[libc] Rename libc-integration-test to libc-api-test.

[michaelrj]

LGTM

libc/docs/api_test.rst

+API Test
+=====================
+The implementation of libc-project is unique because our public C header files
+are generated using information from ground truth captured in TableGen files.
+Unit tests only exercise the internal C++ implementations and don't ensure the
+headers were generated by the build system and that the generated header files
+contain the extpected declarations and definitions. A simple solution is to have
+contributors write an integration test for each individual function as a C
+program; however, this would place a large burden on contributors and duplicates
+some effort from the unit tests.
+
+Instead we automate the generation of what we call as an API test. This API test
+ensures that public facing symbols are visible, that the header files are
+generated as expected, and that each libc function has the correct function
+prototype as specified by the standards. The API test cmake rules are located in
+``test/src/CMakeLists.txt``. The source file for the API test is generated in
+``<build directory>/projects/libc/test/src/public_api_test.cpp``

libc/docs/index.rst

.. toctree::
 
     build_system
     clang_tidy_checks
     entrypoints
     fuzzing
     ground_truth_specification
     header_generation
     implementation_standard
-    integration_test
+    api_test
     layering
     mechanics_of_public_api
     redirectors
     source_layout

libc/docs/integration_test.rst

-Integration Tests
-=====================
-The implementation of libc-project is unique because our public C header files
-are generated using information from TableGen. Unit tests only exercise the
-internal C++ implementations and don't ensure the headers were generated by the
-build system. End to end testing ensures that, after building, the produced
-library and headers are usable in the C runtime. A simple solution is to have
-contributors write an integration test for each individual function as a C
-program; however, this would place a large burden on contributors and duplicates
-some effort from the unit tests.
-
-Instead we automate the generation of integration tests by modeling it from our
-generated headers. These integration tests ensure that public facing symbols are
-visible, that header files are generated as expected, and that each libc
-function has the correct function prototype.
-
-The integration test cmake rules are located in ``test/src/CMakeLists.txt`` and
-the generated integration test lives in
-``llvm/build/projects/libc/test/src/public_integration_test.cpp``

libc/test/src/CMakeLists.txt

 # The signal API is currently disabled as signal.h is incorrect.
 # since assert uses the signal API, we disable assert also.
 # add_subdirectory(assert)
 # add_subdirectory(signal)
 add_subdirectory(stdio)
 add_subdirectory(threads)
 add_subdirectory(time)
 
-set(public_test ${CMAKE_CURRENT_BINARY_DIR}/public_integration_test.cpp)
+set(public_test ${CMAKE_CURRENT_BINARY_DIR}/public_api_test.cpp)
 
 set(entrypoints_name_list "")
 foreach(entry IN LISTS TARGET_LLVMLIBC_ENTRYPOINTS)
   get_target_property(entry_name ${entry} "ENTRYPOINT_NAME")
   list(APPEND entrypoints_name_list ${entry_name})
 endforeach()
 
 # TODO: Remove these when they are added to the TableGen.
 list(REMOVE_ITEM entrypoints_name_list "__assert_fail" "__errno_location")
 list(TRANSFORM entrypoints_name_list PREPEND "-e=")
 
 file(GLOB spec_files ${LIBC_SOURCE_DIR}/spec/*.td)
 
-# Generate integration test souce code.
+# Generate api test souce code.
 add_custom_command(
   OUTPUT ${public_test}
   COMMAND $<TARGET_FILE:libc-prototype-testgen> -o ${public_test}
           ${entrypoints_name_list}
           -I ${LIBC_SOURCE_DIR}
           ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td
 
   DEPENDS ${LIBC_SOURCE_DIR}/config/${LIBC_TARGET_OS}/api.td ${spec_files}
           libc-prototype-testgen ${TARGET_PUBLIC_HEADERS}
           llvmlibc
 )
 
 add_executable(
-  libc-integration-test
+  libc-api-test
   EXCLUDE_FROM_ALL
   ${public_test}
 )
 # Blank out default include directories to prevent accidentally including
 # system headers or our own internal headers.
 set_target_properties(
-  libc-integration-test
+  libc-api-test
   PROPERTIES
   INCLUDE_DIRECTORIES ""
 )
 # Only include we need is the include for cpp::IsSame and our generated
 # public headers.
 target_include_directories(
-  libc-integration-test BEFORE
+  libc-api-test BEFORE
   PRIVATE
     "${LIBC_SOURCE_DIR}/src/__support/CPP"
     "${LIBC_BUILD_DIR}/include"
 )
 target_compile_options(
-  libc-integration-test
+  libc-api-test
   PRIVATE
   -ffreestanding
 )
 target_link_options(
-  libc-integration-test
+  libc-api-test
   PRIVATE "-nostdlib"
 )
 set(library_files)
 foreach(library_name IN LISTS "llvmlibc")
   get_target_property(library_file ${library_name} "LIBRARY_FILE")
   list(APPEND library_files ${library_file})
 endforeach()
 
 if(COMPILER_RESOURCE_DIR AND LLVM_LIBC_ENABLE_LINTING)
   add_custom_target(
-    libc-integration-test-tidy
+    libc-api-test-tidy
     VERBATIM
     COMMAND $<TARGET_FILE:clang-tidy> --system-headers
       --checks=-*,llvmlibc-restrict-system-libc-headers
       "--extra-arg=-resource-dir=${COMPILER_RESOURCE_DIR}"
       --header-filter=.*
       --warnings-as-errors=llvmlibc-*
       "-config={CheckOptions: [{key: llvmlibc-restrict-system-libc-headers.Includes, value: '-*, linux/*, asm/*.h, asm-generic/*.h'}]}"
       --quiet
       -p ${PROJECT_BINARY_DIR}
       ${public_test}
     DEPENDS
       clang-tidy ${public_test}
   )
-  add_dependencies(libc-integration-test libc-integration-test-tidy)
+  add_dependencies(libc-api-test libc-api-test-tidy)
 endif()
 
-target_link_libraries(libc-integration-test
+target_link_libraries(libc-api-test
   PRIVATE
   ${library_files}
 )