[PATCH] Improve and extend tests `pluseq*.test' (on `+=' support).

[Stefano Lattarini]

Hello automakers.

The attached patch extend and impove the tests on `+=' support (for
appending to variables at automake time).

Since the "maint" branch has recently seen a commit dealing with
this feature (precisely, v1.11-222-g7a020d6 "Fix a bug in variable
concatanation with `+='."), I'd like to apply the patch to "maint"
itself, rather than only to "master".

Note that the new test `pluseq-comment-bslash.test' is xfailing,
because Automake fails to correctly strip the comments that are
affected by line continuation, as in e.g:

 VAR = quux # \
 zardoz
 VAR += foo

Here, $(VAR) will end up containing "quux zardoz foo" instead of
the expected "quux foo".

I don't know if this "bug" is worth fixing.  I'd say no, because the
above construct is IMHO an abuse to say the least, and can easily be
rewritten as:

 VAR = quux
 # zardoz
 VAR += foo

Still, having a testcase showing and exercising the limitation is
nice and useful IMHO.

Regards,
   Stefano

-*-*-*-

Improve and extend tests `pluseq*.test' (on `+=' support).

* tests/pluseq.test: Enable `errexit' shell flag.  Make grepping
of generated Makefile.in stricter.
* tests/pluseq2.test: Also run autoconf, run ./configure with
different values of conditionals, and do deeper tests by running
`make' properly.
* tests/pluseq3.test: Likewise.  Also, relax grepping of generated
Makefile.in w.r.t. whitespaces, to avoid depending too much on
automake internals.
* tests/pluseq4.test: Improve testcase description.  Make grepping
of the generated Makefile.in slighty stricter.  Extend the test a
bit.
* tests/pluseq6.test: Update testcase description.  Make grepping
of the generated Makefile.in slighty stricter.  Remove useless
AC_SUBST from configure.in and useless variable definition from
Makefile.am.  Avoid unnecessary use of a temporary variable.
Remove "threatening" comment.
* tests/pluseq-header-vars.test: New test, taking over the older
role of pluseq6.test.
* tests/pluseq7.test: Make grepping of automake error messages
stricter.  Remove "threatening" comment.
* tests/pluseq8.test: Run autoconf, ./configure and make rather
than resorting to an overly complex grepping of Makefile.in.
Add comments telling to keep it in sync with ...
* tests/pluseq12.test: ... this new test, similar to pluseq8.test,
but using leading tabs in continuation lines.
* tests/pluseq10.test: Prefer running tests from extra rules
in Makfile.am, rather then grepping `make' output.  Also run
"make distcheck".
* tests/pluseq11.test: Also run "make distcheck".
* tests/pluseq-comment.test: New test on `+=' and comments.
* tests/pluseq-comment-bslash.test: Likewise, but xfailing.
* tests/Makefile.am (TESTS, XFAIL_TESTS): Update.
---
 ChangeLog                        |   36 +++++++++++++++++++++++++
 tests/Makefile.am                |    5 +++
 tests/Makefile.in                |    5 +++
 tests/pluseq-comment-bslash.test |   54 ++++++++++++++++++++++++++++++++++++++
 tests/pluseq-comment.test        |   51 +++++++++++++++++++++++++++++++++++
 tests/pluseq-header-vars.test    |   37 ++++++++++++++++++++++++++
 tests/pluseq.test                |    9 +++++-
 tests/pluseq10.test              |   17 +++++++-----
 tests/pluseq11.test              |    2 +
 tests/pluseq12.test              |   49 ++++++++++++++++++++++++++++++++++
 tests/pluseq2.test               |   20 +++++++++++++-
 tests/pluseq3.test               |   26 ++++++++++++++---
 tests/pluseq4.test               |    8 ++++-
 tests/pluseq6.test               |   14 +++-------
 tests/pluseq7.test               |    3 +-
 tests/pluseq8.test               |   27 ++++++++++--------
 16 files changed, 322 insertions(+), 41 deletions(-)
 create mode 100755 tests/pluseq-comment-bslash.test
 create mode 100755 tests/pluseq-comment.test
 create mode 100755 tests/pluseq-header-vars.test
 create mode 100755 tests/pluseq12.test

From b55fb75a1988110e777ed405b6e0a0588c0272b9 Mon Sep 17 00:00:00 2001
From: Stefano Lattarini <address@hidden>
Date: Mon, 8 Nov 2010 17:57:08 +0100
Subject: [PATCH] Improve and extend tests `pluseq*.test' (on `+=' support).

* tests/pluseq.test: Enable `errexit' shell flag.  Make grepping
of generated Makefile.in stricter.
* tests/pluseq2.test: Also run autoconf, run ./configure with
different values of conditionals, and do deeper tests by running
`make' properly.
* tests/pluseq3.test: Likewise.  Also, relax grepping of generated
Makefile.in w.r.t. whitespaces, to avoid depending too much on
automake internals.
* tests/pluseq4.test: Improve testcase description.  Make grepping
of the generated Makefile.in slighty stricter.  Extend the test a
bit.
* tests/pluseq6.test: Update testcase description.  Make grepping
of the generated Makefile.in slighty stricter.  Remove useless
AC_SUBST from configure.in and useless variable definition from
Makefile.am.  Avoid unnecessary use of a temporary variable.
Remove "threatening" comment.
* tests/pluseq-header-vars.test: New test, taking over the older
role of pluseq6.test.
* tests/pluseq7.test: Make grepping of automake error messages
stricter.  Remove "threatening" comment.
* tests/pluseq8.test: Run autoconf, ./configure and make rather
than resorting to an overly complex grepping of Makefile.in.
Add comments telling to keep it in sync with ...
* tests/pluseq12.test: ... this new test, similar to pluseq8.test,
but using leading tabs in continuation lines.
* tests/pluseq10.test: Prefer running tests from extra rules
in Makfile.am, rather then grepping `make' output.  Also run
"make distcheck".
* tests/pluseq11.test: Also run "make distcheck".
* tests/pluseq-comment.test: New test on `+=' and comments.
* tests/pluseq-comment-bslash.test: Likewise, but xfailing.
* tests/Makefile.am (TESTS, XFAIL_TESTS): Update.
---
 ChangeLog                        |   36 +++++++++++++++++++++++++
 tests/Makefile.am                |    5 +++
 tests/Makefile.in                |    5 +++
 tests/pluseq-comment-bslash.test |   54 ++++++++++++++++++++++++++++++++++++++
 tests/pluseq-comment.test        |   51 +++++++++++++++++++++++++++++++++++
 tests/pluseq-header-vars.test    |   37 ++++++++++++++++++++++++++
 tests/pluseq.test                |    9 +++++-
 tests/pluseq10.test              |   17 +++++++-----
 tests/pluseq11.test              |    2 +
 tests/pluseq12.test              |   49 ++++++++++++++++++++++++++++++++++
 tests/pluseq2.test               |   20 +++++++++++++-
 tests/pluseq3.test               |   26 ++++++++++++++---
 tests/pluseq4.test               |    8 ++++-
 tests/pluseq6.test               |   14 +++-------
 tests/pluseq7.test               |    3 +-
 tests/pluseq8.test               |   27 ++++++++++--------
 16 files changed, 322 insertions(+), 41 deletions(-)
 create mode 100755 tests/pluseq-comment-bslash.test
 create mode 100755 tests/pluseq-comment.test
 create mode 100755 tests/pluseq-header-vars.test
 create mode 100755 tests/pluseq12.test

diff --git a/ChangeLog b/ChangeLog
index a356958..20b747b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,39 @@
+2010-11-09  Stefano Lattarini  <address@hidden>
+
+       Improve and extend tests `pluseq*.test' (on `+=' support).
+       * tests/pluseq.test: Enable `errexit' shell flag.  Make grepping
+       of generated Makefile.in stricter.
+       * tests/pluseq2.test: Also run autoconf, run ./configure with
+       different values of conditionals, and do deeper tests by running
+       `make' properly.
+       * tests/pluseq3.test: Likewise.  Also, relax grepping of generated
+       Makefile.in w.r.t. whitespaces, to avoid depending too much on
+       automake internals.
+       * tests/pluseq4.test: Improve testcase description.  Make grepping
+       of the generated Makefile.in slighty stricter.  Extend the test a
+       bit.
+       * tests/pluseq6.test: Update testcase description.  Make grepping
+       of the generated Makefile.in slighty stricter.  Remove useless
+       AC_SUBST from configure.in and useless variable definition from
+       Makefile.am.  Avoid unnecessary use of a temporary variable.
+       Remove "threatening" comment.
+       * tests/pluseq-header-vars.test: New test, taking over the older
+       role of pluseq6.test.
+       * tests/pluseq7.test: Make grepping of automake error messages
+       stricter.  Remove "threatening" comment.
+       * tests/pluseq8.test: Run autoconf, ./configure and make rather
+       than resorting to an overly complex grepping of Makefile.in.
+       Add comments telling to keep it in sync with ...
+       * tests/pluseq12.test: ... this new test, similar to pluseq8.test,
+       but using leading tabs in continuation lines.
+       * tests/pluseq10.test: Prefer running tests from extra rules
+       in Makfile.am, rather then grepping `make' output.  Also run
+       "make distcheck".
+       * tests/pluseq11.test: Also run "make distcheck".
+       * tests/pluseq-comment.test: New test on `+=' and comments.
+       * tests/pluseq-comment-bslash.test: Likewise, but xfailing.
+       * tests/Makefile.am (TESTS, XFAIL_TESTS): Update.
+
 2010-11-07  Stefano Lattarini  <address@hidden>
 
        Fix a bug in variable concatanation with `+='.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index da81c49..fd8b5cb 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -21,6 +21,7 @@ all.test \
 auxdir2.test \
 cond17.test \
 gcj6.test \
+pluseq-comment-bslash.test \
 txinfo5.test
 
 include $(srcdir)/parallel-tests.am
@@ -571,6 +572,10 @@ pluseq8.test \
 pluseq9.test \
 pluseq10.test \
 pluseq11.test \
+pluseq12.test \
+pluseq-comment.test \
+pluseq-comment-bslash.test \
+pluseq-header-vars.test \
 postproc.test \
 ppf77.test \
 pr2.test \
diff --git a/tests/Makefile.in b/tests/Makefile.in
index eb461a9..711acc8 100644
--- a/tests/Makefile.in
+++ b/tests/Makefile.in
@@ -277,6 +277,7 @@ all.test \
 auxdir2.test \
 cond17.test \
 gcj6.test \
+pluseq-comment-bslash.test \
 txinfo5.test
 
 parallel_tests = \
@@ -838,6 +839,10 @@ pluseq8.test \
 pluseq9.test \
 pluseq10.test \
 pluseq11.test \
+pluseq12.test \
+pluseq-comment.test \
+pluseq-comment-bslash.test \
+pluseq-header-vars.test \
 postproc.test \
 ppf77.test \
 pr2.test \
diff --git a/tests/pluseq-comment-bslash.test b/tests/pluseq-comment-bslash.test
new file mode 100755
index 0000000..e7e2c63
--- /dev/null
+++ b/tests/pluseq-comment-bslash.test
@@ -0,0 +1,54 @@
+#! /bin/sh
+# Copyright (C) 2010 Free Software Foundation, Inc.
+#
+# 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 2, 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/>.
+
+# Test for `+=' and comments, when line continuations *in comments*
+# are involved.
+# This test is currently failing; it's not even clear if "fixing"
+# automake to make it pass would be worthwhile.
+
+. ./defs || Exit 1
+
+set -e
+
+cat >>configure.in << 'END'
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+VAR = foo
+VAR += quux # \
+zardoz
+VAR += bar
+
+.PHONY: test
+test:
+       test x'$(VAR)' = x'foo quux bar'
+check-local: test
+END
+
+$ACLOCAL
+$AUTOMAKE
+
+grep '^VAR *=.*#' Makefile.in && Exit 1
+grep '^VAR *=.*zardoz' Makefile.in && Exit 1
+
+$AUTOCONF
+
+./configure
+$MAKE test
+$MAKE distcheck
+
+:
diff --git a/tests/pluseq-comment.test b/tests/pluseq-comment.test
new file mode 100755
index 0000000..408aa4c
--- /dev/null
+++ b/tests/pluseq-comment.test
@@ -0,0 +1,51 @@
+#! /bin/sh
+# Copyright (C) 2010 Free Software Foundation, Inc.
+#
+# 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 2, 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/>.
+
+# Test for += and comments.
+
+. ./defs || Exit 1
+
+set -e
+
+cat >>configure.in << 'END'
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+VAR = foo # foo-bad
+VAR += bar # bar-bad
+VAR += baz1 \
+baz2 # baz-bad
+VAR += quux
+
+.PHONY: test
+test:
+       test x'$(VAR)' = x'foo bar baz1 baz2 quux'
+check-local: test
+END
+
+$ACLOCAL
+$AUTOMAKE
+
+grep '^VAR *=.*#' Makefile.in && Exit 1
+grep '^VAR *=.*-bad' Makefile.in && Exit 1
+
+$AUTOCONF
+
+./configure
+$MAKE test
+$MAKE distcheck
+:
diff --git a/tests/pluseq-header-vars.test b/tests/pluseq-header-vars.test
new file mode 100755
index 0000000..aaea40e
--- /dev/null
+++ b/tests/pluseq-header-vars.test
@@ -0,0 +1,37 @@
+#! /bin/sh
+# Copyright (C) 2010 Free Software Foundation, Inc.
+#
+# 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 2, 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/>.
+
+# Test that `+=' works with standard header-vars.
+# Please update this test if definition of `pkgdatadir' is modified or
+# removed from `lib/am/header-vars.am'.
+
+. ./defs || Exit 1
+
+set -e
+
+cat > Makefile.am << 'END'
+pkgdatadir += foobar
+pkgdatadir += \
+  zardoz
+END
+
+$ACLOCAL
+$AUTOMAKE
+
+grep '^pkgdatadir *= *\$(datadir)/@PACKAGE@ foobar zardoz$' Makefile.in
+test `grep '^pkgdatadir *=' Makefile.in | wc -l` -eq 1
+
+:
diff --git a/tests/pluseq.test b/tests/pluseq.test
index 66eec8f..bf85ca8 100755
--- a/tests/pluseq.test
+++ b/tests/pluseq.test
@@ -14,10 +14,12 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Test `+=' functionality.
+# Test basic `+=' functionality.
 
 . ./defs || Exit 1
 
+set -e
+
 cat > Makefile.am << 'END'
 data_DATA = zar
 data_DATA += doz
@@ -25,6 +27,9 @@ END
 
 $ACLOCAL
 $AUTOMAKE
-$FGREP 'zar doz' Makefile.in
+
+# Check that the concatenated value hasn't been uselessly split up
+# or extended with extraneous white spaces.
+grep '^data_DATA *= *zar doz$' Makefile.in
 
 :
diff --git a/tests/pluseq10.test b/tests/pluseq10.test
index 9273415..28120c0 100755
--- a/tests/pluseq10.test
+++ b/tests/pluseq10.test
@@ -40,9 +40,14 @@ foo += b0.h \
   b1.h
 endif
 
-.PHONY: print
-print:
-       @echo BEG: $(foo) :END
+.PHONY: test
+test:
+       ## Take care of possible extra whitespaces introduced by automake
+       ## when conditionals are involved.  These extra spaces must be
+       ## considered an an implementation detail, and shouldn't cause
+       ## spurious testsuite failure.
+       test x"`echo $(foo)`" = x'0.h a0.h a1.h a2.h a3.h'
+check-local: test
 END
 
 $ACLOCAL
@@ -50,8 +55,6 @@ $AUTOCONF
 $AUTOMAKE
 
 ./configure
-$MAKE print >stdout || { cat stdout; Exit 1; }
-cat stdout
-$FGREP 'BEG: 0.h a0.h a1.h a2.h a3.h :END' stdout
-
+$MAKE test
+$MAKE distcheck
 :
diff --git a/tests/pluseq11.test b/tests/pluseq11.test
index 12ec4d7..e691042 100755
--- a/tests/pluseq11.test
+++ b/tests/pluseq11.test
@@ -40,6 +40,7 @@ FOO += baz
 .PHONY: test
 test:
        case '$(FOO)' in *\\*) exit 1;; *) exit 0;; esac
+check-local: test
 END
 
 $ACLOCAL
@@ -50,5 +51,6 @@ grep '^ *FOO *=.*\\.' Makefile.in && Exit 1
 $AUTOCONF
 ./configure
 $MAKE test
+$MAKE distcheck
 
 :
diff --git a/tests/pluseq12.test b/tests/pluseq12.test
new file mode 100755
index 0000000..5404c66
--- /dev/null
+++ b/tests/pluseq12.test
@@ -0,0 +1,49 @@
+#! /bin/sh
+# Copyright (C) 2010 Free Software Foundation, Inc.
+#
+# 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 2, 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/>.
+
+# Another `+=' test w.r.t. line continuations.  From Paul Berrevoets.
+# Keep this in sync with sister test `pluseq8.test'.
+
+. ./defs || Exit 1
+
+set -e
+
+cat >>configure.in << 'END'
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+## NOTE: leading tabs in the next lines!
+VAR = \
+       one \
+       two
+VAR += three
+
+.PHONY: test
+test:
+       test x'$(VAR)' = x'one two three'
+check-local: test
+END
+
+$ACLOCAL
+$AUTOCONF
+$AUTOMAKE
+
+./configure
+$MAKE
+$MAKE distcheck
+
+:
diff --git a/tests/pluseq2.test b/tests/pluseq2.test
index f9db345..710c10e 100755
--- a/tests/pluseq2.test
+++ b/tests/pluseq2.test
@@ -22,7 +22,8 @@
 set -e
 
 cat >> configure.in << 'END'
-AM_CONDITIONAL([CHECK], [true])
+AM_CONDITIONAL([CHECK], [test x"$cond_check" = x"yes"])
+AC_OUTPUT
 END
 
 cat > Makefile.am << 'END'
@@ -39,11 +40,28 @@ else
 data_DATA += dog
 endif
 
+.PHONY: test_CHECK_TRUE test_CHECK_FALSE
+test_CHECK_TRUE:
+       test x'$(data_DATA)' = x'zar doz'
+test_CHECK_FALSE:
+       test x'$(data_DATA)' = x'dog'
+
 END
 
 $ACLOCAL
 $AUTOMAKE
+
+# Weak grepping checks, for backward-compatibility.  Might be
+# removed if automake insternals change.
 grep 'CHECK_TRUE.*zar doz' Makefile.in
 grep 'CHECK_FALSE.*dog' Makefile.in
 
+$AUTOCONF
+
+./configure cond_check=yes
+$MAKE test_CHECK_TRUE
+
+./configure cond_check=no
+$MAKE test_CHECK_FALSE
+
 :
diff --git a/tests/pluseq3.test b/tests/pluseq3.test
index 755002c..f49892c 100755
--- a/tests/pluseq3.test
+++ b/tests/pluseq3.test
@@ -15,14 +15,15 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Another `+=' test with conditionals.
+# Test `+=' with conditionals and line wrapping.
 
 . ./defs || Exit 1
 
 set -e
 
 cat >> configure.in << 'END'
-AM_CONDITIONAL([CHECK], [true])
+AM_CONDITIONAL([CHECK], [test x"$cond_check" = x"yes"])
+AC_OUTPUT
 END
 
 cat > Makefile.am << 'END'
@@ -40,14 +41,29 @@ else
 data_DATA += dog
 endif
 
+.PHONY: test_CHECK_TRUE test_CHECK_FALSE
+test_CHECK_TRUE:
+       test x'$(data_DATA)' = 
x'zarrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr doz'
+test_CHECK_FALSE:
+       test x'$(data_DATA)' = x'dog'
+
 END
 
 $ACLOCAL
 $AUTOMAKE
 
-grep 'address@hidden@data_DATA = 
zarrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr \\$' 
Makefile.in
-grep 'address@hidden@  doz$' Makefile.in
+# Weaker grepping checks, for backward-compatibility.  Might need to
+# be adapted if automake insternals are changed.
+grep 'address@hidden@data_DATA *= 
*zarrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr \\$' 
Makefile.in
+grep 'address@hidden@[         ][      ]*doz$' Makefile.in
+grep 'address@hidden@data_DATA *= *dog$' Makefile.in
+
+$AUTOCONF
+
+./configure cond_check=yes
+$MAKE test_CHECK_TRUE
 
-grep 'address@hidden@data_DATA = dog$' Makefile.in
+./configure cond_check=no
+$MAKE test_CHECK_FALSE
 
 :
diff --git a/tests/pluseq4.test b/tests/pluseq4.test
index 744b489..7fcd60b 100755
--- a/tests/pluseq4.test
+++ b/tests/pluseq4.test
@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Yet another `+=' test.
+# Check that we can extedn AC_SUBST'd variables using `+='.
 
 . ./defs || Exit 1
 
@@ -22,15 +22,19 @@ set -e
 
 cat >> configure.in << 'END'
 AC_PROG_CC
+AC_SUBST([FOOBAR])
 END
 
 cat > Makefile.am << 'END'
 bin_PROGRAMS = foo
 CC += -Dwhatever
+FOOBAR += zardoz
 END
 
 $ACLOCAL
 $AUTOMAKE
-$FGREP '@CC@ -Dwhatever' Makefile.in
+
+grep '^CC *= address@hidden@ -Dwhatever *$' Makefile.in
+grep '^FOOBAR *= address@hidden@ zardoz *$' Makefile.in
 
 :
diff --git a/tests/pluseq6.test b/tests/pluseq6.test
index af05239..d3f8a26 100755
--- a/tests/pluseq6.test
+++ b/tests/pluseq6.test
@@ -14,27 +14,21 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Test that `+=' works with standard header-vars.
+# Test that `+=' works with $(mandir).  This test is mostly kept for
+# historical reasons, and to be safe w.r.t. backward compatibility.
 
 . ./defs || Exit 1
 
 set -e
 
-cat >> configure.in << 'END'
-AC_SUBST([ZZZ])
-END
-
-# If you do this in a real Makefile.am, I will kill you.
 cat > Makefile.am << 'END'
 mandir += foo
-zq = zzz
 END
 
 $ACLOCAL
 $AUTOMAKE
-$FGREP '@mandir@ foo' Makefile.in
 
-num=`grep '^mandir =' Makefile.in | wc -l`
-test $num -eq 1
+grep '^mandir *= address@hidden@ foo$' Makefile.in
+test `grep '^mandir *=' Makefile.in | wc -l` -eq 1
 
 :
diff --git a/tests/pluseq7.test b/tests/pluseq7.test
index 0716462..6bfefd4 100755
--- a/tests/pluseq7.test
+++ b/tests/pluseq7.test
@@ -26,7 +26,6 @@ AC_PROG_CC
 AC_PROG_RANLIB
 END
 
-# If you do this in a real Makefile.am, I will kill you.
 cat > Makefile.am << 'END'
 lib_LIBRARIES = libq.a
 libq_a_SOURCES = q.c
@@ -35,6 +34,6 @@ END
 
 $ACLOCAL
 AUTOMAKE_fails
-grep 'Makefile.am:3:.*AR' stderr
+grep '^Makefile\.am:3:.*AR.*must be set.*before.*+=' stderr
 
 :
diff --git a/tests/pluseq8.test b/tests/pluseq8.test
index 901f8b6..5f4c23d 100755
--- a/tests/pluseq8.test
+++ b/tests/pluseq8.test
@@ -15,32 +15,35 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-# Another `+=' test.  From Paul Berrevoets.
+# Another `+=' test w.r.t. line continuations.  From Paul Berrevoets.
+# Keep this in sync with sister test `pluseq13.test'.
 
 . ./defs || Exit 1
 
 set -e
 
+cat >>configure.in << 'END'
+AC_OUTPUT
+END
+
 cat > Makefile.am << 'END'
 VAR = \
     one \
     two
 VAR += three
+
+.PHONY: test
+test:
+       test x'$(VAR)' = x'one two three'
+check-local: test
 END
 
 $ACLOCAL
+$AUTOCONF
 $AUTOMAKE
 
-sed -n -e '/^VAR =/ {
-   :loop
-    p
-    n
-    t clear
-    :clear
-    s/\\$/\\/
-    t loop
-    p
-    n
-   }' Makefile.in | grep three
+./configure
+$MAKE
+$MAKE distcheck
 
 :
-- 
1.7.1