fix(odrive_native): repair the interop gate broken by the golden's espp-lib section

pc/CMakeLists.txt

@@ -18,6 +18,13 @@ set(CMAKE_CXX_STANDARD 23)
 # needed here.
 find_package(espp REQUIRED)
 
+# Every test here links the WHOLE espp::espp archive (below), so the full espp
+# package — headers AND compiled objects like Logger — is guaranteed available.
+# Declare that to the tests explicitly: pc/tests/odrive_native_golden.cpp keys
+# its espp::OdriveNative wrapper section off this (the minimal interop-harness
+# build of the same file gets no define and falls back to header detection).
+add_compile_definitions(ODRIVE_GOLDEN_HAS_ESPP_LIB=1)
+
 MACRO(GEN_TESTS curdir)
   # get test files
   FILE(GLOB tests RELATIVE ${curdir} ${curdir}/tests/*.cpp)

pc/tests/odrive_native_golden.cpp

@@ -4,9 +4,14 @@
 // round-trip, all verified against the fw-v0.5.1 reference (and proven end-to-end
 // by the serial-loopback interop harness in components/odrive_native/interop).
 //
-// Built by the pc harness against the installed espp package: odrive_native is
-// part of the x-platform espp lib, so its headers come from the espp::espp
-// target like every other test here. Exits 0 when every golden matches.
+// Built two ways:
+//   - by the pc harness against the installed espp package (full espp::espp
+//     target, so the espp::OdriveNative wrapper section below also runs);
+//   - by the interop harness (components/odrive_native/interop/run_interop.sh)
+//     with ONLY `c++ -std=c++20 -I components/odrive_native/include` — no espp
+//     lib, so the wrapper section (which needs base_component/logger/fmt and
+//     the compiled Logger) is compiled out via the __has_include guard.
+// Exits 0 when every golden matches.
 
 #include <cstdint>
 #include <cstdio>
@@ -18,7 +23,24 @@
 
 #include "detail/odrive_native_core.hpp"
 #include "detail/odrive_native_stream.hpp"
+
+// The espp::OdriveNative wrapper is only testable when the full espp package
+// (base_component + logger + fmt headers AND the compiled Logger) is on the
+// include/link path — i.e. the pc build, whose harness defines
+// ODRIVE_GOLDEN_HAS_ESPP_LIB=1 (see ../CMakeLists.txt) because it links the
+// whole espp::espp archive. When the build system says nothing (e.g. a bare
+// compile of this file), fall back to header detection; the macro is ALWAYS
+// defined to 0 or 1 so `#if` is -Wundef-clean.
+#if !defined(ODRIVE_GOLDEN_HAS_ESPP_LIB)
+#if defined(__has_include) && __has_include("base_component.hpp")
+#define ODRIVE_GOLDEN_HAS_ESPP_LIB 1
+#else
+#define ODRIVE_GOLDEN_HAS_ESPP_LIB 0
+#endif
+#endif
+#if ODRIVE_GOLDEN_HAS_ESPP_LIB
 #include "odrive_native.hpp"
+#endif
 
 using espp::detail::kProtocolVersion;
 using espp::detail::odrive_crc16;
@@ -132,7 +154,9 @@ static void golden_packet_roundtrip() {
 
 // The espp::OdriveNative wrapper (BaseComponent + the core) is what the lib
 // exposes; exercise it through the same read/write path to prove the
-// x-platform packaging end-to-end (not just the detail/ headers).
+// x-platform packaging end-to-end (not just the detail/ headers). Only built
+// when the full espp package is available (see the guard at the top).
+#if ODRIVE_GOLDEN_HAS_ESPP_LIB
 static void lib_wrapper_roundtrip() {
   std::printf("lib_wrapper_roundtrip\n");
   espp::OdriveNative dev(espp::OdriveNative::Config{.log_level = espp::Logger::Verbosity::WARN});
@@ -178,13 +202,18 @@ static void lib_wrapper_roundtrip() {
     CHECK(rb == wrote);
   }
 }
+#endif // ODRIVE_GOLDEN_HAS_ESPP_LIB
 
 int main() {
   golden_crc8();
   golden_crc16();
   golden_frame();
   golden_packet_roundtrip();
+#if ODRIVE_GOLDEN_HAS_ESPP_LIB
   lib_wrapper_roundtrip();
+#else
+  std::printf("lib_wrapper_roundtrip skipped (minimal build without the espp lib)\n");
+#endif
   if (g_failures == 0) {
     std::printf("\nODRIVE_NATIVE GOLDEN: ALL PASSED\n");
     return 0;