Move templates outside the source .mk files

Templates now no longer use Make variables for substitution
but instead replace strings with their equivalent:

  template_name: Corresponds to n=template_name
  project_name:  Corresponds to $(PROJECT) or in=project_name

This allows defining templates outside of Makefiles. For
example an external plugin could define their templates
in templates/my_template.erl and then have the following
in the included Makefile:

  tpl_my_template = $(file < $(THIS)/templates/my_template.erl)

By default the created file will be in src/template_name.erl.
This can be overriden with the tplp_* variable:

  tplp_my_template = src/model/my_template.erl

Substitution is applied both to the template contents and
to its path.

In addition, attempting to overwrite an existing file when
creating a template will result in failure.

3 files changed, 51 insertions, 8 deletions

diff --git a/test/core_plugins.mk b/test/core_plugins.mk
index dcffb9a..8544945 100644
--- a/test/core_plugins.mk
+++ b/test/core_plugins.mk
@@ -194,7 +194,7 @@ core-plugins-templates: init
 	$t mkdir -p $(APP)/plugin_dep
 	$t printf "%s\n" \
 		"define tpl_test_mk" \
-		"-module(test_mk)." \
+		"-module(template_name)." \
 		"endef" > $(APP)/plugin_dep/plugins.mk
 	$t cd $(APP)/plugin_dep && \
 		git init -q && \
@@ -263,6 +263,43 @@ core-plugins-templates-apps-only: init
 	$i "Check that the file was compiled correctly"
 	$t test -f $(APP)/apps/my_app/ebin/test_mk.beam
 
+core-plugins-templates-file: init
+
+	$i "Bootstrap a new OTP library named $(APP)"
+	$t mkdir $(APP)/
+	$t cp ../erlang.mk $(APP)/
+	$t $(MAKE) -C $(APP) -f erlang.mk bootstrap-lib $v
+
+	$i "Create a local git repository with a plugin containing a template file"
+	$t mkdir -p $(APP)/plugin_dep/templates
+	$t printf "%s\n" "-module(template_name)." > $(APP)/plugin_dep/templates/test_mk.erl
+	$t echo "THIS := \$$(dir \$$(realpath \$$(lastword \$$(MAKEFILE_LIST))))" > $(APP)/plugin_dep/plugins.mk
+	$t printf "%s\n" "tpl_test_mk = \$$(file < \$$(THIS)/templates/test_mk.erl)" >> $(APP)/plugin_dep/plugins.mk
+	$t cd $(APP)/plugin_dep && \
+		git init -q && \
+		git config user.email "[email protected]" && \
+		git config user.name "test suite" && \
+		git add . && \
+		git commit -q --no-gpg-sign -m "Tests"
+
+	$i "Add dependency and plugins to the Makefile"
+	$t perl -ni.bak -e 'print;if ($$.==1) {print "DEPS = plugin_dep\ndep_plugin_dep = git file://$(abspath $(APP)/plugin_dep) master\nDEP_PLUGINS = plugin_dep\n"}' $(APP)/Makefile
+
+	$i "Run 'make list-templates' and check that it prints test_mk"
+	$t $(MAKE) --no-print-directory -C $(APP) list-templates | grep -qw test_mk
+
+	$i "Create a new file using the template"
+	$t $(MAKE) --no-print-directory -C $(APP) new t=test_mk n=test_mk $v
+
+	$i "Confirm the file exists"
+	$t test -f $(APP)/src/test_mk.erl
+
+	$i "Build the application"
+	$t $(MAKE) -C $(APP) $v
+
+	$i "Check that the file was compiled correctly"
+	$t test -f $(APP)/ebin/test_mk.beam
+
 core-plugins-test: init
 
 	$i "Bootstrap a new OTP library named $(APP)"
diff --git a/test/core_upgrade.mk b/test/core_upgrade.mk
index f165098..c9fea3d 100644
--- a/test/core_upgrade.mk
+++ b/test/core_upgrade.mk
@@ -16,8 +16,6 @@ core-upgrade-changelog: init
 	$i "Fork erlang.mk locally and set a test CHANGELOG.asciidoc"
 	$t git clone -q https://github.com/ninenines/erlang.mk $(APP)/alt-erlangmk-repo
 	$t echo "$(APP)$(APP)" > $(APP)/alt-erlangmk-repo/CHANGELOG.asciidoc
-# Since part of this functionality needs the main Makefile, copy it.
-	$t cp ../Makefile $(APP)/alt-erlangmk-repo/
 	$t (cd $(APP)/alt-erlangmk-repo && \
 		git config user.email "[email protected]" && \
 		git config user.name "test suite" && \
diff --git a/test/plugin_bootstrap.mk b/test/plugin_bootstrap.mk
index ac10ca0..aa873a8 100644
--- a/test/plugin_bootstrap.mk
+++ b/test/plugin_bootstrap.mk
@@ -303,13 +303,16 @@ bootstrap-templates: init
 	$t $(MAKE) -C $(APP) --no-print-directory new t=gen_statem n=my_statem
 	$t $(MAKE) -C $(APP) --no-print-directory new t=gen_server n=my_server
 	$t $(MAKE) -C $(APP) --no-print-directory new t=supervisor n=my_sup
-	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_http n=my_http
-	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_loop n=my_loop
-	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_rest n=my_rest
-	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_ws n=my_ws
+	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_http_h n=my_http_h
+	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_loop_h n=my_loop_h
+	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_rest_h n=my_rest_h
+	$t $(MAKE) -C $(APP) --no-print-directory new t=cowboy_websocket_h n=my_ws_h
 	$t $(MAKE) -C $(APP) --no-print-directory new t=ranch_protocol n=my_protocol
 	$t $(MAKE) -C $(APP) --no-print-directory new t=module n=my_module
 
+	$i "Confirm we can't overwrite existing files"
+	$t ! $(MAKE) -C $(APP) --no-print-directory new t=gen_server n=my_server $v
+
 # Here we disable warnings because templates contain missing behaviors.
 	$i "Build the application"
 	$t $(MAKE) -C $(APP) ERLC_OPTS=+debug_info $v
@@ -320,12 +323,17 @@ bootstrap-templates: init
 	$t test -f $(APP)/ebin/my_statem.beam
 	$t test -f $(APP)/ebin/my_server.beam
 	$t test -f $(APP)/ebin/my_sup.beam
+	$t test -f $(APP)/ebin/my_http_h.beam
+	$t test -f $(APP)/ebin/my_loop_h.beam
+	$t test -f $(APP)/ebin/my_rest_h.beam
+	$t test -f $(APP)/ebin/my_ws_h.beam
+	$t test -f $(APP)/ebin/my_protocol.beam
 	$t test -f $(APP)/ebin/my_module.beam
 
 	$i "Check that all the modules can be loaded"
 	$t $(ERL) -pa $(APP)/ebin/ -eval " \
 		ok = application:start($(APP)), \
-		{ok, Mods = [my_fsm, my_http, my_loop, my_module, my_protocol, my_rest, my_server, my_statem, my_sup, my_ws]} \
+		{ok, Mods = [my_fsm, my_http_h, my_loop_h, my_module, my_protocol, my_rest_h, my_server, my_statem, my_sup, my_ws_h]} \
 			= application:get_key($(APP), modules), \
 		[{module, M} = code:load_file(M) || M <- Mods], \
 		halt()"