build: (fixes #789) add examples as dependencies of example-as-test suites

build-support/custom-modules/ns3-module-macros.cmake

@@ -237,6 +237,26 @@ function(build_lib)
     )
   endif()
 
+  # Build lib examples if requested
+  set(examples_before ${ns3-execs-clean})
+  foreach(example_folder example;examples)
+    if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${example_folder})
+      if(${ENABLE_EXAMPLES})
+        if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${example_folder}/CMakeLists.txt)
+          add_subdirectory(${example_folder})
+        endif()
+      endif()
+      scan_python_examples(${CMAKE_CURRENT_SOURCE_DIR}/${example_folder})
+    endif()
+  endforeach()
+  set(module_examples ${ns3-execs-clean})
+
+  # Filter only module examples
+  foreach(example ${examples_before})
+    list(REMOVE_ITEM module_examples ${example})
+  endforeach()
+  unset(examples_before)
+
   # Check if the module tests should be built
   set(filtered_in ON)
   if(NS3_FILTER_MODULE_EXAMPLES_AND_TESTS)
@@ -291,21 +311,24 @@ function(build_lib)
       if(${PRECOMPILE_HEADERS_ENABLED} AND (NOT ${BLIB_IGNORE_PCH}))
         target_precompile_headers(${test${BLIB_LIBNAME}} REUSE_FROM stdlib_pch)
       endif()
+
+      # Add dependency between tests and examples used as tests
+      if(${ENABLE_EXAMPLES})
+        foreach(source_file ${BLIB_TEST_SOURCES})
+          file(READ ${source_file} source_file_contents)
+          foreach(example_as_test ${module_examples})
+            string(FIND "${source_file_contents}" "${example_as_test}"
+                        is_sub_string
+            )
+            if(NOT (${is_sub_string} EQUAL -1))
+              add_dependencies(test-runner-examples-as-tests ${example_as_test})
+            endif()
+          endforeach()
+        endforeach()
+      endif()
     endif()
   endif()
 
-  # Build lib examples if requested
-  foreach(example_folder example;examples)
-    if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${example_folder})
-      if(${ENABLE_EXAMPLES})
-        if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${example_folder}/CMakeLists.txt)
-          add_subdirectory(${example_folder})
-        endif()
-      endif()
-      scan_python_examples(${CMAKE_CURRENT_SOURCE_DIR}/${example_folder})
-    endif()
-  endforeach()
-
   # Handle package export
   install(
     TARGETS ${lib${BLIB_LIBNAME}}

build-support/macros-and-definitions.cmake

@@ -293,6 +293,7 @@ macro(clear_global_cached_variables)
   unset(ns3-contrib-libs CACHE)
   unset(ns3-example-folders CACHE)
   unset(ns3-execs CACHE)
+  unset(ns3-execs-clean CACHE)
   unset(ns3-execs-py CACHE)
   unset(ns3-external-libs CACHE)
   unset(ns3-headers-to-module-map CACHE)
@@ -306,6 +307,7 @@ macro(clear_global_cached_variables)
     ns3-contrib-libs
     ns3-example-folders
     ns3-execs
+    ns3-execs-clean
     ns3-execs-py
     ns3-external-libs
     ns3-headers-to-module-map
@@ -888,6 +890,7 @@ macro(process_options)
   endif()
 
   if(${ENABLE_TESTS})
+    add_custom_target(test-runner-examples-as-tests)
     add_custom_target(all-test-targets)
 
     # Create a custom target to run test.py --no-build Target is also used to
@@ -1382,6 +1385,10 @@ function(set_runtime_outputdirectory target_name output_directory target_prefix)
   set(ns3-execs "${output_directory}${ns3-exec-outputname};${ns3-execs}"
       CACHE INTERNAL "list of c++ executables"
   )
+  set(ns3-execs-clean "${target_prefix}${target_name};${ns3-execs-clean}"
+      CACHE INTERNAL
+            "list of c++ executables without version prefix and build suffix"
+  )
 
   set_target_properties(
     ${target_prefix}${target_name}

utils/CMakeLists.txt

@@ -30,6 +30,7 @@ if(${ENABLE_TESTS} AND (test IN_LIST libs_to_build))
   set_runtime_outputdirectory(
     test-runner ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/utils/ ""
   )
+  add_dependencies(test-runner test-runner-examples-as-tests)
   add_dependencies(all-test-targets test-runner)
 endif()