build: add configure option to disable gnulib tests

The gnulib testsuite is relatively stable - the only times it is
likely to have a test change from pass to fail is on a gnulib
submodule update or a major system change (such as moving from
Fedora 18 to 19, or other large change to libc).  While it is an
important test for end users on arbitrary machines (to make sure
that the portability glue works for their machine), it mostly
wastes time for development testing (as most developers aren't
making any of the major changes that would cause gnulib tests
to alter behavior).  Thus, it pays to make the tests optional
at configure time, defaulting to off for development, on for
tarballs, with autobuilders requesting it to be on.  It also
helps to allow a make-time override, via VIR_TEST_EXPENSIVE=[01]
(much the way automake sets up V=[01] for overriding the configure
time default of how verbose to be).

Automake has some pretty hard-coded magic with regards to the
TESTS variable; I had quite a job figuring out how to keep
'make distcheck' passing regardless of the configure option
setting in use, while still disabling the tests at runtime
when I did not configure them on and did not use the override
variable.  Thankfully, we require GNU make, which lets me
hide some information from Automake's magic handling of TESTS.

* bootstrap.conf (bootstrap_epilogue): Munge gnulib test variable.
* configure.ac (--enable-expensive-tests): Add new enable switch.
(VIR_TEST_EXPENSIVE_DEFAULT, WITH_EXPENSIVE_TESTS): Set new
witnesses.
* gnulib/tests/Makefile.am (TESTS): Make tests conditional on
configure settings and the VIR_TEST_EXPENSIVE variable.
* tests/Makefile.am (TESTS_ENVIRONMENT): Expose VIR_TEST_EXPENSIVE
to all tests.
* autobuild.sh: Enable all tests during autobuilds.
* libvirt.spec.in (%configure): Likewise.
* mingw-libvirt.spec.in (%mingw_configure): Likewise.
* docs/hacking.html.in: Document the option.
* HACKING: Regenerate.

Signed-off-by: Eric Blake <eblake@redhat.com>

HACKING

@@ -107,6 +107,15 @@ and run the tests:
 Valgrind <http://valgrind.org/> is a test that checks for memory management
 issues, such as leaks or use of uninitialized variables.
 
+Some tests are skipped by default in a development environment, based on the
+time they take in comparison to the likelihood that those tests will turn up
+problems during incremental builds. These tests default to being run when when
+building from a tarball or with the configure option --enable-expensive-tests;
+you can also force a one-time toggle of these tests by setting
+VIR_TEST_EXPENSIVE to 0 or 1 at make time, as in:
+
+  make check VIR_TEST_EXPENSIVE=1
+
 If you encounter any failing tests, the VIR_TEST_DEBUG environment variable
 may provide extra information to debug the failures. Larger values of
 VIR_TEST_DEBUG may provide larger amounts of information:

autobuild.sh

@@ -18,6 +18,7 @@ cd build
 # Run with options not normally exercised by the rpm build, for
 # more complete code coverage.
 ../autogen.sh --prefix="$AUTOBUILD_INSTALL_ROOT" \
+  --enable-expensive-tests \
   --enable-test-coverage \
   --disable-nls \
   --enable-werror \
@@ -76,6 +77,7 @@ if test -x /usr/bin/i686-w64-mingw32-gcc ; then
     --build=$(uname -m)-w64-linux \
     --host=i686-w64-mingw32 \
     --prefix="$AUTOBUILD_INSTALL_ROOT/i686-w64-mingw32/sys-root/mingw" \
+    --enable-expensive-tests \
     --enable-werror \
     --without-libvirtd \
     --without-python
@@ -96,6 +98,7 @@ if test -x /usr/bin/x86_64-w64-mingw32-gcc ; then
     --build=$(uname -m)-w64-linux \
     --host=x86_64-w64-mingw32 \
     --prefix="$AUTOBUILD_INSTALL_ROOT/x86_64-w64-mingw32/sys-root/mingw" \
+    --enable-expensive-tests \
     --enable-werror \
     --without-libvirtd \
     --without-python

bootstrap.conf

@@ -244,9 +244,10 @@ gnulib_extra_files="
 bootstrap_epilogue()
 {
   # Change paths in gnulib/tests/gnulib.mk from "../../.." to "../..",
+  # and make tests conditional by changing "TESTS" to "GNULIB_TESTS",
   # then ensure that gnulib/tests/Makefile.in is up-to-date.
   m=gnulib/tests/gnulib.mk
-  sed 's,\.\./\.\./\.\.,../..,g' $m > $m-t
+  sed 's,\.\./\.\./\.\.,../..,g; s/^TESTS /GNULIB_TESTS /' $m > $m-t
   mv -f $m-t $m
   ${AUTOMAKE-automake} gnulib/tests/Makefile
 }

configure.ac

@@ -2020,6 +2020,27 @@ fi
 AC_MSG_RESULT([$withval])
 AM_CONDITIONAL([WITH_TESTS], [test "$withval" = "yes"])
 
+AC_ARG_ENABLE([expensive-tests],
+  [AC_HELP_STRING([--enable-expensive-tests],
+    [set the default for enabling expensive tests (gnulib and long timeouts) ]
+    [@<:@default=check@:>@; use VIR_TEST_EXPENSIVE to override during make])],
+  [case $enableval in
+    0|no) VIR_TEST_EXPENSIVE_DEFAULT=0 ;;
+    1|yes) VIR_TEST_EXPENSIVE_DEFAULT=1 ;;
+    check) ;;
+    *) AC_MSG_ERROR([bad value ${enableval} for enable-expensive-tests option])
+      ;;
+  esac], [enableval=check])
+if test "$enableval" = check; then
+  if test -d $srcdir/.git ; then
+    VIR_TEST_EXPENSIVE_DEFAULT=0
+  else
+    VIR_TEST_EXPENSIVE_DEFAULT=1
+  fi
+fi
+AC_SUBST([VIR_TEST_EXPENSIVE_DEFAULT])
+AM_CONDITIONAL([WITH_EXPENSIVE_TESTS], [test $VIR_TEST_EXPENSIVE_DEFAULT = 1])
+
 AC_ARG_ENABLE([test-coverage],
   AC_HELP_STRING([--enable-test-coverage], [turn on code coverage instrumentation @<:@default=no@:>@]),
 [case "${enableval}" in

docs/hacking.html.in

@@ -118,6 +118,18 @@
         variables.
         </p>
 
+        <p>
+          Some tests are skipped by default in a development environment,
+          based on the time they take in comparison to the likelihood
+          that those tests will turn up problems during incremental builds.
+          These tests default to being run when when building from a
+          tarball or with the configure option --enable-expensive-tests;
+          you can also force a one-time toggle of these tests by
+          setting VIR_TEST_EXPENSIVE to 0 or 1 at make time, as in:
+        </p>
+<pre>
+  make check VIR_TEST_EXPENSIVE=1
+</pre>
         <p>
           If you encounter any failing tests, the VIR_TEST_DEBUG
           environment variable may provide extra information to debug

gnulib/tests/Makefile.am

@@ -1,4 +1,4 @@
-## Makefile for gnulib/lib				-*-Makefile-*-
+## Makefile for gnulib/lib
 
 ## Copyright (C) 2011, 2013 Red Hat, Inc.
 ##
@@ -19,3 +19,16 @@
 include gnulib.mk
 
 INCLUDES = $(GETTEXT_CPPFLAGS)
+
+GNULIB_TESTS0 =
+GNULIB_TESTS1 = $(GNULIB_TESTS)
+if WITH_EXPENSIVE_TESTS
+## Automake requires that at least one conditional call out all tests to
+## be run, for those tests to be shipped in the tarball
+TESTS = $(GNULIB_TESTS)
+endif
+## However, we want to change the set of tests based on the make environment,
+## where the default was set at configure time.  Use GNU make constructs to
+## hide our actions from Automake, so we don't get it too confused.
+VIR_TEST_EXPENSIVE ?= $(VIR_TEST_EXPENSIVE_DEFAULT)
+$(eval TESTS=$(GNULIB_TESTS$(VIR_TEST_EXPENSIVE)))

libvirt.spec.in

@@ -1410,6 +1410,7 @@ of recent versions of Linux (and other OSes).
            --with-qemu-user=%{qemu_user} \
            --with-qemu-group=%{qemu_group} \
            %{?enable_werror} \
+           --enable-expensive-tests \
            %{init_scripts}
 make %{?_smp_mflags}
 gzip -9 ChangeLog

mingw-libvirt.spec.in

@@ -156,8 +156,8 @@ autoreconf -if
   --without-parallels \
   --without-netcf \
   --without-audit \
-  --without-dtrace
-
+  --without-dtrace \
+  --enable-expensive-tests
 
 %mingw_make %{?_smp_mflags}
 

tests/Makefile.am

@@ -307,6 +307,7 @@ lv_abs_top_builddir=`cd '$(top_builddir)'; pwd`
 path_add = $(subst :,$(PATH_SEPARATOR),\
 	$(subst !,$(lv_abs_top_builddir)/,!daemon:!tools:!tests))
 
+VIR_TEST_EXPENSIVE ?= $(VIR_TEST_EXPENSIVE_DEFAULT)
 TESTS_ENVIRONMENT =				\
   abs_top_builddir=$(lv_abs_top_builddir)	\
   abs_top_srcdir=`cd '$(top_srcdir)'; pwd`	\
@@ -318,6 +319,7 @@ TESTS_ENVIRONMENT =				\
   LIBVIRT_DRIVER_DIR="$(abs_top_builddir)/src/.libs" \
   LIBVIRT_AUTOSTART=0				\
   LC_ALL=C					\
+  VIR_TEST_EXPENSIVE=$(VIR_TEST_EXPENSIVE)	\
   $(VG)