more helpful error messages for debugging when a unit test fails

solenv/gbuild/CppunitTest.mk

@@ -33,6 +33,8 @@
 DBGSV_ERROR_OUT := shell
 export DBGSV_ERROR_OUT
 
+UNIT_FAILED_MSG := echo; echo "Error: a unit test failed, please do one of:"; echo; echo "export DEBUGCPPUNIT=TRUE   \# for exception catching"; echo "export GDBCPPUNITTRACE=gdb \# for interactive debugging"; echo "export VALGRIND=memcheck   \# for memory checking" ; echo "and retry."
+
 ifeq ($(strip $(DEBUGCPPUNIT)),TRUE)
 gb_CppunitTest_GDBTRACE := gdb -nx --command=$(SOLARENV)/bin/gdbtrycatchtrace-stdout -return-child-result --args
 else ifneq ($(strip $(GDBCPPUNITTRACE)),)
@@ -85,7 +87,7 @@ $(call gb_CppunitTest_get_target,%) :| $(gb_CppunitTest_CPPTESTTARGET)
 	$(call gb_Output_announce,$*,$(true),CUT,2)
 	$(call gb_Helper_abbreviate_dirs_native,\
 		mkdir -p $(dir $@) && \
-        ($(gb_CppunitTest_CPPTESTCOMMAND) $(call gb_LinkTarget_get_target,CppunitTest/$(call gb_CppunitTest_get_libfilename,$*)) $(call gb_CppunitTest__make_args,$(ARGS),$(UNO_SERVICES),$(UNO_TYPES)) $(if $(gb_CppunitTest__interactive),,> $@.log 2>&1 || (cat $@.log && false))))
+        ($(gb_CppunitTest_CPPTESTCOMMAND) $(call gb_LinkTarget_get_target,CppunitTest/$(call gb_CppunitTest_get_libfilename,$*)) $(call gb_CppunitTest__make_args,$(ARGS),$(UNO_SERVICES),$(UNO_TYPES)) $(if $(gb_CppunitTest__interactive),,> $@.log 2>&1 || (cat $@.log && $(UNIT_FAILED_MSG) && false))))
 
 define gb_CppunitTest_CppunitTest
 $(call gb_CppunitTest__CppunitTest_impl,$(1),$(call gb_CppunitTest__get_linktargetname,$(1)))