Add ERT, a tool for automated testing in Emacs Lisp.

* Makefile.in, configure.in, doc/misc/Makefile.in, doc/misc/makefile.w32-in:
Add ERT.  Make "make check" run tests in test/automated.

* doc/misc/ert.texi, lisp/emacs-lisp/ert.el, lisp/emacs-lisp/ert-x.el:
New files.

* test/automated: New directory.

4 files changed, 1388 insertions, 0 deletions

diff --git a/test/ChangeLog b/test/ChangeLog
index 3b1921c5987..695a51b7f4f 100644
--- a/test/ChangeLog
+++ b/test/ChangeLog
@@ -1,3 +1,11 @@
+2011-01-13  Christian Ohler  <ohler@gnu.org>
+
+	* automated: New directory for automated tests.
+
+	* automated/ert-tests.el, automated/ert-x-tests.el: New files.
+
+	* automated/Makefile.in: New file.
+
 2010-11-11  Stefan Monnier  <monnier@iro.umontreal.ca>
 
 	* indent/modula2.mod: New file.
diff --git a/test/automated/Makefile.in b/test/automated/Makefile.in
new file mode 100644
index 00000000000..80a853056b1
--- /dev/null
+++ b/test/automated/Makefile.in
@@ -0,0 +1,158 @@
+# Maintenance productions for the automated test directory
+# Copyright (C) 2010, 2011 Free Software Foundation, Inc.
+
+# This file is part of GNU Emacs.
+
+# GNU Emacs is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# GNU Emacs is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+SHELL = /bin/sh
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+abs_top_builddir = @abs_top_builddir@
+test = $(srcdir)
+VPATH = $(srcdir)
+lispsrc = $(top_srcdir)/lisp
+lisp = ${abs_top_builddir}/lisp
+
+# You can specify a different executable on the make command line,
+# e.g. "make EMACS=../src/emacs ...".
+
+# We sometimes change directory before running Emacs (typically when
+# building out-of-tree, we chdir to the source directory), so we need
+# to use an absolute file name.
+EMACS = ${abs_top_builddir}/src/emacs
+
+# Command line flags for Emacs.
+
+EMACSOPT = -batch --no-site-file --no-site-lisp
+
+# Extra flags to pass to the byte compiler
+BYTE_COMPILE_EXTRA_FLAGS =
+# For example to not display the undefined function warnings you can use this:
+# BYTE_COMPILE_EXTRA_FLAGS = --eval '(setq byte-compile-warnings (quote (not unresolved)))'
+# The example above is just for developers, it should not be used by default.
+
+# The actual Emacs command run in the targets below.
+emacs = EMACSLOADPATH=$(lispsrc):$(test) LC_ALL=C $(EMACS) $(EMACSOPT)
+
+# Common command to find subdirectories
+setwins=subdirs=`(find . -type d -print)`; \
+	for file in $$subdirs; do \
+	   case $$file in */.* | */.*/* | */=* ) ;; \
+		*) wins="$$wins $$file" ;; \
+	   esac; \
+        done
+
+all: test
+
+doit:
+
+
+# Files MUST be compiled one by one. If we compile several files in a
+# row (i.e., in the same instance of Emacs) we can't make sure that
+# the compilation environment is clean.  We also set the load-path of
+# the Emacs used for compilation to the current directory and its
+# subdirectories, to make sure require's and load's in the files being
+# compiled find the right files.
+
+.SUFFIXES: .elc .el
+
+# An old-fashioned suffix rule, which, according to the GNU Make manual,
+# cannot have prerequisites.
+.el.elc:
+	@echo Compiling $<
+	@$(emacs) $(BYTE_COMPILE_EXTRA_FLAGS) -f batch-byte-compile $<
+
+.PHONY: lisp-compile compile-main compile compile-always
+
+lisp-compile:
+	cd $(lisp); $(MAKE) $(MFLAGS) compile EMACS=$(EMACS)
+
+# In `compile-main' we could directly do
+#    ... | xargs $(MAKE) $(MFLAGS) EMACS="$(EMACS)"
+# and it works, but it generates a lot of messages like
+#    make[2]: « gnus/gnus-mlspl.elc » is up to date.
+# so instead, we use "xargs echo" to split the list of file into manageable
+# chunks and then use an intermediate `compile-targets' target so the
+# actual targets (the .elc files) are not mentioned as targets on the
+# make command line.
+
+
+.PHONY: compile-targets
+# TARGETS is set dynamically in the recursive call from `compile-main'.
+compile-targets: $(TARGETS)
+
+# Compile all the Elisp files that need it.  Beware: it approximates
+# `no-byte-compile', so watch out for false-positives!
+compile-main: compile-clean lisp-compile
+	@(cd $(test); $(setwins); \
+	els=`echo "$$wins " | sed -e 's|/\./|/|g' -e 's|/\. | |g' -e 's| |/*.el |g'`; \
+	for el in $$els; do \
+	  test -f $$el || continue; \
+	  test ! -f $${el}c && GREP_OPTIONS= grep '^;.*no-byte-compile: t' $$el > /dev/null && continue; \
+	  echo "$${el}c"; \
+	done | xargs echo) | \
+	while read chunk; do \
+	  $(MAKE) $(MFLAGS) compile-targets EMACS="$(EMACS)" TARGETS="$$chunk"; \
+	done
+
+.PHONY: compile-clean
+# Erase left-over .elc files that do not have a corresponding .el file.
+compile-clean:
+	@cd $(test); $(setwins); \
+	elcs=`echo "$$wins " | sed -e 's|/\./|/|g' -e 's|/\. | |g' -e 's| |/*.elc |g'`; \
+	for el in $$(echo $$elcs | sed -e 's/\.elc/\.el/g'); do \
+	  if test -f "$$el" -o \! -f "$${el}c"; then :; else \
+	    echo rm "$${el}c"; \
+	    rm "$${el}c"; \
+	  fi \
+	done
+
+# Compile all Lisp files, but don't recompile those that are up to
+# date.  Some .el files don't get compiled because they set the
+# local variable no-byte-compile.
+# Calling make recursively because suffix rule cannot have prerequisites.
+# Explicitly pass EMACS (sometimes ../src/bootstrap-emacs) to those
+# sub-makes that run rules that use it, for the sake of some non-GNU makes.
+compile: $(LOADDEFS) autoloads compile-first
+	$(MAKE) $(MFLAGS) compile-main EMACS=$(EMACS)
+
+# Compile all Lisp files.  This is like `compile' but compiles files
+# unconditionally.  Some files don't actually get compiled because they
+# set the local variable no-byte-compile.
+compile-always: doit
+	cd $(test); rm -f *.elc */*.elc */*/*.elc */*/*/*.elc
+	$(MAKE) $(MFLAGS) compile EMACS=$(EMACS)
+
+bootstrap-clean:
+	cd $(test); rm -f *.elc */*.elc */*/*.elc */*/*/*.elc
+
+distclean:
+	-rm -f ./Makefile
+
+maintainer-clean: distclean bootstrap-clean
+
+check: compile-main
+	@(cd $(test); $(setwins); \
+	pattern=`echo "$$wins " | sed -e 's|/\./|/|g' -e 's|/\. | |g' -e 's| |/*.el |g'`; \
+	for el in $$pattern; do \
+	  test -f $$el || continue; \
+	  args="$$args -l $$el"; \
+	  els="$$els $$el"; \
+	done; \
+	echo Testing $$els; \
+	$(emacs) $$args -f ert-run-tests-batch-and-exit)
+
+# Makefile ends here.
diff --git a/test/automated/ert-tests.el b/test/automated/ert-tests.el
new file mode 100644
index 00000000000..3c9e2fef0c7
--- /dev/null
+++ b/test/automated/ert-tests.el
@@ -0,0 +1,949 @@
+;;; ert-tests.el --- ERT's self-tests
+
+;; Copyright (C) 2007, 2008, 2010, 2011 Free Software Foundation, Inc.
+
+;; Author: Christian Ohler <ohler@gnu.org>
+
+;; This file is part of GNU Emacs.
+
+;; This program is free software: you can redistribute it and/or
+;; modify it under the terms of the GNU General Public License as
+;; published by the Free Software Foundation, either version 3 of the
+;; License, or (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;; General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see `http://www.gnu.org/licenses/'.
+
+;;; Commentary:
+
+;; This file is part of ERT, the Emacs Lisp Regression Testing tool.
+;; See ert.el or the texinfo manual for more details.
+
+;;; Code:
+
+(eval-when-compile
+  (require 'cl))
+(require 'ert)
+
+
+;;; Self-test that doesn't rely on ERT, for bootstrapping.
+
+;; This is used to test that bodies actually run.
+(defvar ert--test-body-was-run)
+(ert-deftest ert-test-body-runs ()
+  (setq ert--test-body-was-run t))
+
+(defun ert-self-test ()
+  "Run ERT's self-tests and make sure they actually ran."
+  (let ((window-configuration (current-window-configuration)))
+    (let ((ert--test-body-was-run nil))
+      ;; The buffer name chosen here should not compete with the default
+      ;; results buffer name for completion in `switch-to-buffer'.
+      (let ((stats (ert-run-tests-interactively "^ert-" " *ert self-tests*")))
+        (assert ert--test-body-was-run)
+        (if (zerop (ert-stats-completed-unexpected stats))
+            ;; Hide results window only when everything went well.
+            (set-window-configuration window-configuration)
+          (error "ERT self-test failed"))))))
+
+(defun ert-self-test-and-exit ()
+  "Run ERT's self-tests and exit Emacs.
+
+The exit code will be zero if the tests passed, nonzero if they
+failed or if there was a problem."
+  (unwind-protect
+      (progn
+        (ert-self-test)
+        (kill-emacs 0))
+    (unwind-protect
+        (progn
+          (message "Error running tests")
+          (backtrace))
+      (kill-emacs 1))))
+
+
+;;; Further tests are defined using ERT.
+
+(ert-deftest ert-test-nested-test-body-runs ()
+  "Test that nested test bodies run."
+  (lexical-let ((was-run nil))
+    (let ((test (make-ert-test :body (lambda ()
+                                       (setq was-run t)))))
+      (assert (not was-run))
+      (ert-run-test test)
+      (assert was-run))))
+
+
+;;; Test that pass/fail works.
+(ert-deftest ert-test-pass ()
+  (let ((test (make-ert-test :body (lambda ()))))
+    (let ((result (ert-run-test test)))
+      (assert (ert-test-passed-p result)))))
+
+(ert-deftest ert-test-fail ()
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failure message")))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (assert (ert-test-failed-p result) t)
+      (assert (equal (ert-test-result-with-condition-condition result)
+                     '(ert-test-failed "failure message"))
+              t))))
+
+(ert-deftest ert-test-fail-debug-with-condition-case ()
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failure message")))))
+    (condition-case condition
+        (progn
+          (let ((ert-debug-on-error t))
+            (ert-run-test test))
+          (assert nil))
+      ((error)
+       (assert (equal condition '(ert-test-failed "failure message")) t)))))
+
+(ert-deftest ert-test-fail-debug-with-debugger-1 ()
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failure message")))))
+    (let ((debugger (lambda (&rest debugger-args)
+                      (assert nil))))
+      (let ((ert-debug-on-error nil))
+        (ert-run-test test)))))
+
+(ert-deftest ert-test-fail-debug-with-debugger-2 ()
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failure message")))))
+    (block nil
+      (let ((debugger (lambda (&rest debugger-args)
+                        (return-from nil nil))))
+        (let ((ert-debug-on-error t))
+          (ert-run-test test))
+        (assert nil)))))
+
+(ert-deftest ert-test-fail-debug-nested-with-debugger ()
+  (let ((test (make-ert-test :body (lambda ()
+                                     (let ((ert-debug-on-error t))
+                                       (ert-fail "failure message"))))))
+    (let ((debugger (lambda (&rest debugger-args)
+                      (assert nil nil "Assertion a"))))
+      (let ((ert-debug-on-error nil))
+        (ert-run-test test))))
+  (let ((test (make-ert-test :body (lambda ()
+                                     (let ((ert-debug-on-error nil))
+                                       (ert-fail "failure message"))))))
+    (block nil
+      (let ((debugger (lambda (&rest debugger-args)
+                        (return-from nil nil))))
+        (let ((ert-debug-on-error t))
+          (ert-run-test test))
+        (assert nil nil "Assertion b")))))
+
+(ert-deftest ert-test-error ()
+  (let ((test (make-ert-test :body (lambda () (error "Error message")))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (assert (ert-test-failed-p result) t)
+      (assert (equal (ert-test-result-with-condition-condition result)
+                     '(error "Error message"))
+              t))))
+
+(ert-deftest ert-test-error-debug ()
+  (let ((test (make-ert-test :body (lambda () (error "Error message")))))
+    (condition-case condition
+        (progn
+          (let ((ert-debug-on-error t))
+            (ert-run-test test))
+          (assert nil))
+      ((error)
+       (assert (equal condition '(error "Error message")) t)))))
+
+
+;;; Test that `should' works.
+(ert-deftest ert-test-should ()
+  (let ((test (make-ert-test :body (lambda () (should nil)))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (assert (ert-test-failed-p result) t)
+      (assert (equal (ert-test-result-with-condition-condition result)
+                     '(ert-test-failed ((should nil) :form nil :value nil)))
+              t)))
+  (let ((test (make-ert-test :body (lambda () (should t)))))
+    (let ((result (ert-run-test test)))
+      (assert (ert-test-passed-p result) t))))
+
+(ert-deftest ert-test-should-value ()
+  (should (eql (should 'foo) 'foo))
+  (should (eql (should 'bar) 'bar)))
+
+(ert-deftest ert-test-should-not ()
+  (let ((test (make-ert-test :body (lambda () (should-not t)))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (assert (ert-test-failed-p result) t)
+      (assert (equal (ert-test-result-with-condition-condition result)
+                     '(ert-test-failed ((should-not t) :form t :value t)))
+              t)))
+  (let ((test (make-ert-test :body (lambda () (should-not nil)))))
+    (let ((result (ert-run-test test)))
+      (assert (ert-test-passed-p result)))))
+
+(ert-deftest ert-test-should-with-macrolet ()
+  (let ((test (make-ert-test :body (lambda ()
+                                     (macrolet ((foo () `(progn t nil)))
+                                       (should (foo)))))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (should (ert-test-failed-p result))
+      (should (equal
+               (ert-test-result-with-condition-condition result)
+               '(ert-test-failed ((should (foo))
+                                  :form (progn t nil)
+                                  :value nil)))))))
+
+(ert-deftest ert-test-should-error ()
+  ;; No error.
+  (let ((test (make-ert-test :body (lambda () (should-error (progn))))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (should (ert-test-failed-p result))
+      (should (equal (ert-test-result-with-condition-condition result)
+                     '(ert-test-failed
+                       ((should-error (progn))
+                        :form (progn)
+                        :value nil
+                        :fail-reason "did not signal an error"))))))
+  ;; A simple error.
+  (should (equal (should-error (error "Foo"))
+                 '(error "Foo")))
+  ;; Error of unexpected type.
+  (let ((test (make-ert-test :body (lambda ()
+                                     (should-error (error "Foo")
+                                                   :type 'singularity-error)))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-failed-p result))
+      (should (equal
+               (ert-test-result-with-condition-condition result)
+               '(ert-test-failed
+                 ((should-error (error "Foo") :type 'singularity-error)
+                  :form (error "Foo")
+                  :condition (error "Foo")
+                  :fail-reason
+                  "the error signalled did not have the expected type"))))))
+  ;; Error of the expected type.
+  (let* ((error nil)
+         (test (make-ert-test
+                :body (lambda ()
+                        (setq error
+                              (should-error (signal 'singularity-error nil)
+                                            :type 'singularity-error))))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-passed-p result))
+      (should (equal error '(singularity-error))))))
+
+(ert-deftest ert-test-should-error-subtypes ()
+  (should-error (signal 'singularity-error nil)
+                :type 'singularity-error
+                :exclude-subtypes t)
+  (let ((test (make-ert-test
+               :body (lambda ()
+                       (should-error (signal 'arith-error nil)
+                                     :type 'singularity-error)))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-failed-p result))
+      (should (equal
+               (ert-test-result-with-condition-condition result)
+               '(ert-test-failed
+                 ((should-error (signal 'arith-error nil)
+                                :type 'singularity-error)
+                  :form (signal arith-error nil)
+                  :condition (arith-error)
+                  :fail-reason
+                  "the error signalled did not have the expected type"))))))
+  (let ((test (make-ert-test
+               :body (lambda ()
+                       (should-error (signal 'arith-error nil)
+                                     :type 'singularity-error
+                                     :exclude-subtypes t)))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-failed-p result))
+      (should (equal
+               (ert-test-result-with-condition-condition result)
+               '(ert-test-failed
+                 ((should-error (signal 'arith-error nil)
+                                :type 'singularity-error
+                                :exclude-subtypes t)
+                  :form (signal arith-error nil)
+                  :condition (arith-error)
+                  :fail-reason
+                  "the error signalled did not have the expected type"))))))
+  (let ((test (make-ert-test
+               :body (lambda ()
+                       (should-error (signal 'singularity-error nil)
+                                     :type 'arith-error
+                                     :exclude-subtypes t)))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-failed-p result))
+      (should (equal
+               (ert-test-result-with-condition-condition result)
+               '(ert-test-failed
+                 ((should-error (signal 'singularity-error nil)
+                                :type 'arith-error
+                                :exclude-subtypes t)
+                  :form (signal singularity-error nil)
+                  :condition (singularity-error)
+                  :fail-reason
+                  "the error signalled was a subtype of the expected type")))))
+    ))
+
+(defmacro ert--test-my-list (&rest args)
+  "Don't use this.  Instead, call `list' with ARGS, it does the same thing.
+
+This macro is used to test if macroexpansion in `should' works."
+  `(list ,@args))
+
+(ert-deftest ert-test-should-failure-debugging ()
+  "Test that `should' errors contain the information we expect them to."
+  (loop for (body expected-condition) in
+        `((,(lambda () (let ((x nil)) (should x)))
+           (ert-test-failed ((should x) :form x :value nil)))
+          (,(lambda () (let ((x t)) (should-not x)))
+           (ert-test-failed ((should-not x) :form x :value t)))
+          (,(lambda () (let ((x t)) (should (not x))))
+           (ert-test-failed ((should (not x)) :form (not t) :value nil)))
+          (,(lambda () (let ((x nil)) (should-not (not x))))
+           (ert-test-failed ((should-not (not x)) :form (not nil) :value t)))
+          (,(lambda () (let ((x t) (y nil)) (should-not
+                                             (ert--test-my-list x y))))
+           (ert-test-failed
+            ((should-not (ert--test-my-list x y))
+             :form (list t nil)
+             :value (t nil))))
+          (,(lambda () (let ((x t)) (should (error "Foo"))))
+           (error "Foo")))
+        do
+        (let ((test (make-ert-test :body body)))
+          (condition-case actual-condition
+              (progn
+                (let ((ert-debug-on-error t))
+                  (ert-run-test test))
+                (assert nil))
+            ((error)
+             (should (equal actual-condition expected-condition)))))))
+
+(ert-deftest ert-test-deftest ()
+  (should (equal (macroexpand '(ert-deftest abc () "foo" :tags '(bar)))
+                 '(progn
+                    (ert-set-test 'abc
+                                  (make-ert-test :name 'abc
+                                                 :documentation "foo"
+                                                 :tags '(bar)
+                                                 :body (lambda ())))
+                    (push '(ert-deftest . abc) current-load-list)
+                    'abc)))
+  (should (equal (macroexpand '(ert-deftest def ()
+                                 :expected-result ':passed))
+                 '(progn
+                    (ert-set-test 'def
+                                  (make-ert-test :name 'def
+                                                 :expected-result-type ':passed
+                                                 :body (lambda ())))
+                    (push '(ert-deftest . def) current-load-list)
+                    'def)))
+  ;; :documentation keyword is forbidden
+  (should-error (macroexpand '(ert-deftest ghi ()
+                                :documentation "foo"))))
+
+(ert-deftest ert-test-record-backtrace ()
+  (let ((test (make-ert-test :body (lambda () (ert-fail "foo")))))
+    (let ((result (ert-run-test test)))
+      (should (ert-test-failed-p result))
+      (with-temp-buffer
+        (ert--print-backtrace (ert-test-failed-backtrace result))
+        (goto-char (point-min))
+        (end-of-line)
+        (let ((first-line (buffer-substring-no-properties (point-min) (point))))
+          (should (equal first-line "  signal(ert-test-failed (\"foo\"))")))))))
+
+(ert-deftest ert-test-messages ()
+  :tags '(:causes-redisplay)
+  (let* ((message-string "Test message")
+         (messages-buffer (get-buffer-create "*Messages*"))
+         (test (make-ert-test :body (lambda () (message "%s" message-string)))))
+    (with-current-buffer messages-buffer
+      (let ((result (ert-run-test test)))
+        (should (equal (concat message-string "\n")
+                       (ert-test-result-messages result)))))))
+
+(ert-deftest ert-test-running-tests ()
+  (let ((outer-test (ert-get-test 'ert-test-running-tests)))
+    (should (equal (ert-running-test) outer-test))
+    (let (test1 test2 test3)
+      (setq test1 (make-ert-test
+                   :name "1"
+                   :body (lambda ()
+                           (should (equal (ert-running-test) outer-test))
+                           (should (equal ert--running-tests
+                                          (list test1 test2 test3
+                                                outer-test)))))
+            test2 (make-ert-test
+                   :name "2"
+                   :body (lambda ()
+                           (should (equal (ert-running-test) outer-test))
+                           (should (equal ert--running-tests
+                                          (list test3 test2 outer-test)))
+                           (ert-run-test test1)))
+            test3 (make-ert-test
+                   :name "3"
+                   :body (lambda ()
+                           (should (equal (ert-running-test) outer-test))
+                           (should (equal ert--running-tests
+                                          (list test3 outer-test)))
+                           (ert-run-test test2))))
+      (should (ert-test-passed-p (ert-run-test test3))))))
+
+(ert-deftest ert-test-test-result-expected-p ()
+  "Test `ert-test-result-expected-p' and (implicitly) `ert-test-result-type-p'."
+  ;; passing test
+  (let ((test (make-ert-test :body (lambda ()))))
+    (should (ert-test-result-expected-p test (ert-run-test test))))
+  ;; unexpected failure
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failed")))))
+    (should-not (ert-test-result-expected-p test (ert-run-test test))))
+  ;; expected failure
+  (let ((test (make-ert-test :body (lambda () (ert-fail "failed"))
+                             :expected-result-type ':failed)))
+    (should (ert-test-result-expected-p test (ert-run-test test))))
+  ;; `not' expected type
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(not :failed))))
+    (should (ert-test-result-expected-p test (ert-run-test test))))
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(not :passed))))
+    (should-not (ert-test-result-expected-p test (ert-run-test test))))
+  ;; `and' expected type
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(and :passed :failed))))
+    (should-not (ert-test-result-expected-p test (ert-run-test test))))
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(and :passed
+                                                         (not :failed)))))
+    (should (ert-test-result-expected-p test (ert-run-test test))))
+  ;; `or' expected type
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(or (and :passed :failed)
+                                                        :passed))))
+    (should (ert-test-result-expected-p test (ert-run-test test))))
+  (let ((test (make-ert-test :body (lambda ())
+                             :expected-result-type '(or (and :passed :failed)
+                                                        nil (not t)))))
+    (should-not (ert-test-result-expected-p test (ert-run-test test)))))
+
+;;; Test `ert-select-tests'.
+(ert-deftest ert-test-select-regexp ()
+  (should (equal (ert-select-tests "^ert-test-select-regexp$" t)
+                 (list (ert-get-test 'ert-test-select-regexp)))))
+
+(ert-deftest ert-test-test-boundp ()
+  (should (ert-test-boundp 'ert-test-test-boundp))
+  (should-not (ert-test-boundp (make-symbol "ert-not-a-test"))))
+
+(ert-deftest ert-test-select-member ()
+  (should (equal (ert-select-tests '(member ert-test-select-member) t)
+                 (list (ert-get-test 'ert-test-select-member)))))
+
+(ert-deftest ert-test-select-test ()
+  (should (equal (ert-select-tests (ert-get-test 'ert-test-select-test) t)
+                 (list (ert-get-test 'ert-test-select-test)))))
+
+(ert-deftest ert-test-select-symbol ()
+  (should (equal (ert-select-tests 'ert-test-select-symbol t)
+                 (list (ert-get-test 'ert-test-select-symbol)))))
+
+(ert-deftest ert-test-select-and ()
+  (let ((test (make-ert-test
+               :name nil
+               :body nil
+               :most-recent-result (make-ert-test-failed
+                                    :condition nil
+                                    :backtrace nil
+                                    :infos nil))))
+    (should (equal (ert-select-tests `(and (member ,test) :failed) t)
+                   (list test)))))
+
+(ert-deftest ert-test-select-tag ()
+  (let ((test (make-ert-test
+               :name nil
+               :body nil
+               :tags '(a b))))
+    (should (equal (ert-select-tests `(tag a) (list test)) (list test)))
+    (should (equal (ert-select-tests `(tag b) (list test)) (list test)))
+    (should (equal (ert-select-tests `(tag c) (list test)) '()))))
+
+
+;;; Tests for utility functions.
+(ert-deftest ert-test-proper-list-p ()
+  (should (ert--proper-list-p '()))
+  (should (ert--proper-list-p '(1)))
+  (should (ert--proper-list-p '(1 2)))
+  (should (ert--proper-list-p '(1 2 3)))
+  (should (ert--proper-list-p '(1 2 3 4)))
+  (should (not (ert--proper-list-p 'a)))
+  (should (not (ert--proper-list-p '(1 . a))))
+  (should (not (ert--proper-list-p '(1 2 . a))))
+  (should (not (ert--proper-list-p '(1 2 3 . a))))
+  (should (not (ert--proper-list-p '(1 2 3 4 . a))))
+  (let ((a (list 1)))
+    (setf (cdr (last a)) a)
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2)))
+    (setf (cdr (last a)) a)
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3)))
+    (setf (cdr (last a)) a)
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3 4)))
+    (setf (cdr (last a)) a)
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2)))
+    (setf (cdr (last a)) (cdr a))
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3)))
+    (setf (cdr (last a)) (cdr a))
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3 4)))
+    (setf (cdr (last a)) (cdr a))
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3)))
+    (setf (cdr (last a)) (cddr a))
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3 4)))
+    (setf (cdr (last a)) (cddr a))
+    (should (not (ert--proper-list-p a))))
+  (let ((a (list 1 2 3 4)))
+    (setf (cdr (last a)) (cdddr a))
+    (should (not (ert--proper-list-p a)))))
+
+(ert-deftest ert-test-parse-keys-and-body ()
+  (should (equal (ert--parse-keys-and-body '(foo)) '(nil (foo))))
+  (should (equal (ert--parse-keys-and-body '(:bar foo)) '((:bar foo) nil)))
+  (should (equal (ert--parse-keys-and-body '(:bar foo a (b)))
+                 '((:bar foo) (a (b)))))
+  (should (equal (ert--parse-keys-and-body '(:bar foo :a (b)))
+                 '((:bar foo :a (b)) nil)))
+  (should (equal (ert--parse-keys-and-body '(bar foo :a (b)))
+                 '(nil (bar foo :a (b)))))
+  (should-error (ert--parse-keys-and-body '(:bar foo :a))))
+
+
+(ert-deftest ert-test-run-tests-interactively ()
+  :tags '(:causes-redisplay)
+  (let ((passing-test (make-ert-test :name 'passing-test
+                                     :body (lambda () (ert-pass))))
+        (failing-test (make-ert-test :name 'failing-test
+                                     :body (lambda () (ert-fail
+                                                       "failure message")))))
+    (let ((ert-debug-on-error nil))
+      (let* ((buffer-name (generate-new-buffer-name " *ert-test-run-tests*"))
+             (messages nil)
+             (mock-message-fn
+              (lambda (format-string &rest args)
+                (push (apply #'format format-string args) messages))))
+        (save-window-excursion
+          (unwind-protect
+              (let ((case-fold-search nil))
+                (ert-run-tests-interactively
+                 `(member ,passing-test ,failing-test) buffer-name
+                 mock-message-fn)
+                (should (equal messages `(,(concat
+                                            "Ran 2 tests, 1 results were "
+                                            "as expected, 1 unexpected"))))
+                (with-current-buffer buffer-name
+                  (goto-char (point-min))
+                  (should (equal
+                           (buffer-substring (point-min)
+                                             (save-excursion
+                                               (forward-line 4)
+                                               (point)))
+                           (concat
+                            "Selector: (member <passing-test> <failing-test>)\n"
+                            "Passed: 1\n"
+                            "Failed: 1 (1 unexpected)\n"
+                            "Total:  2/2\n")))))
+            (when (get-buffer buffer-name)
+              (kill-buffer buffer-name))))))))
+
+(ert-deftest ert-test-special-operator-p ()
+  (should (ert--special-operator-p 'if))
+  (should-not (ert--special-operator-p 'car))
+  (should-not (ert--special-operator-p 'ert--special-operator-p))
+  (let ((b (ert--gensym)))
+    (should-not (ert--special-operator-p b))
+    (fset b 'if)
+    (should (ert--special-operator-p b))))
+
+(ert-deftest ert-test-list-of-should-forms ()
+  (let ((test (make-ert-test :body (lambda ()
+                                     (should t)
+                                     (should (null '()))
+                                     (should nil)
+                                     (should t)))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (should (equal (ert-test-result-should-forms result)
+                     '(((should t) :form t :value t)
+                       ((should (null '())) :form (null nil) :value t)
+                       ((should nil) :form nil :value nil)))))))
+
+(ert-deftest ert-test-list-of-should-forms-observers-should-not-stack ()
+  (let ((test (make-ert-test
+               :body (lambda ()
+                       (let ((test2 (make-ert-test
+                                     :body (lambda ()
+                                             (should t)))))
+                         (let ((result (ert-run-test test2)))
+                           (should (ert-test-passed-p result))))))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (should (ert-test-passed-p result))
+      (should (eql (length (ert-test-result-should-forms result))
+                   1)))))
+
+(ert-deftest ert-test-list-of-should-forms-no-deep-copy ()
+  (let ((test (make-ert-test :body (lambda ()
+                                     (let ((obj (list 'a)))
+                                       (should (equal obj '(a)))
+                                       (setf (car obj) 'b)
+                                       (should (equal obj '(b))))))))
+    (let ((result (let ((ert-debug-on-error nil))
+                    (ert-run-test test))))
+      (should (ert-test-passed-p result))
+      (should (equal (ert-test-result-should-forms result)
+                     '(((should (equal obj '(a))) :form (equal (b) (a)) :value t
+                        :explanation nil)
+                       ((should (equal obj '(b))) :form (equal (b) (b)) :value t
+                        :explanation nil)
+                       ))))))
+
+(ert-deftest ert-test-remprop ()
+  (let ((x (ert--gensym)))
+    (should (equal (symbol-plist x) '()))
+    ;; Remove nonexistent property on empty plist.
+    (ert--remprop x 'b)
+    (should (equal (symbol-plist x) '()))
+    (put x 'a 1)
+    (should (equal (symbol-plist x) '(a 1)))
+    ;; Remove nonexistent property on nonempty plist.
+    (ert--remprop x 'b)
+    (should (equal (symbol-plist x) '(a 1)))
+    (put x 'b 2)
+    (put x 'c 3)
+    (put x 'd 4)
+    (should (equal (symbol-plist x) '(a 1 b 2 c 3 d 4)))
+    ;; Remove property that is neither first nor last.
+    (ert--remprop x 'c)
+    (should (equal (symbol-plist x) '(a 1 b 2 d 4)))
+    ;; Remove last property from a plist of length >1.
+    (ert--remprop x 'd)
+    (should (equal (symbol-plist x) '(a 1 b 2)))
+    ;; Remove first property from a plist of length >1.
+    (ert--remprop x 'a)
+    (should (equal (symbol-plist x) '(b 2)))
+    ;; Remove property when there is only one.
+    (ert--remprop x 'b)
+    (should (equal (symbol-plist x) '()))))
+
+(ert-deftest ert-test-remove-if-not ()
+  (let ((list (list 'a 'b 'c 'd))
+        (i 0))
+    (let ((result (ert--remove-if-not (lambda (x)
+                                        (should (eql x (nth i list)))
+                                        (incf i)
+                                        (member i '(2 3)))
+                                      list)))
+      (should (equal i 4))
+      (should (equal result '(b c)))
+      (should (equal list '(a b c d)))))
+  (should (equal '()
+                 (ert--remove-if-not (lambda (x) (should nil)) '()))))
+
+(ert-deftest ert-test-remove* ()
+  (let ((list (list 'a 'b 'c 'd))
+        (key-index 0)
+        (test-index 0))
+    (let ((result
+           (ert--remove* 'foo list
+                         :key (lambda (x)
+                                (should (eql x (nth key-index list)))
+                                (prog1
+                                    (list key-index x)
+                                  (incf key-index)))
+                         :test
+                         (lambda (a b)
+                           (should (eql a 'foo))
+                           (should (equal b (list test-index
+                                                  (nth test-index list))))
+                           (incf test-index)
+                           (member test-index '(2 3))))))
+      (should (equal key-index 4))
+      (should (equal test-index 4))
+      (should (equal result '(a d)))
+      (should (equal list '(a b c d)))))
+  (let ((x (cons nil nil))
+        (y (cons nil nil)))
+    (should (equal (ert--remove* x (list x y))
+                   ;; or (list x), since we use `equal' -- the
+                   ;; important thing is that only one element got
+                   ;; removed, this proves that the default test is
+                   ;; `eql', not `equal'
+                   (list y)))))
+
+
+(ert-deftest ert-test-set-functions ()
+  (let ((c1 (cons nil nil))
+        (c2 (cons nil nil))
+        (sym (make-symbol "a")))
+    (let ((e '())
+          (a (list 'a 'b sym nil "" "x" c1 c2))
+          (b (list c1 'y 'b sym 'x)))
+      (should (equal (ert--set-difference e e) e))
+      (should (equal (ert--set-difference a e) a))
+      (should (equal (ert--set-difference e a) e))
+      (should (equal (ert--set-difference a a) e))
+      (should (equal (ert--set-difference b e) b))
+      (should (equal (ert--set-difference e b) e))
+      (should (equal (ert--set-difference b b) e))
+      (should (equal (ert--set-difference a b) (list 'a nil "" "x" c2)))
+      (should (equal (ert--set-difference b a) (list 'y 'x)))
+
+      ;; We aren't testing whether this is really using `eq' rather than `eql'.
+      (should (equal (ert--set-difference-eq e e) e))
+      (should (equal (ert--set-difference-eq a e) a))
+      (should (equal (ert--set-difference-eq e a) e))
+      (should (equal (ert--set-difference-eq a a) e))
+      (should (equal (ert--set-difference-eq b e) b))
+      (should (equal (ert--set-difference-eq e b) e))
+      (should (equal (ert--set-difference-eq b b) e))
+      (should (equal (ert--set-difference-eq a b) (list 'a nil "" "x" c2)))
+      (should (equal (ert--set-difference-eq b a) (list 'y 'x)))
+
+      (should (equal (ert--union e e) e))
+      (should (equal (ert--union a e) a))
+      (should (equal (ert--union e a) a))
+      (should (equal (ert--union a a) a))
+      (should (equal (ert--union b e) b))
+      (should (equal (ert--union e b) b))
+      (should (equal (ert--union b b) b))
+      (should (equal (ert--union a b) (list 'a 'b sym nil "" "x" c1 c2 'y 'x)))
+      (should (equal (ert--union b a) (list c1 'y 'b sym 'x 'a nil "" "x" c2)))
+
+      (should (equal (ert--intersection e e) e))
+      (should (equal (ert--intersection a e) e))
+      (should (equal (ert--intersection e a) e))
+      (should (equal (ert--intersection a a) a))
+      (should (equal (ert--intersection b e) e))
+      (should (equal (ert--intersection e b) e))
+      (should (equal (ert--intersection b b) b))
+      (should (equal (ert--intersection a b) (list 'b sym c1)))
+      (should (equal (ert--intersection b a) (list c1 'b sym))))))
+
+(ert-deftest ert-test-gensym ()
+  ;; Since the expansion of `should' calls `ert--gensym' and thus has a
+  ;; side-effect on `ert--gensym-counter', we have to make sure all
+  ;; macros in our test body are expanded before we rebind
+  ;; `ert--gensym-counter' and run the body.  Otherwise, the test would
+  ;; fail if run interpreted.
+  (let ((body (byte-compile
+               '(lambda ()
+                  (should (equal (symbol-name (ert--gensym)) "G0"))
+                  (should (equal (symbol-name (ert--gensym)) "G1"))
+                  (should (equal (symbol-name (ert--gensym)) "G2"))
+                  (should (equal (symbol-name (ert--gensym "foo")) "foo3"))
+                  (should (equal (symbol-name (ert--gensym "bar")) "bar4"))
+                  (should (equal ert--gensym-counter 5))))))
+    (let ((ert--gensym-counter 0))
+      (funcall body))))
+
+(ert-deftest ert-test-coerce-to-vector ()
+  (let* ((a (vector))
+         (b (vector 1 a 3))
+         (c (list))
+         (d (list b a)))
+    (should (eql (ert--coerce-to-vector a) a))
+    (should (eql (ert--coerce-to-vector b) b))
+    (should (equal (ert--coerce-to-vector c) (vector)))
+    (should (equal (ert--coerce-to-vector d) (vector b a)))))
+
+(ert-deftest ert-test-string-position ()
+  (should (eql (ert--string-position ?x "") nil))
+  (should (eql (ert--string-position ?a "abc") 0))
+  (should (eql (ert--string-position ?b "abc") 1))
+  (should (eql (ert--string-position ?c "abc") 2))
+  (should (eql (ert--string-position ?d "abc") nil))
+  (should (eql (ert--string-position ?A "abc") nil)))
+
+(ert-deftest ert-test-mismatch ()
+  (should (eql (ert--mismatch "" "") nil))
+  (should (eql (ert--mismatch "" "a") 0))
+  (should (eql (ert--mismatch "a" "a") nil))
+  (should (eql (ert--mismatch "ab" "a") 1))
+  (should (eql (ert--mismatch "Aa" "aA") 0))
+  (should (eql (ert--mismatch '(a b c) '(a b d)) 2)))
+
+(ert-deftest ert-test-string-first-line ()
+  (should (equal (ert--string-first-line "") ""))
+  (should (equal (ert--string-first-line "abc") "abc"))
+  (should (equal (ert--string-first-line "abc\n") "abc"))
+  (should (equal (ert--string-first-line "foo\nbar") "foo"))
+  (should (equal (ert--string-first-line " foo\nbar\nbaz\n") " foo")))
+
+(ert-deftest ert-test-explain-not-equal ()
+  (should (equal (ert--explain-not-equal nil 'foo)
+                 '(different-atoms nil foo)))
+  (should (equal (ert--explain-not-equal '(a a) '(a b))
+                 '(list-elt 1 (different-atoms a b))))
+  (should (equal (ert--explain-not-equal '(1 48) '(1 49))
+                 '(list-elt 1 (different-atoms (48 "#x30" "?0")
+                                               (49 "#x31" "?1")))))
+  (should (equal (ert--explain-not-equal 'nil '(a))
+                 '(different-types nil (a))))
+  (should (equal (ert--explain-not-equal '(a b c) '(a b c d))
+                 '(proper-lists-of-different-length 3 4 (a b c) (a b c d)
+                                                    first-mismatch-at 3)))
+  (let ((sym (make-symbol "a")))
+    (should (equal (ert--explain-not-equal 'a sym)
+                   `(different-symbols-with-the-same-name a ,sym)))))
+
+(ert-deftest ert-test-explain-not-equal-improper-list ()
+  (should (equal (ert--explain-not-equal '(a . b) '(a . c))
+                 '(cdr (different-atoms b c)))))
+
+(ert-deftest ert-test-significant-plist-keys ()
+  (should (equal (ert--significant-plist-keys '()) '()))
+  (should (equal (ert--significant-plist-keys '(a b c d e f c g p q r nil s t))
+                 '(a c e p s))))
+
+(ert-deftest ert-test-plist-difference-explanation ()
+  (should (equal (ert--plist-difference-explanation
+                  '(a b c nil) '(a b))
+                 nil))
+  (should (equal (ert--plist-difference-explanation
+                  '(a b c t) '(a b))
+                 '(different-properties-for-key c (different-atoms t nil))))
+  (should (equal (ert--plist-difference-explanation
+                  '(a b c t) '(c nil a b))
+                 '(different-properties-for-key c (different-atoms t nil))))
+  (should (equal (ert--plist-difference-explanation
+                  '(a b c (foo . bar)) '(c (foo . baz) a b))
+                 '(different-properties-for-key c
+                                                (cdr
+                                                 (different-atoms bar baz))))))
+
+(ert-deftest ert-test-abbreviate-string ()
+  (should (equal (ert--abbreviate-string "foo" 4 nil) "foo"))
+  (should (equal (ert--abbreviate-string "foo" 3 nil) "foo"))
+  (should (equal (ert--abbreviate-string "foo" 3 nil) "foo"))
+  (should (equal (ert--abbreviate-string "foo" 2 nil) "fo"))
+  (should (equal (ert--abbreviate-string "foo" 1 nil) "f"))
+  (should (equal (ert--abbreviate-string "foo" 0 nil) ""))
+  (should (equal (ert--abbreviate-string "bar" 4 t) "bar"))
+  (should (equal (ert--abbreviate-string "bar" 3 t) "bar"))
+  (should (equal (ert--abbreviate-string "bar" 3 t) "bar"))
+  (should (equal (ert--abbreviate-string "bar" 2 t) "ar"))
+  (should (equal (ert--abbreviate-string "bar" 1 t) "r"))
+  (should (equal (ert--abbreviate-string "bar" 0 t) "")))
+
+(ert-deftest ert-test-explain-not-equal-string-properties ()
+  (should
+   (equal (ert--explain-not-equal-including-properties #("foo" 0 1 (a b))
+                                                       "foo")
+          '(char 0 "f"
+                 (different-properties-for-key a (different-atoms b nil))
+                 context-before ""
+                 context-after "oo")))
+  (should (equal (ert--explain-not-equal-including-properties
+                  #("foo" 1 3 (a b))
+                  #("goo" 0 1 (c d)))
+                 '(array-elt 0 (different-atoms (?f "#x66" "?f")
+                                                (?g "#x67" "?g")))))
+  (should
+   (equal (ert--explain-not-equal-including-properties
+           #("foo" 0 1 (a b c d) 1 3 (a b))
+           #("foo" 0 1 (c d a b) 1 2 (a foo)))
+          '(char 1 "o" (different-properties-for-key a (different-atoms b foo))
+                 context-before "f" context-after "o"))))
+
+(ert-deftest ert-test-equal-including-properties ()
+  (should (equal-including-properties "foo" "foo"))
+  (should (ert-equal-including-properties "foo" "foo"))
+
+  (should (equal-including-properties #("foo" 0 3 (a b))
+                                      (propertize "foo" 'a 'b)))
+  (should (ert-equal-including-properties #("foo" 0 3 (a b))
+                                          (propertize "foo" 'a 'b)))
+
+  (should (equal-including-properties #("foo" 0 3 (a b c d))
+                                      (propertize "foo" 'a 'b 'c 'd)))
+  (should (ert-equal-including-properties #("foo" 0 3 (a b c d))
+                                          (propertize "foo" 'a 'b 'c 'd)))
+
+  (should-not (equal-including-properties #("foo" 0 3 (a b c e))
+                                          (propertize "foo" 'a 'b 'c 'd)))
+  (should-not (ert-equal-including-properties #("foo" 0 3 (a b c e))
+                                              (propertize "foo" 'a 'b 'c 'd)))
+
+  ;; This is bug 6581.
+  (should-not (equal-including-properties #("foo" 0 3 (a (t)))
+                                          (propertize "foo" 'a (list t))))
+  (should (ert-equal-including-properties #("foo" 0 3 (a (t)))
+                                          (propertize "foo" 'a (list t)))))
+
+(ert-deftest ert-test-stats-set-test-and-result ()
+  (let* ((test-1 (make-ert-test :name 'test-1
+                                :body (lambda () nil)))
+         (test-2 (make-ert-test :name 'test-2
+                                :body (lambda () nil)))
+         (test-3 (make-ert-test :name 'test-2
+                                :body (lambda () nil)))
+         (stats (ert--make-stats (list test-1 test-2) 't))
+         (failed (make-ert-test-failed :condition nil
+                                       :backtrace nil
+                                       :infos nil)))
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 0 (ert-stats-completed stats)))
+    (should (eql 0 (ert-stats-completed-expected stats)))
+    (should (eql 0 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 0 test-1 (make-ert-test-passed))
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 1 (ert-stats-completed stats)))
+    (should (eql 1 (ert-stats-completed-expected stats)))
+    (should (eql 0 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 0 test-1 failed)
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 1 (ert-stats-completed stats)))
+    (should (eql 0 (ert-stats-completed-expected stats)))
+    (should (eql 1 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 0 test-1 nil)
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 0 (ert-stats-completed stats)))
+    (should (eql 0 (ert-stats-completed-expected stats)))
+    (should (eql 0 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 0 test-3 failed)
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 1 (ert-stats-completed stats)))
+    (should (eql 0 (ert-stats-completed-expected stats)))
+    (should (eql 1 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 1 test-2 (make-ert-test-passed))
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 2 (ert-stats-completed stats)))
+    (should (eql 1 (ert-stats-completed-expected stats)))
+    (should (eql 1 (ert-stats-completed-unexpected stats)))
+    (ert--stats-set-test-and-result stats 0 test-1 (make-ert-test-passed))
+    (should (eql 2 (ert-stats-total stats)))
+    (should (eql 2 (ert-stats-completed stats)))
+    (should (eql 2 (ert-stats-completed-expected stats)))
+    (should (eql 0 (ert-stats-completed-unexpected stats)))))
+
+
+(provide 'ert-tests)
+
+;;; ert-tests.el ends here
diff --git a/test/automated/ert-x-tests.el b/test/automated/ert-x-tests.el
new file mode 100644
index 00000000000..80fff40d86a
--- /dev/null
+++ b/test/automated/ert-x-tests.el
@@ -0,0 +1,273 @@
+;;; ert-x-tests.el --- Tests for ert-x.el
+
+;; Copyright (C) 2008, 2010, 2011 Free Software Foundation, Inc.
+
+;; Author: Phil Hagelberg
+;; Author: Christian Ohler <ohler@gnu.org>
+
+;; This file is part of GNU Emacs.
+
+;; This program is free software: you can redistribute it and/or
+;; modify it under the terms of the GNU General Public License as
+;; published by the Free Software Foundation, either version 3 of the
+;; License, or (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;; General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see `http://www.gnu.org/licenses/'.
+
+;;; Commentary:
+
+;; This file is part of ERT, the Emacs Lisp Regression Testing tool.
+;; See ert.el or the texinfo manual for more details.
+
+;;; Code:
+
+(eval-when-compile
+  (require 'cl))
+(require 'ert)
+(require 'ert-x)
+
+;;; Utilities
+
+(ert-deftest ert-test-buffer-string-reindented ()
+  (ert-with-test-buffer (:name "well-indented")
+    (insert (concat "(hello (world\n"
+                    "        'elisp)\n"))
+    (emacs-lisp-mode)
+    (should (equal (ert-buffer-string-reindented) (buffer-string))))
+  (ert-with-test-buffer (:name "badly-indented")
+    (insert (concat "(hello\n"
+                    "       world)"))
+    (emacs-lisp-mode)
+    (should-not (equal (ert-buffer-string-reindented) (buffer-string)))))
+
+(defun ert--hash-table-to-alist (table)
+  (let ((accu nil))
+    (maphash (lambda (key value)
+	       (push (cons key value) accu))
+	     table)
+    (nreverse accu)))
+
+(ert-deftest ert-test-test-buffers ()
+  (let (buffer-1
+        buffer-2)
+    (let ((test-1
+           (make-ert-test
+            :name 'test-1
+            :body (lambda ()
+                    (ert-with-test-buffer (:name "foo")
+                      (should (string-match
+                               "[*]Test buffer (ert-test-test-buffers): foo[*]"
+                               (buffer-name)))
+                      (setq buffer-1 (current-buffer))))))
+          (test-2
+           (make-ert-test
+            :name 'test-2
+            :body (lambda ()
+                    (ert-with-test-buffer (:name "bar")
+                      (should (string-match
+                               "[*]Test buffer (ert-test-test-buffers): bar[*]"
+                               (buffer-name)))
+                      (setq buffer-2 (current-buffer))
+                      (ert-fail "fail for test"))))))
+      (let ((ert--test-buffers (make-hash-table :weakness t)))
+        (ert-run-tests `(member ,test-1 ,test-2) #'ignore)
+        (should (equal (ert--hash-table-to-alist ert--test-buffers)
+                       `((,buffer-2 . t))))
+        (should-not (buffer-live-p buffer-1))
+        (should (buffer-live-p buffer-2))))))
+
+
+(ert-deftest ert-filter-string ()
+  (should (equal (ert-filter-string "foo bar baz" "quux")
+                 "foo bar baz"))
+  (should (equal (ert-filter-string "foo bar baz" "bar")
+                 "foo  baz")))
+
+(ert-deftest ert-propertized-string ()
+  (should (ert-equal-including-properties
+           (ert-propertized-string "a" '(a b) "b" '(c t) "cd")
+           #("abcd" 1 2 (a b) 2 4 (c t))))
+  (should (ert-equal-including-properties
+           (ert-propertized-string "foo " '(face italic) "bar" " baz" nil
+                                   " quux")
+           #("foo bar baz quux" 4 11 (face italic)))))
+
+
+;;; Tests for ERT itself that require test features from ert-x.el.
+
+(ert-deftest ert-test-run-tests-interactively-2 ()
+  :tags '(:causes-redisplay)
+  (let ((passing-test (make-ert-test :name 'passing-test
+                                     :body (lambda () (ert-pass))))
+        (failing-test (make-ert-test :name 'failing-test
+                                     :body (lambda ()
+                                             (ert-info ((propertize "foo\nbar"
+                                                                    'a 'b))
+					      (ert-fail
+					       "failure message"))))))
+    (let ((ert-debug-on-error nil))
+      (let* ((buffer-name (generate-new-buffer-name "*ert-test-run-tests*"))
+             (messages nil)
+             (mock-message-fn
+              (lambda (format-string &rest args)
+                (push (apply #'format format-string args) messages))))
+        (flet ((expected-string (with-font-lock-p)
+                 (ert-propertized-string
+                  "Selector: (member <passing-test> <failing-test>)\n"
+                  "Passed: 1\n"
+                  "Failed: 1 (1 unexpected)\n"
+                  "Total:  2/2\n\n"
+                  "Started at:\n"
+                  "Finished.\n"
+                  "Finished at:\n\n"
+                  `(category ,(button-category-symbol
+                               'ert--results-progress-bar-button)
+                             button (t)
+                             face ,(if with-font-lock-p
+                                       'ert-test-result-unexpected
+                                     'button))
+                  ".F" nil "\n\n"
+                  `(category ,(button-category-symbol
+                               'ert--results-expand-collapse-button)
+                             button (t)
+                             face ,(if with-font-lock-p
+                                       'ert-test-result-unexpected
+                                     'button))
+                  "F" nil " "
+                  `(category ,(button-category-symbol
+                               'ert--test-name-button)
+                             button (t)
+                             ert-test-name failing-test)
+                  "failing-test"
+                  nil "\n    Info: " '(a b) "foo\n"
+                  nil "          " '(a b) "bar"
+                  nil "\n    (ert-test-failed \"failure message\")\n\n\n"
+                  )))
+        (save-window-excursion
+          (unwind-protect
+              (let ((case-fold-search nil))
+                (ert-run-tests-interactively
+                 `(member ,passing-test ,failing-test) buffer-name
+                 mock-message-fn)
+                (should (equal messages `(,(concat
+                                            "Ran 2 tests, 1 results were "
+                                            "as expected, 1 unexpected"))))
+                (with-current-buffer buffer-name
+                  (font-lock-mode 0)
+                  (should (ert-equal-including-properties
+                           (ert-filter-string (buffer-string)
+                                              '("Started at:\\(.*\\)$" 1)
+                                              '("Finished at:\\(.*\\)$" 1))
+                           (expected-string nil)))
+                  ;; `font-lock-mode' only works if interactive, so
+                  ;; pretend we are.
+                  (let ((noninteractive nil))
+                    (font-lock-mode 1))
+                  (should (ert-equal-including-properties
+                           (ert-filter-string (buffer-string)
+                                              '("Started at:\\(.*\\)$" 1)
+                                              '("Finished at:\\(.*\\)$" 1))
+                           (expected-string t)))))
+            (when (get-buffer buffer-name)
+              (kill-buffer buffer-name)))))))))
+
+(ert-deftest ert-test-describe-test ()
+  "Tests `ert-describe-test'."
+  (save-window-excursion
+    (ert-with-buffer-renamed ("*Help*")
+      (if (< emacs-major-version 24)
+          (should (equal (should-error (ert-describe-test 'ert-describe-test))
+                         '(error "Requires Emacs 24")))
+        (ert-describe-test 'ert-test-describe-test)
+        (with-current-buffer "*Help*"
+          (let ((case-fold-search nil))
+            (should (string-match (concat
+                                   "\\`ert-test-describe-test is a test"
+                                   " defined in `ert-x-tests.elc?'\\.\n\n"
+                                   "Tests `ert-describe-test'\\.\n\\'")
+                                  (buffer-string)))))))))
+
+(ert-deftest ert-test-message-log-truncation ()
+  :tags '(:causes-redisplay)
+  (let ((test (make-ert-test
+               :body (lambda ()
+                       ;; Emacs would combine messages if we
+                       ;; generate the same message multiple
+                       ;; times.
+                       (message "a")
+                       (message "b")
+                       (message "c")
+                       (message "d")))))
+    (let (result)
+      (ert-with-buffer-renamed ("*Messages*")
+        (let ((message-log-max 2))
+          (setq result (ert-run-test test)))
+        (should (equal (with-current-buffer "*Messages*"
+                         (buffer-string))
+                       "c\nd\n")))
+      (should (equal (ert-test-result-messages result) "a\nb\nc\nd\n")))))
+
+(ert-deftest ert-test-builtin-message-log-flushing ()
+  "This test attempts to demonstrate that there is no way to
+force immediate truncation of the *Messages* buffer from Lisp
+\(and hence justifies the existence of
+`ert--force-message-log-buffer-truncation'\): The only way that
+came to my mind was \(message \"\"\), which doesn't have the
+desired effect."
+  :tags '(:causes-redisplay)
+  (ert-with-buffer-renamed ("*Messages*")
+    (with-current-buffer "*Messages*"
+      (should (equal (buffer-string) ""))
+      ;; We used to get sporadic failures in this test that involved
+      ;; a spurious newline at the beginning of the buffer, before
+      ;; the first message.  Below, we print a message and erase the
+      ;; buffer since this seems to eliminate the sporadic failures.
+      (message "foo")
+      (erase-buffer)
+      (should (equal (buffer-string) ""))
+      (let ((message-log-max 2))
+        (let ((message-log-max t))
+          (loop for i below 4 do
+                (message "%s" i))
+          (should (equal (buffer-string) "0\n1\n2\n3\n")))
+        (should (equal (buffer-string) "0\n1\n2\n3\n"))
+        (message "")
+        (should (equal (buffer-string) "0\n1\n2\n3\n"))
+        (message "Test message")
+        (should (equal (buffer-string) "3\nTest message\n"))))))
+
+(ert-deftest ert-test-force-message-log-buffer-truncation ()
+  :tags '(:causes-redisplay)
+  (labels ((body ()
+             (loop for i below 3 do
+                   (message "%s" i)))
+           ;; Uses the implicit messages buffer truncation implemented
+           ;; in Emacs' C core.
+           (c (x)
+             (ert-with-buffer-renamed ("*Messages*")
+               (let ((message-log-max x))
+                 (body))
+               (with-current-buffer "*Messages*"
+                 (buffer-string))))
+           ;; Uses our lisp reimplementation.
+           (lisp (x)
+             (ert-with-buffer-renamed ("*Messages*")
+               (let ((message-log-max t))
+                 (body))
+               (let ((message-log-max x))
+                 (ert--force-message-log-buffer-truncation))
+               (with-current-buffer "*Messages*"
+                 (buffer-string)))))
+    (loop for x in '(0 1 2 3 4 t) do
+          (should (equal (c x) (lisp x))))))
+
+
+(provide 'ert-x-tests)
+
+;;; ert-x-tests.el ends here