
+set(GOOGLE_CLOUD_CPP_PC_REQUIRES
     "google_cloud_cpp_grpc_utils google_cloud_cpp_common")
-set(GOOGLE_CLOUD_SPANNER_PC_LIBS "-lspanner_client")
+set(GOOGLE_CLOUD_CPP_PC_LIBS "-lspanner_client")
 
 # Create and install the pkg-config files.
 configure_file("${PROJECT_SOURCE_DIR}/google/cloud/spanner/config.pc.in"

google/cloud/spanner/benchmarks/CMakeLists.txt

@@ -54,7 +54,7 @@ function (spanner_client_define_benchmarks)
                $<BUILD_INTERFACE:${PROJECT_BINARY_DIR}>
                $<INSTALL_INTERFACE:include>)
     target_compile_options(spanner_client_benchmarks
-                           PUBLIC ${GOOGLE_CLOUD_CPP_SPANNER_EXCEPTIONS_FLAG})
+                           PUBLIC ${GOOGLE_CLOUD_CPP_EXCEPTIONS_FLAG})
 
     set(spanner_client_benchmark_programs
         # cmake-format: sortable

google/cloud/spanner/config-version.cmake.in

@@ -16,7 +16,7 @@ set(PACKAGE_VERSION @DOXYGEN_PROJECT_NUMBER@)
 
 # This package has not reached 1.0, there are no compatibility guarantees
 # before then.
-if (@SPANNER_CLIENT_VERSION@ EQUAL 0)
+if (@GOOGLE_CLOUD_CPP_VERSION@ EQUAL 0)
     if ("${PACKAGE_FIND_VERSION}" STREQUAL "")
         set(PACKAGE_VERSION_COMPATIBLE TRUE)
     elseif ("${PACKAGE_VERSION}" VERSION_EQUAL "${PACKAGE_FIND_VERSION}")

google/cloud/spanner/config.pc.in

@@ -17,10 +17,10 @@ exec_prefix=${prefix}/@CMAKE_INSTALL_BINDIR@
 libdir=${prefix}/@CMAKE_INSTALL_LIBDIR@
 includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
 
-Name: @GOOGLE_CLOUD_SPANNER_PC_NAME@
-Description: @GOOGLE_CLOUD_SPANNER_PC_DESCRIPTION@
-Requires: @GOOGLE_CLOUD_SPANNER_PC_REQUIRES@
+Name: @GOOGLE_CLOUD_CPP_PC_NAME@
+Description: @GOOGLE_CLOUD_CPP_PC_DESCRIPTION@
+Requires: @GOOGLE_CLOUD_CPP_PC_REQUIRES@
 Version: @DOXYGEN_PROJECT_NUMBER@
 
-Libs: -L${libdir} @GOOGLE_CLOUD_SPANNER_PC_LIBS@
+Libs: -L${libdir} @GOOGLE_CLOUD_CPP_PC_LIBS@
 Cflags: -I${includedir}

google/cloud/spanner/integration_tests/CMakeLists.txt

@@ -80,7 +80,7 @@ function (spanner_client_define_integration_tests)
             PROPERTY COMPILE_DEFINITIONS "_CRT_SECURE_NO_WARNINGS")
     endif ()
 
-    if (NOT GOOGLE_CLOUD_CPP_SPANNER_ENABLE_CXX_EXCEPTIONS)
+    if (NOT GOOGLE_CLOUD_CPP_ENABLE_CXX_EXCEPTIONS)
         return()
     endif ()