bpo-40280: Allow to compile _testcapi as builtin module (GH-30559)

Modules/Setup.stdlib.in

@@ -169,11 +169,10 @@
 @MODULE__XXTESTFUZZ_TRUE@_xxtestfuzz _xxtestfuzz/_xxtestfuzz.c _xxtestfuzz/fuzzer.c
 @MODULE__TESTBUFFER_TRUE@_testbuffer _testbuffer.c
 @MODULE__TESTINTERNALCAPI_TRUE@_testinternalcapi _testinternalcapi.c
-
+@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c
 
 # Some testing modules MUST be built as shared libraries.
 *shared*
-@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c
 @MODULE__TESTIMPORTMULTIPLE_TRUE@_testimportmultiple _testimportmultiple.c
 @MODULE__TESTMULTIPHASE_TRUE@_testmultiphase _testmultiphase.c
 @MODULE__CTYPES_TEST_TRUE@_ctypes_test _ctypes/_ctypes_test.c

Modules/_testcapimodule.c

@@ -12,6 +12,8 @@
    macro defined, but only the public C API must be tested here. */
 
 #undef Py_BUILD_CORE_MODULE
+#undef Py_BUILD_CORE_BUILTIN
+
 /* Always enable assertions */
 #undef NDEBUG
 

configure

@@ -21258,8 +21258,8 @@ fi
 if test "$enable_test_modules" = no; then
     TEST_MODULES=no
 else
-    case $ac_sys_system in #(
-  Emscripten) :
+    case $ac_sys_system/$ac_sys_emscripten_target in #(
+  Emscripten/browser) :
     TEST_MODULES=no ;; #(
   *) :
     TEST_MODULES=yes

configure.ac

@@ -6309,8 +6309,8 @@ AC_ARG_ENABLE(test-modules,
 if test "$enable_test_modules" = no; then
     TEST_MODULES=no
 else
-    AS_CASE([$ac_sys_system],
-      [Emscripten], [TEST_MODULES=no],
+    AS_CASE([$ac_sys_system/$ac_sys_emscripten_target],
+      [Emscripten/browser], [TEST_MODULES=no],
       [TEST_MODULES=yes]
     )
 fi