I think this will fix building simulator tests?

etc/makefiles/arduino-cli.mk

@@ -1,5 +1,4 @@
-mkfile_path := $(abspath $(lastword $(MAKEFILE_LIST)))
-mkfile_dir := $(dir $(mkfile_path))
+mkfile_dir := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
 
 KALEIDOSCOPE_DIR ?= $(abspath $(mkfile_dir)/../..)
 KALEIDOSCOPE_BIN_DIR ?= $(KALEIDOSCOPE_DIR)/bin

testing/makefiles/testcase.mk

@@ -1,15 +1,18 @@
 top_dir         := $(dir $(lastword ${MAKEFILE_LIST}))../..
 
-include $(top_dir)/etc/makefiles/arduino-cli.mk
 
 build_dir := ${top_dir}/_build/${testcase}
 
+
 LIB_DIR := ${build_dir}/lib
 OBJ_DIR := ${build_dir}/obj
 BIN_DIR	:= ${build_dir}/bin
 
 COMMON_LIB_DIR	:= ${top_dir}/_build/lib
 
+include $(top_dir)/etc/makefiles/arduino-cli.mk
+
+
 SRC_DIR	:= test
 
 SKETCH_FILE=$(wildcard *.ino)
@@ -29,6 +32,7 @@ TEST_FILES += $(SRC_DIR)/generated-testcase.cpp
 endif
 endif
 
+.DEFAULT_GOAL := build
 
 TEST_OBJS=$(patsubst $(SRC_DIR)/%.cpp,${OBJ_DIR}/%.o,$(TEST_FILES))