Additional changes for "make check-expensive"

* CONTRIBUTE : Encourage use of ":tags '(:expensive-test)".
Explain make target `check-expensive'.

* etc/NEWS: Mention new make target `check-expensive'.

* test/automated/Makefile.in (check-doit): New target.
(check, check-expensive): Use it.

CONTRIBUTE

@@ -251,12 +251,20 @@ Emacs uses ERT, Emacs Lisp Regression Testing, for testing.  See (info
 "(ert)") or https://www.gnu.org/software/emacs/manual/html_node/ert/
 for more information on writing and running tests.
 
+If your test lasts longer than some few seconds, mark it in its
+`ert-deftest' definition with ":tags '(:expensive-test)".
+
 To run tests on the entire Emacs tree, run "make check" from the
 top-level directory.  Most tests are in the directory
 "test/automated".  From the "test/automated" directory, run "make
 <filename>" to run the tests for <filename>.el(c).  See
 "test/automated/Makefile" for more information.
 
+Tests which are tagged ":expensive-test" are enabled additionally, if
+you run "make check-expensive" from the top-level directory.  "make
+<filename>" as mentioned above incorporates expensive tests for
+<filename>.el(c).
+
 ** Understanding Emacs Internals.
 
 The best way to understand Emacs Internals is to read the code,

etc/NEWS

@@ -96,6 +96,10 @@ so if you want to use it, you can always take a copy from an older Emacs.
 Various resolutions are available as etc/images/icons/hicolor/*/apps/emacs.png.
 The old Emacs logo icons are available as `emacs23.png' in the same location.
 
+** New make target `check-expensive' to run additional tests.
+This includes all tests which run via "make check", plus additional
+tests which take more time to perform.
+
 
 * Startup Changes in Emacs 25.1
 

test/automated/Makefile.in

@@ -87,9 +87,9 @@ WRITE_LOG = > $@ 2>&1 || { stat=ERROR; cat $@; }; echo $$stat: $@
 ## to change this; bug#17848 - if that gets done, this can be simplified).
 ##
 ## Beware: it approximates 'no-byte-compile', so watch out for false-positives!
-SELECTOR_DEFAULT=(not (tag :expensive-test))
+SELECTOR_DEFAULT=(quote (not (tag :expensive-test)))
 SELECTOR_EXPENSIVE=nil
-SELECTOR=${SELECTOR_DEFAULT}
+SELECTOR=
 %.log: ${srcdir}/%.el
 	@if grep '^;.*no-byte-compile: t' $< > /dev/null; then \
 	  loadfile=$<; \
@@ -100,7 +100,7 @@ SELECTOR=${SELECTOR_DEFAULT}
 	echo Testing $$loadfile; \
 	stat=OK ; \
 	$(emacs) -l ert -l $$loadfile \
-	  --eval "(ert-run-tests-batch-and-exit '${SELECTOR})" ${WRITE_LOG}
+	  --eval "(ert-run-tests-batch-and-exit ${SELECTOR})" ${WRITE_LOG}
 
 ELFILES = $(sort $(wildcard ${srcdir}/*.el))
 LOGFILES = $(patsubst %.el,%.log,$(notdir ${ELFILES}))
@@ -121,16 +121,20 @@ endef
 
 $(foreach test,${TESTS},$(eval $(call test_template,${test})))
 
-
+## Rerun default tests.
-## Re-run all the tests every time.
 check:
-	-@for f in *.log; do test ! -f $$f || mv $$f $$f~; done
+	@${MAKE} check-doit SELECTOR="${SELECTOR_DEFAULT}"
-	@${MAKE} check-maybe
 
 ## Rerun also expensive tests.
 .PHONY: check-expensive
 check-expensive:
-	@${MAKE} check SELECTOR=${SELECTOR_EXPENSIVE}
+	@${MAKE} check-doit SELECTOR="${SELECTOR_EXPENSIVE}"
+
+## Re-run all the tests every time.
+.PHONY: check-doit
+check-doit:
+	-@for f in *.log; do test ! -f $$f || mv $$f $$f~; done
+	@${MAKE} check-maybe
 
 ## Only re-run tests whose .log is older than the test.
 .PHONY: check-maybe