Fix tests CMakeLists for MIGRATE_MODULE builds

- Top-level CMakeLists.txt: Skip tests subdirectory when MIGRATE_MODULE is set
  (tests require full codebase with cross-module dependencies)
- tests/CMakeLists.txt: Add conditional checks for CodeGen and LtsTimelineClassic targets
  - Filter Grantlee tests BEFORE creating executable (fix order)
  - Exclude CodeGen tests when codegen_base target unavailable
  - Exclude LtsTimelineClassic tests when target unavailable
  - Make LtsTimelineClassic linking conditional with if(TARGET)

This enables clean BUILD_RTI=OFF builds during incremental module migration
with MIGRATE_MODULE flag.

qt6-after/qt6-migrated-legatus/CMakeLists.txt

@@ -114,8 +114,12 @@ ENDIF()
 
 ENABLE_TESTING()
 INCLUDE(CTest)
-# Add migration tests
-ADD_SUBDIRECTORY(tests)
+# Add migration tests - skip when MIGRATE_MODULE targets specific Lts modules (tests need full codebase)
+if(NOT DEFINED MIGRATE_MODULE OR MIGRATE_MODULE STREQUAL "tests")
+    ADD_SUBDIRECTORY(tests)
+else()
+    message(STATUS "MIGRATE_MODULE=${MIGRATE_MODULE} - skipping tests (need full codebase)")
+endif()
 CONFIGURE_FILE(CTestCustom.ctest ${CMAKE_BINARY_DIR}/CTestCustom.ctest COPYONLY)
 CONFIGURE_FILE(lts-cc.conf ${CMAKE_BINARY_DIR}/lts-cc.conf.distrib COPYONLY)
 

qt6-after/qt6-migrated-legatus/tests/CMakeLists.txt

@@ -36,6 +36,22 @@ if(BUILD_TESTING)
             list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_.*Grantlee.*\\.cpp")
             message(STATUS "Migration tests: Grantlee support disabled (BUILD_GRANTLEE=OFF), excluded Grantlee tests")
         endif()
+        
+        # Exclude CodeGen tests when CodeGen targets aren't available (MIGRATE_MODULE restricts scope)
+        if(NOT TARGET codegen_base)
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_StructBuilder\\.cpp")
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_SqlGenerator\\.cpp")
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_XmlReader\\.cpp")
+            message(STATUS "Migration tests: CodeGen targets not available, excluded CodeGen tests")
+        endif()
+        
+        # Exclude LtsTimelineClassic tests when LtsTimelineClassic target isn't available
+        if(NOT TARGET LtsTimelineClassic)
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_abstracttimelinemodel\\.cpp")
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_ltsclassicdatamodel\\.cpp")
+            list(FILTER EXISTING_SOURCES EXCLUDE REGEX "test_ltsclassicfilterproxymodel\\.cpp")
+            message(STATUS "Migration tests: LtsTimelineClassic target not available, excluded LtsTimelineClassic tests")
+        endif()
 
         if(NOT EXISTING_SOURCES)
             message(WARNING "No migration test sources found after filtering - skipping migration_tests target")
@@ -60,18 +76,22 @@ if(BUILD_TESTING)
             ${CMAKE_BINARY_DIR}/Lts/Common/LtsTimeline
         )
         
-        # Link against Qt6 components and LtsTimelineClassic (provides export header)
+        # Link against Qt6 components
         target_link_libraries(migration_tests PRIVATE
             Qt6::Core
             Qt6::Gui
             Qt6::Widgets
             Qt6::Test
             GTest::gtest_main
-            LtsTimelineClassic
         )
         
-        # Ensure LtsTimelineClassic is built before tests (generates export header)
-        add_dependencies(migration_tests LtsTimelineClassic)
+        # Link against LtsTimelineClassic only if it exists (may not exist with MIGRATE_MODULE)
+        if(TARGET LtsTimelineClassic)
+            target_link_libraries(migration_tests PRIVATE LtsTimelineClassic)
+            add_dependencies(migration_tests LtsTimelineClassic)
+        else()
+            message(STATUS "LtsTimelineClassic target not available - skipping link (MIGRATE_MODULE may restrict scope)")
+        endif()
         
         # Grantlee tests require BUILD_GRANTLEE=ON
         if(BUILD_GRANTLEE)