[tests] serialize buck tests

Summary:
Seems like we cannot run 2 instances of Buck in parallel even when one uses
buck-out/ and the other buck-out/foo/.

Reviewed By: sblackshear

Differential Revision: D4347090

fbshipit-source-id: 7e65d2f

Makefile

@@ -138,6 +138,10 @@ $(DIRECT_TESTS:%=direct_%_clean):
 .PHONY: direct_tests
 direct_tests: $(DIRECT_TESTS:%=direct_%_test)
 
+# do not run these two tests in parallel otherwise Buck has a bad time
+build_genrule_test: build_buck_test
+build_genrule_print: build_buck_print
+
 .PHONY: print_direct_tests
 print_direct_tests: $(DIRECT_TESTS:%=direct_%_print)
 

infer/tests/build_systems/genrule/Makefile

@@ -33,6 +33,7 @@ $(ROOT_DIR)/buck-out/genruletest/gen/infer/tests/build_systems/genrule/module2/m
 	$(call silent_on_success,\
 	INFER_BIN="$(INFER_BIN)" NO_BUCKD=1 GENERATE_INFER_GENRULES=1 \
 	buck build --config project.buck_out=buck-out/genruletest --no-cache //infer/tests/build_systems/genrule/module2:module2_infer)
+	touch $@
 
 infer-out/report.json: $(ROOT_DIR)/buck-out/genruletest/gen/infer/tests/build_systems/genrule/module2/module2_infer/infer_out/report.json
 	$(MKDIR_P) infer-out