cmake fixes

CMakeLists.txt

@@ -24,6 +24,16 @@ if (NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
     "MinSizeRel" "RelWithDebInfo")
 endif()
 
+# ---------------------------------------------------------------------------
+# Check whether all dependencies are present
+# ---------------------------------------------------------------------------
+
+if (NOT IS_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/ext/robin_map/include")
+  message(FATAL_ERROR "The nanobind dependencies are missing! "
+    "You probably did not clone the project with --recursive. It is possible to recover "
+    "by invoking\n$ git submodule update --init --recursive")
+endif()
+
 # ---------------------------------------------------------------------------
 # Compile with a few more compiler warnings turned on
 # ---------------------------------------------------------------------------

tests/CMakeLists.txt

@@ -32,18 +32,5 @@ if (NOT (CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR) OR MSVC)
       COMMAND ${CMAKE_COMMAND} -E copy_if_different ${IN_FILE} ${OUT_DIR})
   endforeach()
 
-  if (WIN32)
-    set(OUT_FILE ${OUT_DIR}/nanobind.dll)
-  elseif(APPLE)
-    set(OUT_FILE ${OUT_DIR}/libnanobind.dylib)
-  else()
-    set(OUT_FILE ${OUT_DIR}/libnanobind.so)
-  endif()
-
-  add_custom_command(
-    DEPENDS nanobind TARGET OUTPUT ${OUT_FILE}
-    COMMAND ${CMAKE_COMMAND} -E copy_if_different $<TARGET_FILE:nanobind> ${OUT_DIR})
-  set(TEST_FILES_OUT ${TEST_FILES_OUT} ${OUT_FILE})
-
   add_custom_target(copy-tests ALL DEPENDS ${TEST_FILES_OUT})
 endif()