Don't require a leading underscore in PYBIND11_NONLIMITEDAPI_SUFFIX.

Author: adalisk-emikhaylov

source/non_limited_api/CMakeLists.txt

@@ -21,7 +21,7 @@ endif()
 option(PYBIND11_NONLIMITEDAPI_BUILD_STUBS "Build the stubs library." ON)
 
 set(PYBIND11_NONLIMITEDAPI_PYTHON_MIN_VERSION_HEX "" CACHE STRING "A hex Python version to bake into the library, e.g. `0x030800f0` for 3.8 (the `f0` suffix is always there and means a release version).")
-set(PYBIND11_NONLIMITEDAPI_SUFFIX "" CACHE STRING "A custom suffix to append to the built library name. Should normally be `[_AppName][_X.Y]`, where X,Y is the Python version.")
+set(PYBIND11_NONLIMITEDAPI_SUFFIX "" CACHE STRING "A custom suffix to append to the built library name.")
 set(PYBIND11_NONLIMITEDAPI_LIBRARY_OUTPUT_DIR "" CACHE PATH "Replaces the library installation path for the shim.")
 
 include(GNUInstallDirs)
@@ -68,7 +68,13 @@ endif()
 if (PYBIND11_NONLIMITEDAPI_PYTHON_MIN_VERSION_HEX STREQUAL "")
   message("Not building shim because no Python version is specified.")
 else()
-  set(PYBIND11_NONLIMITEDAPI_LIBNAME "pybind11nonlimitedapi${PYBIND11_NONLIMITEDAPI_SUFFIX}_${Python_VERSION_MAJOR}.${Python_VERSION_MINOR}")
+  if (NOT "${PYBIND11_NONLIMITEDAPI_SUFFIX}" STREQUAL "")
+    set(PYBIND11_NONLIMITEDAPI_UNDERSCORE "_")
+  else()
+    set(PYBIND11_NONLIMITEDAPI_UNDERSCORE "")
+  endif()
+
+  set(PYBIND11_NONLIMITEDAPI_LIBNAME "pybind11nonlimitedapi${PYBIND11_NONLIMITEDAPI_UNDERSCORE}${PYBIND11_NONLIMITEDAPI_SUFFIX}_${Python_VERSION_MAJOR}.${Python_VERSION_MINOR}")
   project(${PYBIND11_NONLIMITEDAPI_LIBNAME})
   add_library(${PROJECT_NAME} SHARED non_limited_api.cpp)