[test] test the correct version of toplevel.cmo

Summary:
There are 2 possible places where to find toplevel.cmo:
- infer/_build/infer/toplevel.cmo, built by `make toplevel`
- infer/_build/test/infer/toplevel.cmo, built by `make test`

The test loading and running toplevel.cmo would give priority to the non-test
version of toplevel.cmo, which might be stale because `make test` doesn't
rebuild it.

This diff makes sure we use the test version of toplevel.cmo in `make test`.

Reviewed By: akotulski

Differential Revision: D4960550

fbshipit-source-id: 9c817ba

Makefile

@@ -289,7 +289,8 @@ toplevel: clang_plugin
 .PHONY: inferScriptMode_test
 inferScriptMode_test: test_build
 	$(QUIET)$(call silent_on_success,Testing infer OCaml REPL,\
-	 INFER_REPL_BINARY=ocaml $(SCRIPT_DIR)/infer_repl $(INFER_DIR)/tests/repl/infer_batch_script.ml)
+	INFER_REPL_BINARY=ocaml TOPLEVEL_DIR=$(BUILD_DIR)/test/infer $(SCRIPT_DIR)/infer_repl \
+	  $(INFER_DIR)/tests/repl/infer_batch_script.ml)
 
 .PHONY: checkCopyright
 checkCopyright:

scripts/infer_repl

@@ -2,14 +2,11 @@
 
 SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
-# _build/infer is first so that it takes precedence. This way if someone explicitly builds the
-# toplevel (`make toplevel`) they get the expected version of infer. The _build/test toplevel is
-# built during `make test` which is probably run less often, hence why it doesn't take
-# precedence. Of course this cannot be perfect so caution is advised.
-TOPLEVEL_INCLUDES=(
-    -I "$SCRIPT_DIR"/../infer/_build/infer
-    -I "$SCRIPT_DIR"/../infer/_build/test/infer
-)
+# where to find toplevel.cmo, can be overridden
+TOPLEVEL_DIR=${TOPLEVEL_DIR:-"$SCRIPT_DIR"/../infer/_build/infer}
+
+# how to load the toplevel; can be overridden (with "ocaml" for example)
+INFER_REPL_BINARY=${INFER_REPL_BINARY:-"utop"}
 
 # to build new toplevel, run `make toplevel`
 # -init option is used only in interactive mode
@@ -20,9 +17,4 @@ TOPLEVEL_INCLUDES=(
 #       so they can be located anywhere and still find toplevel_init
 #       file. In interactive mode $SCRIPT_DIR isn't needed
 
-# by default utop is used, pass `INFER_REPL_BINARY` to change the toplevel
-# binary (to `ocaml` for example)
-if [ -z "$INFER_REPL_BINARY" ]; then
-  INFER_REPL_BINARY="utop"
-fi
-$INFER_REPL_BINARY -init $SCRIPT_DIR/toplevel_init ${TOPLEVEL_INCLUDES[@]} -I $SCRIPT_DIR $@
+"$INFER_REPL_BINARY" -init "$SCRIPT_DIR"/toplevel_init -I "$TOPLEVEL_DIR" -I "$SCRIPT_DIR" $@