Fix tests and benchmarks compilation

Compilation of some of the tests was failing with:
"undefined reference to `facebook::cachelib::test_util::getRandomAsciiStr[abi:cxx11](unsigned int)'"

Fix this by linking those tests with common/TestUtils.cpp

Also, for some reason specyfing sources as in
add_library(common_test_support INTERFACE [sources...]) did not work.
Using target_sources works fine.

Author: igchor

cachelib/allocator/CMakeLists.txt

@@ -81,6 +81,7 @@ if (BUILD_TESTS)
     ${DATASTRUCT_TESTS_THRIFT_FILES}
     ./nvmcache/tests/NvmTestBase.cpp
     ./memory/tests/TestBase.cpp
+    ../common/TestUtils.cpp
     )
   add_dependencies(allocator_test_support thrift_generated_files)
   target_link_libraries (allocator_test_support PUBLIC

cachelib/benchmarks/CMakeLists.txt

@@ -17,6 +17,7 @@ add_thrift_file(DATATYPEBENCH DataTypeBench.thrift frozen2)
 if (BUILD_TESTS)
   add_library (benchmark_test_support
     ${DATATYPEBENCH_THRIFT_FILES}
+    ../common/TestUtils.cpp
     )
 
   add_dependencies(benchmark_test_support thrift_generated_files)

cachelib/common/CMakeLists.txt

@@ -47,27 +47,19 @@ install(TARGETS cachelib_common
 
 
 if (BUILD_TESTS)
-  add_library (common_test_utils STATIC
-    TestUtils.cpp
-  )
-  target_link_libraries (common_test_utils PUBLIC
+  add_library (common_test_support INTERFACE)
+  target_link_libraries (common_test_support INTERFACE
     cachelib_common
+    common_test_utils
     gflags
     GTest::gtest
     GTest::gtest_main
   )
-  add_library (common_test_support OBJECT
+  target_sources(common_test_support INTERFACE
+    TestUtils.cpp
     hothash/HotHashDetectorTest.cpp
     piecewise/GenericPiecesTest.cpp
-    piecewise/RequestRangeTest.cpp
-  )
-  target_link_libraries (common_test_support PUBLIC
-    cachelib_common
-    common_test_utils
-    gflags
-    GTest::gtest
-    GTest::gtest_main
-  )
+    piecewise/RequestRangeTest.cpp)
 
   function (ADD_TEST SOURCE_FILE)
      # Add any additional libraries BEFORE the "common_test_support" to ensure

cachelib/compact_cache/CMakeLists.txt

@@ -23,6 +23,7 @@ if (BUILD_TESTS)
     GTest::gtest
     GTest::gmock
   )
+  target_sources(compact_cache_test_support INTERFACE ../common/TestUtils.cpp)
 
   function (ADD_TEST SOURCE_FILE)
      generic_add_test("compact-cache-test" "${SOURCE_FILE}"