diff --git a/cmake/CodeCoverage.cmake b/cmake/CodeCoverage.cmake
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+# Copyright (c) 2012 - 2017, Lars Bilke
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice, this
+#    list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+#    this list of conditions and the following disclaimer in the documentation
+#    and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+#    may be used to endorse or promote products derived from this software without
+#    specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+# ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# CHANGES:
+#
+# 2012-01-31, Lars Bilke
+# - Enable Code Coverage
+#
+# 2013-09-17, Joakim Söderberg
+# - Added support for Clang.
+# - Some additional usage instructions.
+#
+# 2016-02-03, Lars Bilke
+# - Refactored functions to use named parameters
+#
+# 2017-06-02, Lars Bilke
+# - Merged with modified version from github.com/ufz/ogs
+#
+# 2019-05-06, Anatolii Kurotych
+# - Remove unnecessary --coverage flag
+#
+# 2019-12-13, FeRD (Frank Dana)
+# - Deprecate COVERAGE_LCOVR_EXCLUDES and COVERAGE_GCOVR_EXCLUDES lists in favor
+#   of tool-agnostic COVERAGE_EXCLUDES variable, or EXCLUDE setup arguments.
+# - CMake 3.4+: All excludes can be specified relative to BASE_DIRECTORY
+# - All setup functions: accept BASE_DIRECTORY, EXCLUDE list
+# - Set lcov basedir with -b argument
+# - Add automatic --demangle-cpp in lcovr, if 'c++filt' is available (can be
+#   overridden with NO_DEMANGLE option in setup_target_for_coverage_lcovr().)
+# - Delete output dir, .info file on 'make clean'
+# - Remove Python detection, since version mismatches will break gcovr
+# - Minor cleanup (lowercase function names, update examples...)
+#
+# 2019-12-19, FeRD (Frank Dana)
+# - Rename Lcov outputs, make filtered file canonical, fix cleanup for targets
+#
+# 2020-01-19, Bob Apthorpe
+# - Added gfortran support
+#
+# 2020-02-17, FeRD (Frank Dana)
+# - Make all add_custom_target()s VERBATIM to auto-escape wildcard characters
+#   in EXCLUDEs, and remove manual escaping from gcovr targets
+#
+# 2020-09-02, Rui Zhang
+# - Copied from https://github.com/bilke/cmake-modules/blob/master/CodeCoverage.cmake
+# - No changes
+#
+# USAGE:
+#
+# 1. Copy this file into your cmake modules path.
+#
+# 2. Add the following line to your CMakeLists.txt (best inside an if-condition
+#    using a CMake option() to enable it just optionally):
+#      include(CodeCoverage)
+#
+# 3. Append necessary compiler flags:
+#      append_coverage_compiler_flags()
+#
+# 3.a (OPTIONAL) Set appropriate optimization flags, e.g. -O0, -O1 or -Og
+#
+# 4. If you need to exclude additional directories from the report, specify them
+#    using full paths in the COVERAGE_EXCLUDES variable before calling
+#    setup_target_for_coverage_*().
+#    Example:
+#      set(COVERAGE_EXCLUDES
+#          '${PROJECT_SOURCE_DIR}/src/dir1/*'
+#          '/path/to/my/src/dir2/*')
+#    Or, use the EXCLUDE argument to setup_target_for_coverage_*().
+#    Example:
+#      setup_target_for_coverage_lcov(
+#          NAME coverage
+#          EXECUTABLE testrunner
+#          EXCLUDE "${PROJECT_SOURCE_DIR}/src/dir1/*" "/path/to/my/src/dir2/*")
+#
+# 4.a NOTE: With CMake 3.4+, COVERAGE_EXCLUDES or EXCLUDE can also be set
+#     relative to the BASE_DIRECTORY (default: PROJECT_SOURCE_DIR)
+#     Example:
+#       set(COVERAGE_EXCLUDES "dir1/*")
+#       setup_target_for_coverage_gcovr_html(
+#           NAME coverage
+#           EXECUTABLE testrunner
+#           BASE_DIRECTORY "${PROJECT_SOURCE_DIR}/src"
+#           EXCLUDE "dir2/*")
+#
+# 5. Use the functions described below to create a custom make target which
+#    runs your test executable and produces a code coverage report.
+#
+# 6. Build a Debug build:
+#      cmake -DCMAKE_BUILD_TYPE=Debug ..
+#      make
+#      make my_coverage_target
+#
+include(CMakeParseArguments)
+# Check prereqs
+find_program( GCOV_PATH gcov )
+find_program( LCOV_PATH  NAMES lcov lcov.bat lcov.exe lcov.perl)
+find_program( GENHTML_PATH NAMES genhtml genhtml.perl genhtml.bat )
+find_program( GCOVR_PATH gcovr PATHS ${CMAKE_SOURCE_DIR}/scripts/test)
+find_program( CPPFILT_PATH NAMES c++filt )
+if(NOT GCOV_PATH)
+    message(FATAL_ERROR "gcov not found! Aborting...")
+endif() # NOT GCOV_PATH
+if("${CMAKE_CXX_COMPILER_ID}" MATCHES "(Apple)?[Cc]lang")
+    if("${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS 3)
+        message(FATAL_ERROR "Clang version must be 3.0.0 or greater! Aborting...")
+    endif()
+elseif(NOT CMAKE_COMPILER_IS_GNUCXX)
+    if("${CMAKE_Fortran_COMPILER_ID}" MATCHES "[Ff]lang")
+        # Do nothing; exit conditional without error if true
+    elseif("${CMAKE_Fortran_COMPILER_ID}" MATCHES "GNU")
+        # Do nothing; exit conditional without error if true
+    else()
+        message(FATAL_ERROR "Compiler is not GNU gcc! Aborting...")
+    endif()
+endif()
+set(COVERAGE_COMPILER_FLAGS "-g -fprofile-arcs -ftest-coverage"
+    CACHE INTERNAL "")
+set(CMAKE_Fortran_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the Fortran compiler during coverage builds."
+    FORCE )
+set(CMAKE_CXX_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the C++ compiler during coverage builds."
+    FORCE )
+set(CMAKE_C_FLAGS_COVERAGE
+    ${COVERAGE_COMPILER_FLAGS}
+    CACHE STRING "Flags used by the C compiler during coverage builds."
+    FORCE )
+set(CMAKE_EXE_LINKER_FLAGS_COVERAGE
+    ""
+    CACHE STRING "Flags used for linking binaries during coverage builds."
+    FORCE )
+set(CMAKE_SHARED_LINKER_FLAGS_COVERAGE
+    ""
+    CACHE STRING "Flags used by the shared libraries linker during coverage builds."
+    FORCE )
+mark_as_advanced(
+    CMAKE_Fortran_FLAGS_COVERAGE
+    CMAKE_CXX_FLAGS_COVERAGE
+    CMAKE_C_FLAGS_COVERAGE
+    CMAKE_EXE_LINKER_FLAGS_COVERAGE
+    CMAKE_SHARED_LINKER_FLAGS_COVERAGE )
+if(NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
+    message(WARNING "Code coverage results with an optimised (non-Debug) build may be misleading")
+endif() # NOT CMAKE_BUILD_TYPE STREQUAL "Debug"
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU" OR CMAKE_Fortran_COMPILER_ID STREQUAL "GNU")
+    link_libraries(gcov)
+endif()
+# Defines a target for running and collection code coverage information
+# Builds dependencies, runs the given executable and outputs reports.
+# NOTE! The executable should always have a ZERO as exit code otherwise
+# the coverage generation will not complete.
+#
+# setup_target_for_coverage_lcov(
+#     NAME testrunner_coverage                    # New target name
+#     EXECUTABLE testrunner -j ${PROCESSOR_COUNT} # Executable in PROJECT_BINARY_DIR
+#     DEPENDENCIES testrunner                     # Dependencies to build first
+#     BASE_DIRECTORY "../"                        # Base directory for report
+#                                                 #  (defaults to PROJECT_SOURCE_DIR)
+#     EXCLUDE "src/dir1/*" "src/dir2/*"           # Patterns to exclude (can be relative
+#                                                 #  to BASE_DIRECTORY, with CMake 3.4+)
+#     NO_DEMANGLE                                 # Don't demangle C++ symbols
+#                                                 #  even if c++filt is found
+# )
+function(setup_target_for_coverage_lcov)
+    set(options NO_DEMANGLE)
+    set(oneValueArgs BASE_DIRECTORY NAME)
+    set(multiValueArgs EXCLUDE EXECUTABLE EXECUTABLE_ARGS DEPENDENCIES LCOV_ARGS GENHTML_ARGS)
+    cmake_parse_arguments(Coverage "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    if(NOT LCOV_PATH)
+        message(FATAL_ERROR "lcov not found! Aborting...")
+    endif() # NOT LCOV_PATH
+    if(NOT GENHTML_PATH)
+        message(FATAL_ERROR "genhtml not found! Aborting...")
+    endif() # NOT GENHTML_PATH
+    # Set base directory (as absolute path), or default to PROJECT_SOURCE_DIR
+    if(${Coverage_BASE_DIRECTORY})
+        get_filename_component(BASEDIR ${Coverage_BASE_DIRECTORY} ABSOLUTE)
+    else()
+        set(BASEDIR ${PROJECT_SOURCE_DIR})
+    endif()
+    # Collect excludes (CMake 3.4+: Also compute absolute paths)
+    set(LCOV_EXCLUDES "")
+    foreach(EXCLUDE ${Coverage_EXCLUDE} ${COVERAGE_EXCLUDES} ${COVERAGE_LCOV_EXCLUDES})
+        if(CMAKE_VERSION VERSION_GREATER 3.4)
+            get_filename_component(EXCLUDE ${EXCLUDE} ABSOLUTE BASE_DIR ${BASEDIR})
+        endif()
+        list(APPEND LCOV_EXCLUDES "${EXCLUDE}")
+    endforeach()
+    list(REMOVE_DUPLICATES LCOV_EXCLUDES)
+    # Conditional arguments
+    if(CPPFILT_PATH AND NOT ${Coverage_NO_DEMANGLE})
+      set(GENHTML_EXTRA_ARGS "--demangle-cpp")
+    endif()
+    # Setup target
+    add_custom_target(${Coverage_NAME}
+        # Cleanup lcov
+        COMMAND ${LCOV_PATH} ${Coverage_LCOV_ARGS} --gcov-tool ${GCOV_PATH} -directory . -b ${BASEDIR} --zerocounters
+        # Create baseline to make sure untouched files show up in the report
+        COMMAND ${LCOV_PATH} ${Coverage_LCOV_ARGS} --gcov-tool ${GCOV_PATH} -c -i -d . -b ${BASEDIR} -o ${Coverage_NAME}.base
+        # Run tests
+        COMMAND ${Coverage_EXECUTABLE} ${Coverage_EXECUTABLE_ARGS}
+        # Capturing lcov counters and generating report
+        COMMAND ${LCOV_PATH} ${Coverage_LCOV_ARGS} --gcov-tool ${GCOV_PATH} --directory . -b ${BASEDIR} --capture --output-file ${Coverage_NAME}.capture
+        # add baseline counters
+        COMMAND ${LCOV_PATH} ${Coverage_LCOV_ARGS} --gcov-tool ${GCOV_PATH} -a ${Coverage_NAME}.base -a ${Coverage_NAME}.capture --output-file ${Coverage_NAME}.total
+        # filter collected data to final coverage report
+        COMMAND ${LCOV_PATH} ${Coverage_LCOV_ARGS} --gcov-tool ${GCOV_PATH} --remove ${Coverage_NAME}.total ${LCOV_EXCLUDES} --output-file ${Coverage_NAME}.info
+        # Generate HTML output
+        COMMAND ${GENHTML_PATH} ${GENHTML_EXTRA_ARGS} ${Coverage_GENHTML_ARGS} -o ${Coverage_NAME} ${Coverage_NAME}.info
+        # Set output files as GENERATED (will be removed on 'make clean')
+        BYPRODUCTS
+            ${Coverage_NAME}.base
+            ${Coverage_NAME}.capture
+            ${Coverage_NAME}.total
+            ${Coverage_NAME}.info
+            ${Coverage_NAME}  # report directory
+        WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+        DEPENDS ${Coverage_DEPENDENCIES}
+        VERBATIM # Protect arguments to commands
+        COMMENT "Resetting code coverage counters to zero.\nProcessing code coverage counters and generating report."
+    )
+    # Show where to find the lcov info report
+    add_custom_command(TARGET ${Coverage_NAME} POST_BUILD
+        COMMAND ;
+        COMMENT "Lcov code coverage info report saved in ${Coverage_NAME}.info."
+    )
+    # Show info where to find the report
+    add_custom_command(TARGET ${Coverage_NAME} POST_BUILD
+        COMMAND ;
+        COMMENT "Open ./${Coverage_NAME}/index.html in your browser to view the coverage report."
+    )
+endfunction() # setup_target_for_coverage_lcov
+# Defines a target for running and collection code coverage information
+# Builds dependencies, runs the given executable and outputs reports.
+# NOTE! The executable should always have a ZERO as exit code otherwise
+# the coverage generation will not complete.
+#
+# setup_target_for_coverage_gcovr_xml(
+#     NAME ctest_coverage                    # New target name
+#     EXECUTABLE ctest -j ${PROCESSOR_COUNT} # Executable in PROJECT_BINARY_DIR
+#     DEPENDENCIES executable_target         # Dependencies to build first
+#     BASE_DIRECTORY "../"                   # Base directory for report
+#                                            #  (defaults to PROJECT_SOURCE_DIR)
+#     EXCLUDE "src/dir1/*" "src/dir2/*"      # Patterns to exclude (can be relative
+#                                            #  to BASE_DIRECTORY, with CMake 3.4+)
+# )
+function(setup_target_for_coverage_gcovr_xml)
+    set(options NONE)
+    set(oneValueArgs BASE_DIRECTORY NAME)
+    set(multiValueArgs EXCLUDE EXECUTABLE EXECUTABLE_ARGS DEPENDENCIES)
+    cmake_parse_arguments(Coverage "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    if(NOT GCOVR_PATH)
+        message(FATAL_ERROR "gcovr not found! Aborting...")
+    endif() # NOT GCOVR_PATH
+    # Set base directory (as absolute path), or default to PROJECT_SOURCE_DIR
+    if(${Coverage_BASE_DIRECTORY})
+        get_filename_component(BASEDIR ${Coverage_BASE_DIRECTORY} ABSOLUTE)
+    else()
+        set(BASEDIR ${PROJECT_SOURCE_DIR})
+    endif()
+    # Collect excludes (CMake 3.4+: Also compute absolute paths)
+    set(GCOVR_EXCLUDES "")
+    foreach(EXCLUDE ${Coverage_EXCLUDE} ${COVERAGE_EXCLUDES} ${COVERAGE_GCOVR_EXCLUDES})
+        if(CMAKE_VERSION VERSION_GREATER 3.4)
+            get_filename_component(EXCLUDE ${EXCLUDE} ABSOLUTE BASE_DIR ${BASEDIR})
+        endif()
+        list(APPEND GCOVR_EXCLUDES "${EXCLUDE}")
+    endforeach()
+    list(REMOVE_DUPLICATES GCOVR_EXCLUDES)
+    # Combine excludes to several -e arguments
+    set(GCOVR_EXCLUDE_ARGS "")
+    foreach(EXCLUDE ${GCOVR_EXCLUDES})
+        list(APPEND GCOVR_EXCLUDE_ARGS "-e")
+        list(APPEND GCOVR_EXCLUDE_ARGS "${EXCLUDE}")
+    endforeach()
+    add_custom_target(${Coverage_NAME}
+        # Run tests
+        ${Coverage_EXECUTABLE} ${Coverage_EXECUTABLE_ARGS}
+        # Running gcovr
+        COMMAND ${GCOVR_PATH} --xml
+            -r ${BASEDIR} ${GCOVR_EXCLUDE_ARGS}
+            --object-directory=${PROJECT_BINARY_DIR}
+            -o ${Coverage_NAME}.xml
+        BYPRODUCTS ${Coverage_NAME}.xml
+        WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+        DEPENDS ${Coverage_DEPENDENCIES}
+        VERBATIM # Protect arguments to commands
+        COMMENT "Running gcovr to produce Cobertura code coverage report."
+    )
+    # Show info where to find the report
+    add_custom_command(TARGET ${Coverage_NAME} POST_BUILD
+        COMMAND ;
+        COMMENT "Cobertura code coverage report saved in ${Coverage_NAME}.xml."
+    )
+endfunction() # setup_target_for_coverage_gcovr_xml
+# Defines a target for running and collection code coverage information
+# Builds dependencies, runs the given executable and outputs reports.
+# NOTE! The executable should always have a ZERO as exit code otherwise
+# the coverage generation will not complete.
+#
+# setup_target_for_coverage_gcovr_html(
+#     NAME ctest_coverage                    # New target name
+#     EXECUTABLE ctest -j ${PROCESSOR_COUNT} # Executable in PROJECT_BINARY_DIR
+#     DEPENDENCIES executable_target         # Dependencies to build first
+#     BASE_DIRECTORY "../"                   # Base directory for report
+#                                            #  (defaults to PROJECT_SOURCE_DIR)
+#     EXCLUDE "src/dir1/*" "src/dir2/*"      # Patterns to exclude (can be relative
+#                                            #  to BASE_DIRECTORY, with CMake 3.4+)
+# )
+function(setup_target_for_coverage_gcovr_html)
+    set(options NONE)
+    set(oneValueArgs BASE_DIRECTORY NAME)
+    set(multiValueArgs EXCLUDE EXECUTABLE EXECUTABLE_ARGS DEPENDENCIES)
+    cmake_parse_arguments(Coverage "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    if(NOT GCOVR_PATH)
+        message(FATAL_ERROR "gcovr not found! Aborting...")
+    endif() # NOT GCOVR_PATH
+    # Set base directory (as absolute path), or default to PROJECT_SOURCE_DIR
+    if(${Coverage_BASE_DIRECTORY})
+        get_filename_component(BASEDIR ${Coverage_BASE_DIRECTORY} ABSOLUTE)
+    else()
+        set(BASEDIR ${PROJECT_SOURCE_DIR})
+    endif()
+    # Collect excludes (CMake 3.4+: Also compute absolute paths)
+    set(GCOVR_EXCLUDES "")
+    foreach(EXCLUDE ${Coverage_EXCLUDE} ${COVERAGE_EXCLUDES} ${COVERAGE_GCOVR_EXCLUDES})
+        if(CMAKE_VERSION VERSION_GREATER 3.4)
+            get_filename_component(EXCLUDE ${EXCLUDE} ABSOLUTE BASE_DIR ${BASEDIR})
+        endif()
+        list(APPEND GCOVR_EXCLUDES "${EXCLUDE}")
+    endforeach()
+    list(REMOVE_DUPLICATES GCOVR_EXCLUDES)
+    # Combine excludes to several -e arguments
+    set(GCOVR_EXCLUDE_ARGS "")
+    foreach(EXCLUDE ${GCOVR_EXCLUDES})
+        list(APPEND GCOVR_EXCLUDE_ARGS "-e")
+        list(APPEND GCOVR_EXCLUDE_ARGS "${EXCLUDE}")
+    endforeach()
+    add_custom_target(${Coverage_NAME}
+        # Run tests
+        ${Coverage_EXECUTABLE} ${Coverage_EXECUTABLE_ARGS}
+        # Create folder
+        COMMAND ${CMAKE_COMMAND} -E make_directory ${PROJECT_BINARY_DIR}/${Coverage_NAME}
+        # Running gcovr
+        COMMAND ${GCOVR_PATH} --html --html-details
+            -r ${BASEDIR} ${GCOVR_EXCLUDE_ARGS}
+            --object-directory=${PROJECT_BINARY_DIR}
+            -o ${Coverage_NAME}/index.html
+        BYPRODUCTS ${PROJECT_BINARY_DIR}/${Coverage_NAME}  # report directory
+        WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+        DEPENDS ${Coverage_DEPENDENCIES}
+        VERBATIM # Protect arguments to commands
+        COMMENT "Running gcovr to produce HTML code coverage report."
+    )
+    # Show info where to find the report
+    add_custom_command(TARGET ${Coverage_NAME} POST_BUILD
+        COMMAND ;
+        COMMENT "Open ./${Coverage_NAME}/index.html in your browser to view the coverage report."
+    )
+endfunction() # setup_target_for_coverage_gcovr_html
+function(append_coverage_compiler_flags)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    set(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} ${COVERAGE_COMPILER_FLAGS}" PARENT_SCOPE)
+    message(STATUS "Appending code coverage compiler flags: ${COVERAGE_COMPILER_FLAGS}")
+endfunction() # append_coverage_compiler_flags
+