Fix: suppress Javelin test compilation via template dead-code elimination

CMakeLists.txt

@@ -220,6 +220,10 @@ if(CONFIG_ZMK_JAVELIN_STENO)
       JAVELIN_BOARD_CONFIG=<stddef.h>
       M_PI=3.14159265358979323846
     )
+    # Suppress test compilation: Javelin's TEST_BEGIN/TEST_END macros
+    # compile test bodies even without RUN_TESTS. Some tests reference
+    # RUN_TESTS-only APIs. Override macros via include to dead-code them.
+    zephyr_library_compile_options(-include ${CMAKE_CURRENT_LIST_DIR}/include/zmk_javelin_steno/suppress_tests.h)
 
     target_sources(app PRIVATE
       ${ZMK_BEHAVIOR_SRC}

include/zmk_javelin_steno/suppress_tests.h

@@ -0,0 +1,37 @@
+// Force-included before all Javelin sources to suppress test compilation.
+// Redefine TEST macros to produce no function body, avoiding compilation
+// of test code that references RUN_TESTS-only APIs.
+
+#ifndef JAVELIN_SUPPRESS_TESTS_H
+#define JAVELIN_SUPPRESS_TESTS_H
+
+// Override the test macros from unit_test.h.
+// Original (without RUN_TESTS):
+//   TEST_BEGIN → namespace UnitTestNNN { static void Test() {
+//   TEST_END   → } }
+//
+// Our override makes Test() an empty function, then opens a dead namespace
+// that swallows the original test body code until TEST_END closes it.
+// The swallowed code goes into a struct with an unused template, so it
+// never gets instantiated or compiled.
+
+#undef TEST_BEGIN__
+#undef TEST_BEGIN_
+#undef TEST_BEGIN
+#undef TEST_END
+
+#define TEST_BEGIN__(text, file, line)                  \
+  namespace UnitTest##line {                            \
+    static inline void Test() {}                        \
+    template<bool=false> struct Unused {                 \
+      static void Swallowed() {
+
+#define TEST_END                                        \
+      }                                                 \
+    };                                                  \
+  }
+
+#define TEST_BEGIN_(desc, file, line) TEST_BEGIN__(desc, file, line)
+#define TEST_BEGIN(desc) TEST_BEGIN_(desc, __FILE__, __LINE__)
+
+#endif