Introduce test builds and unify testing tools interface

The general idea is that erlang.mk now keeps track of what kind
of build it generated. A test build is valid for all subsequent
test target invocations. A normal build is only valid for itself
and releases.

This rework adds the ability to specify deps to eunit.

The EUNIT_DIR variable is gone in favor of a more global TEST_DIR.

The tests-ct target got renamed to ct and documented.

Many more minor changes were done during the course of testing
these changes.

3 files changed, 62 insertions, 10 deletions

diff --git a/core/core.mk b/core/core.mk
index 0d3fcf9..8622be2 100644
--- a/core/core.mk
+++ b/core/core.mk
@@ -46,8 +46,12 @@ all:: deps
 rel::
 	@echo -n
 
-clean::
+clean:: clean-crashdump
+
+clean-crashdump:
+ifneq ($(wildcard erl_crash.dump),)
 	$(gen_verbose) rm -f erl_crash.dump
+endif
 
 distclean:: clean
 
diff --git a/core/erlc.mk b/core/erlc.mk
index 8d720aa..e391da8 100644
--- a/core/erlc.mk
+++ b/core/erlc.mk
@@ -31,9 +31,15 @@ xyrl_verbose = $(xyrl_verbose_$(V))
 mib_verbose_0 = @echo " MIB   " $(filter %.bin %.mib,$(?F));
 mib_verbose = $(mib_verbose_$(V))
 
-# Core targets.
+# Targets.
 
-app:: erlc-include ebin/$(PROJECT).app
+ifeq ($(wildcard ebin/test),)
+app:: app-build
+else
+app:: clean app-build
+endif
+
+app-build: erlc-include ebin/$(PROJECT).app
 	$(eval MODULES := $(shell find ebin -type f -name \*.beam \
 		| sed "s/ebin\//'/;s/\.beam/',/" | sed '$$s/.$$//'))
 	@if [ -z "$$(grep -E '^[^%]*{modules,' src/$(PROJECT).app.src)" ]; then \
@@ -46,6 +52,11 @@ app:: erlc-include ebin/$(PROJECT).app
 		| sed "s/{id,[[:space:]]*\"git\"}/{id, \"$(GITDESCRIBE)\"}/" \
 		> ebin/$(PROJECT).app
 
+erlc-include:
+	-@if [ -d ebin/ ]; then \
+		find include/ src/ -type f -name \*.hrl -newer ebin -exec touch $(shell find src/ -type f -name "*.erl") \; 2>/dev/null || printf ''; \
+	fi
+
 define compile_erl
 	$(erlc_verbose) erlc -v $(ERLC_OPTS) -o ebin/ \
 		-pa ebin/ -I include/ $(filter-out $(ERLC_EXCLUDE_PATHS),\
@@ -85,13 +96,6 @@ endif
 
 clean:: clean-app
 
-# Extra targets.
-
-erlc-include:
-	-@if [ -d ebin/ ]; then \
-		find include/ src/ -type f -name \*.hrl -newer ebin -exec touch $(shell find src/ -type f -name "*.erl") \; 2>/dev/null || printf ''; \
-	fi
-
 clean-app:
 	$(gen_verbose) rm -rf ebin/ priv/mibs/ \
 		$(addprefix include/,$(addsuffix .hrl,$(notdir $(basename $(wildcard mibs/*.mib)))))
diff --git a/core/test.mk b/core/test.mk
new file mode 100644
index 0000000..d3f49c2
--- /dev/null
+++ b/core/test.mk
@@ -0,0 +1,44 @@
+# Copyright (c) 2015, Loïc Hoguin <[email protected]>
+# This file is part of erlang.mk and subject to the terms of the ISC License.
+
+.PHONY: test-deps test-dir test-build clean-test-dir
+
+# Configuration.
+
+TEST_DIR ?= test
+
+ALL_TEST_DEPS_DIRS = $(addprefix $(DEPS_DIR)/,$(TEST_DEPS))
+
+TEST_ERLC_OPTS ?= +debug_info +warn_export_vars +warn_shadow_vars +warn_obsolete_guard
+TEST_ERLC_OPTS += -DTEST=1
+
+# Targets.
+
+$(foreach dep,$(TEST_DEPS),$(eval $(call dep_target,$(dep))))
+
+test-deps: $(ALL_TEST_DEPS_DIRS)
+	@for dep in $(ALL_TEST_DEPS_DIRS) ; do $(MAKE) -C $$dep; done
+
+ifneq ($(strip $(TEST_DIR)),)
+test-dir:
+	$(gen_verbose) erlc -v $(TEST_ERLC_OPTS) -I include/ -o $(TEST_DIR) \
+		$(wildcard $(TEST_DIR)/*.erl $(TEST_DIR)/*/*.erl) -pa ebin/
+endif
+
+ifeq ($(wildcard ebin/test),)
+test-build: ERLC_OPTS=$(TEST_ERLC_OPTS)
+test-build: clean deps test-deps
+	@$(MAKE) --no-print-directory app-build test-dir ERLC_OPTS="$(TEST_ERLC_OPTS)"
+	$(gen_verbose) touch ebin/test
+else
+test-build: ERLC_OPTS=$(TEST_ERLC_OPTS)
+test-build: deps test-deps
+	@$(MAKE) --no-print-directory app-build test-dir ERLC_OPTS="$(TEST_ERLC_OPTS)"
+endif
+
+clean:: clean-test-dir
+
+clean-test-dir:
+ifneq ($(wildcard $(TEST_DIR)/*.beam),)
+	$(gen_verbose) rm -f $(TEST_DIR)/*.beam
+endif