build: add coverage flags only when `ENABLE_COVERAGE` is `ON`

CMakeModules/testing_cpp.cmake

@@ -25,10 +25,12 @@ if (BUILD_TESTS)
     find_program(MEMORYCHECK_COMMAND valgrind)
     set(MEMORYCHECK_COMMAND_OPTIONS
             "--trace-children=yes --leak-check=full --error-exitcode=1 --num-callers=20 --suppressions=${CMAKE_SOURCE_DIR}/tests/valgrind.suppressions")
-    if (CMAKE_COMPILER_IS_GNUCXX)
-        include(CodeCoverage)
-        APPEND_COVERAGE_COMPILER_FLAGS()
-    endif ()
+    if (ENABLE_COVERAGE)
+        if (CMAKE_COMPILER_IS_GNUCXX)
+            include(CodeCoverage)
+            APPEND_COVERAGE_COMPILER_FLAGS()
+        endif ()
+    endif()
 endif ()
 
 #TODO: Call add_plain_unit_test in gtest
@@ -91,7 +93,7 @@ function(gtest target test_source_files linktarget)
         if (ARGN)
             LIST(GET ARGN 0 NOCOV)
         endif()
-        if (CMAKE_COMPILER_IS_GNUCXX AND NOT 1${NOCOV} STREQUAL "1nocov")
+        if (ENABLE_COVERAGE AND CMAKE_COMPILER_IS_GNUCXX AND NOT 1${NOCOV} STREQUAL "1nocov")
             set(COVERAGE_EXCLUDES "*/unittests/*" "*/3d_party/*" "*/python/*" "*/service_request*")
             if (ARGN)
                 set(COVERAGE_EXCLUDES ${COVERAGE_EXCLUDES} ${ARGN})