Update googletest, cmake and cleanup build variables

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "test/googletest"]
 	path = test/googletest
-	url = https://chromium.googlesource.com/external/googletest
+	url = https://github.com/google/googletest.git

.travis.yml

@@ -1,46 +1,43 @@
-#-----------------------------------------------------------------------------
-#
-#  Configuration for continuous integration service at travis-ci.org
-#
-#-----------------------------------------------------------------------------
-#
-# This file is copy of https://github.com/mapbox/protozero/blob/master/.travis.yml
-
 language: cpp
 
+branches:
+  only:
+  - master
+
 sudo: false
 
 matrix:
     include:
-        - os: linux
+        - dist: xenial
           compiler: clang
           env: INSTALL_CXX=clang++-3.5
           addons:
               apt:
                   sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.5', 'george-edison55-precise-backports']
                   packages: ['clang-3.5', 'lcov', 'cmake', 'cmake-data']
-        - os: linux
+        - dist: xenial
           compiler: clang
           env: INSTALL_CXX=clang++-3.6
           addons:
               apt:
                   sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.6', 'george-edison55-precise-backports']
                   packages: ['clang-3.6', 'lcov', 'cmake', 'cmake-data']
-        - os: linux
+        - dist: xenial
           compiler: gcc-4.8
           env: INSTALL_CXX=g++-4.8 INSTALL_CC=gcc-4.8
           addons:
               apt:
                   sources: ['ubuntu-toolchain-r-test', 'george-edison55-precise-backports']
                   packages: ['g++-4.8', 'lcov', 'cmake', 'cmake-data']
-        - os: linux
+        - dist: xenial
           compiler: gcc-4.9
           env: INSTALL_CXX=g++-4.9 INSTALL_CC=gcc-4.9
           addons:
               apt:
                   sources: ['ubuntu-toolchain-r-test', 'george-edison55-precise-backports']
                   packages: ['g++-4.9', 'lcov', 'cmake', 'cmake-data']
         - os: osx
+          osx_image: xcode10.1
           compiler: clang
           env: INSTALL_CXX=clang++ INSTALL_CC=clang
 
@@ -50,7 +47,7 @@ before_install:
 script:
     - mkdir -p build
     - cd build
-    - CC=$INSTALL_CC CXX=$INSTALL_CXX cmake ../ -DBUILD_COVERAGE:BOOL=ON
+    - CC=$INSTALL_CC CXX=$INSTALL_CXX cmake ../ -DMeshIO_BUILD_COVERAGE:BOOL=ON
     - make -j4
     - ctest --output-on-failure
 

CMakeLists.txt

@@ -1,67 +1,81 @@
-CMAKE_MINIMUM_REQUIRED(VERSION 3.0.2)
-
-PROJECT(MeshIO)
-
-SET(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/CMakeModules")
-
-OPTION(BUILD_DOCUMENTATION "Build Documentation" OFF)
-OPTION(BUILD_EXAMPLES "Build examples" OFF)
-OPTION(BUILD_TESTS "Build Tests" ON)
-OPTION(BUILD_COVERAGE "Create test coverage report" OFF)
-OPTION(USE_SYSTEM_GTEST "Use GTEST from system libraries" OFF)
-OPTION(USE_RELATIVE_TEST_DIR "Use relative paths for the test data directory(For continious integration(CI) purposes only)" OFF)
-
-# Set a default build type if none was specified
-IF(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
-    SET(CMAKE_BUILD_TYPE Release CACHE STRING "Choose the type of build." FORCE)
-    # Set the possible values of build type for cmake-gui
-    set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release"
-      "MinSizeRel" "RelWithDebInfo")
-ENDIF()
-
-### Marking BUILD_COVERAGE as advanced as it won't be
-### used by regular developers
-MARK_AS_ADVANCED(BUILD_COVERAGE)
-
-IF(UNIX)
-    IF("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
-        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
-    ELSEIF("${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS 4.7)
-        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
-    ELSE()
-        SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
-    ENDIF()
-ENDIF()
-
-# Generate documentation
-IF(BUILD_DOCUMENTATION)
-    ADD_SUBDIRECTORY(docs)
-ENDIF(BUILD_DOCUMENTATION)
-
-IF(BUILD_EXAMPLES)
-    ADD_SUBDIRECTORY(examples)
-ENDIF()
-
-IF(BUILD_TESTS)
-    ENABLE_TESTING()
-    ADD_SUBDIRECTORY(test)
-ENDIF()
-
-### Following commented out changes work only on CMAKE version >=3.0
-ADD_LIBRARY(MeshIO INTERFACE)
-TARGET_INCLUDE_DIRECTORIES(MeshIO INTERFACE
-           $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
-           $<INSTALL_INTERFACE:include/meshio>
-           )
-
-INSTALL(TARGETS MeshIO EXPORT meshioExport)
-INSTALL(EXPORT meshioExport NAMESPACE Upstream::
-       DESTINATION share/MeshIO/cmake
-       )
-
-INSTALL(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/include"
-        DESTINATION .
-        COMPONENT Headers
-        FILES_MATCHING
-        PATTERN "*.hpp"
-        )
+cmake_minimum_required(VERSION 3.12.3)
+
+project(MeshIO VERSION 0.1.0)
+
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
+
+if (NOT EXISTS "${MeshIO_SOURCE_DIR}/test/googletest")
+  message(WARNING "google/googletest is not available. Tests will not built.")
+  message("Did you miss the --recursive option when cloning?")
+  message("Run the following commands to correct this:")
+  message("git submodule init")
+  message("git submodule update")
+  message("git submodule foreach git pull origin master")
+endif ()
+
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+  set(CMAKE_BUILD_TYPE Release CACHE STRING "Choose the type of build." FORCE)
+  set_property(CACHE CMAKE_BUILD_TYPE
+      PROPERTY STRINGS "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
+endif()
+
+option(MeshIO_BUILD_DOCS "Build Documentation" OFF)
+option(MeshIO_BUILD_EXAMPLES "Build examples" OFF)
+option(MeshIO_BUILD_COVERAGE "Create test coverage report" OFF)
+
+add_library(meshio INTERFACE)
+
+target_include_directories(meshio INTERFACE
+  $<BUILD_INTERFACE:${MeshIO_SOURCE_DIR}/include>
+  $<INSTALL_INTERFACE:include>
+  )
+
+include(CTest)
+enable_testing()
+add_subdirectory(test)
+
+if(MeshIO_BUILD_DOCS)
+  add_subdirectory(docs)
+endif(MeshIO_BUILD_DOCS)
+
+if (MeshIO_BUILD_EXAMPLES)
+  add_subdirectory(examples)
+endif ()
+
+include(CMakePackageConfigHelpers)
+set(INCLUDE_DIRS include)
+set(CMAKE_DIR share/meshio/cmake)
+configure_package_config_file(
+    "${PROJECT_SOURCE_DIR}/cmake/MeshIOConfig.cmake.in"
+    "cmake_install/MeshIOConfig.cmake"
+    INSTALL_DESTINATION share/meshio/cmake
+    PATH_VARS INCLUDE_DIRS CMAKE_DIR
+)
+
+install(TARGETS meshio EXPORT MeshIOTargets COMPONENT meshio)
+
+install(EXPORT MeshIOTargets
+  NAMESPACE MeshIO::
+  DESTINATION share/meshio/cmake
+  COMPONENT meshio
+  )
+
+install(FILES
+  ${MeshIO_BINARY_DIR}/cmake_install/MeshIOConfig.cmake
+  DESTINATION share/meshio/cmake
+  COMPONENT cmake
+)
+
+install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/include"
+  DESTINATION .
+  COMPONENT Headers
+  FILES_MATCHING
+  PATTERN "*.hpp"
+  PATTERN "*.inl"
+  )
+
+mark_as_advanced(MeshIO_BUILD_COVERAGE)

cmake/MeshIOConfig.cmake.in

@@ -0,0 +1,42 @@
+#Copyright (c) 2019, Lakshman Anumolu, Pradeep Garigipati
+#All rights reserved.
+#
+#This file is part of MeshIO whose distribution is governed by
+#the BSD 2-Clause License contained in the accompanying LICENSE.txt
+#file.
+
+# MeshIO
+# -----
+#
+# This is the cmake configuration file for MeshIO header library. It provides
+# the following imported targets.
+#
+# ``MeshIO::meshio`` - the target for MeshIO
+#
+# This target can be used to link with your application using the
+# ``target_link_library`` command. Here is an example of how to use these
+# targets in your application:
+#
+#   add_executable(mybinary source.cpp)
+#   target_link_library(mybinary PRIVATE MeshIO::meshio)
+#
+# This example creates a mybinary executable from the source.cpp file and links
+# against the MeshIO library. Note you do *not* need to set the include
+# directories as they are automatically included with the target.
+#
+# This is the recommended way of linking against MeshIO
+
+@PACKAGE_INIT@
+
+set_and_check(MeshIO_INCLUDE_DIRS @PACKAGE_INCLUDE_DIRS@)
+
+if (NOT TARGET MeshIO::meshio AND NOT TARGET meshio AND
+    EXISTS @PACKAGE_CMAKE_DIR@/MeshIOTargets.cmake)
+  include(@PACKAGE_CMAKE_DIR@/MeshIOTargets.cmake)
+endif ()
+
+if (TARGET MeshIO::meshio OR TARGET meshio)
+  if (TARGET meshio AND NOT TARGET MeshIO::meshio)
+    add_library(MeshIO::meshio ALIAS meshio)
+  endif ()
+endif ()