cmake: Gate test-only libraries behind TESTONLY flag

Add TESTONLY to 16 tcmalloc_cc_library() calls that correspond to
testonly targets in the Bazel BUILD files but were being built
unconditionally in CMake. This ensures that when TCMALLOC_BUILD_TESTING
is OFF, no test-only source code is compiled.

Libraries marked TESTONLY:
  tcmalloc/CMakeLists.txt (7):
    - tcmalloc_tcmalloc_internal_methods_only
    - tcmalloc_mock_central_freelist
    - tcmalloc_mock_static_forwarder
    - tcmalloc_mock_virtual_allocator
    - tcmalloc_page_allocator_test_util
    - tcmalloc_mock_transfer_cache
    - tcmalloc_mock_huge_page_static_forwarder
  tcmalloc/internal/CMakeLists.txt (3):
    - tcmalloc_internal_affinity
    - tcmalloc_internal_mock_metadata_allocator
    - tcmalloc_internal_mock_span
  tcmalloc/testing/CMakeLists.txt (6):
    - tcmalloc_testing_malloc_hook_recorder
    - tcmalloc_testing_testutil
    - tcmalloc_testing_thread_manager
    - tcmalloc_testing_thread_ctor_test_lib
    - tcmalloc_testing_benchmark_main
    - tcmalloc_testing_test_allocator_harness

Also fixes the top-level CMakeLists.txt:
  - Move ABSL_BUILD_TEST_HELPERS, ABSL_USE_EXTERNAL_GOOGLETEST, and
    ABSL_FIND_GOOGLETEST behind the testing guard so abseil does not
    attempt to fetch googletest when tests are disabled.
  - Move protobuf out of the test-only dependency block since
    profile_builder and profile_marshaler are core (non-testonly)
    libraries that require it.

Author: gtkramer

CMakeLists.txt

@@ -54,9 +54,12 @@ option(TCMALLOC_BUILD_TEST_HELPERS
   "If ON, TCMalloc will build test helper libraries." OFF)
 
 set(ABSL_BUILD_TESTING OFF CACHE BOOL "" FORCE)
-set(ABSL_BUILD_TEST_HELPERS ON CACHE BOOL "" FORCE)
-set(ABSL_USE_EXTERNAL_GOOGLETEST ON CACHE BOOL "" FORCE)
-set(ABSL_FIND_GOOGLETEST OFF CACHE BOOL "" FORCE)
+
+if((BUILD_TESTING AND TCMALLOC_BUILD_TESTING) OR TCMALLOC_BUILD_TEST_HELPERS)
+  set(ABSL_BUILD_TEST_HELPERS ON CACHE BOOL "" FORCE)
+  set(ABSL_USE_EXTERNAL_GOOGLETEST ON CACHE BOOL "" FORCE)
+  set(ABSL_FIND_GOOGLETEST OFF CACHE BOOL "" FORCE)
+endif()
 
 include(FetchContent)
 
@@ -94,6 +97,30 @@ else()
   endif()
 endif()
 
+# -- Protobuf (required by profile_builder / profile_marshaler) --
+option(TCMALLOC_USE_EXTERNAL_PROTOBUF
+  "If ON, assume Protobuf targets are already provided." OFF)
+set(TCMALLOC_LOCAL_PROTOBUF_DIR "" CACHE PATH
+  "Path to a local protobuf source directory.")
+
+if(TCMALLOC_USE_EXTERNAL_PROTOBUF)
+  if(NOT TARGET protobuf::libprotobuf)
+    find_package(Protobuf REQUIRED)
+  endif()
+else()
+  if(TCMALLOC_LOCAL_PROTOBUF_DIR)
+    add_subdirectory("${TCMALLOC_LOCAL_PROTOBUF_DIR}" protobuf EXCLUDE_FROM_ALL)
+  else()
+    FetchContent_Declare(
+      protobuf
+      GIT_REPOSITORY https://github.com/protocolbuffers/protobuf.git
+      GIT_TAG        main
+      FIND_PACKAGE_ARGS NAMES Protobuf
+    )
+    FetchContent_MakeAvailable(protobuf)
+  endif()
+endif()
+
 # -- Test-only dependencies --
 if((BUILD_TESTING AND TCMALLOC_BUILD_TESTING) OR TCMALLOC_BUILD_TEST_HELPERS)
 
@@ -127,30 +154,6 @@ if((BUILD_TESTING AND TCMALLOC_BUILD_TESTING) OR TCMALLOC_BUILD_TEST_HELPERS)
     endif()
   endif()
 
-  # Protobuf
-  option(TCMALLOC_USE_EXTERNAL_PROTOBUF
-    "If ON, assume Protobuf targets are already provided." OFF)
-  set(TCMALLOC_LOCAL_PROTOBUF_DIR "" CACHE PATH
-    "Path to a local protobuf source directory.")
-
-  if(TCMALLOC_USE_EXTERNAL_PROTOBUF)
-    if(NOT TARGET protobuf::libprotobuf)
-      find_package(Protobuf REQUIRED)
-    endif()
-  else()
-    if(TCMALLOC_LOCAL_PROTOBUF_DIR)
-      add_subdirectory("${TCMALLOC_LOCAL_PROTOBUF_DIR}" protobuf EXCLUDE_FROM_ALL)
-    else()
-      FetchContent_Declare(
-        protobuf
-        GIT_REPOSITORY https://github.com/protocolbuffers/protobuf.git
-        GIT_TAG        main
-        FIND_PACKAGE_ARGS NAMES Protobuf
-      )
-      FetchContent_MakeAvailable(protobuf)
-    endif()
-  endif()
-
   # Google Benchmark
   option(TCMALLOC_USE_EXTERNAL_BENCHMARK
     "If ON, assume Google Benchmark targets are already provided." OFF)

tcmalloc/CMakeLists.txt

@@ -86,6 +86,7 @@ tcmalloc_cc_library(
     tcmalloc_tcmalloc_internal_methods_only
   ALIAS
     tcmalloc::tcmalloc_internal_methods_only
+  TESTONLY
   HDRS
     "tcmalloc.h"
   SRCS
@@ -722,6 +723,7 @@ tcmalloc_cc_library(
     tcmalloc_mock_central_freelist
   ALIAS
     tcmalloc::mock_central_freelist
+  TESTONLY
   HDRS
     "mock_central_freelist.h"
   SRCS
@@ -740,6 +742,7 @@ tcmalloc_cc_library(
     tcmalloc_mock_static_forwarder
   ALIAS
     tcmalloc::mock_static_forwarder
+  TESTONLY
   HDRS
     "mock_static_forwarder.h"
   DEPS
@@ -756,6 +759,7 @@ tcmalloc_cc_library(
     tcmalloc_mock_virtual_allocator
   ALIAS
     tcmalloc::mock_virtual_allocator
+  TESTONLY
   HDRS
     "mock_virtual_allocator.h"
   DEPS
@@ -771,6 +775,7 @@ tcmalloc_cc_library(
     tcmalloc_page_allocator_test_util
   ALIAS
     tcmalloc::page_allocator_test_util
+  TESTONLY
   HDRS
     "page_allocator_test_util.h"
   SRCS
@@ -788,6 +793,7 @@ tcmalloc_cc_library(
     tcmalloc_mock_transfer_cache
   ALIAS
     tcmalloc::mock_transfer_cache
+  TESTONLY
   HDRS
     "mock_transfer_cache.h"
   SRCS
@@ -809,6 +815,7 @@ tcmalloc_cc_library(
     tcmalloc_mock_huge_page_static_forwarder
   ALIAS
     tcmalloc::mock_huge_page_static_forwarder
+  TESTONLY
   HDRS
     "mock_huge_page_static_forwarder.h"
   SRCS

tcmalloc/internal/CMakeLists.txt

@@ -17,6 +17,7 @@ tcmalloc_cc_library(
     tcmalloc_internal_affinity
   ALIAS
     tcmalloc::internal_affinity
+  TESTONLY
   HDRS
     "affinity.h"
   SRCS
@@ -497,6 +498,7 @@ tcmalloc_cc_library(
     tcmalloc_internal_mock_metadata_allocator
   ALIAS
     tcmalloc::internal_mock_metadata_allocator
+  TESTONLY
   HDRS
     "mock_metadata_allocator.h"
   DEPS
@@ -573,6 +575,7 @@ tcmalloc_cc_library(
     tcmalloc_internal_mock_span
   ALIAS
     tcmalloc::internal_mock_span
+  TESTONLY
   HDRS
     "mock_span.h"
   DEPS

tcmalloc/testing/CMakeLists.txt

@@ -17,6 +17,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_malloc_hook_recorder
   ALIAS
     tcmalloc::testing_malloc_hook_recorder
+  TESTONLY
   HDRS
     "malloc_hook_recorder.h"
   SRCS
@@ -34,6 +35,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_testutil
   ALIAS
     tcmalloc::testing_testutil
+  TESTONLY
   HDRS
     "testutil.h"
   SRCS
@@ -231,6 +233,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_thread_manager
   ALIAS
     tcmalloc::testing_thread_manager
+  TESTONLY
   HDRS
     "thread_manager.h"
   DEPS
@@ -353,6 +356,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_thread_ctor_test_lib
   ALIAS
     tcmalloc::testing_thread_ctor_test_lib
+  TESTONLY
   SRCS
     "thread_ctor_test_lib.cc"
   LINKOPTS
@@ -610,6 +614,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_benchmark_main
   ALIAS
     tcmalloc::testing_benchmark_main
+  TESTONLY
   SRCS
     "benchmark_main.cc"
   DEPS
@@ -650,6 +655,7 @@ tcmalloc_cc_library(
     tcmalloc_testing_test_allocator_harness
   ALIAS
     tcmalloc::testing_test_allocator_harness
+  TESTONLY
   HDRS
     "test_allocator_harness.h"
   DEPS