Initial googlemock/googletest integration into the build/FreeBSD test suite

This initial integration takes googlemock/googletest release 1.8.1, integrates
the library, tests, and sample unit tests into the build.

googlemock/googletest's inclusion is optionally available via `MK_GOOGLETEST`.
`MK_GOOGLETEST` is dependent on `MK_TESTS` and is enabled by default when
built with a C++11 capable toolchain.

Google tests can be specified via the `GTESTS` variable, which, in comparison
with the other test drivers, is more simplified/streamlined, as Googletest only
supports C++ tests; not raw C or shell tests (C tests can be written in C++
using the standard embedding methods).

No dependent libraries are assumed for the tests. One must specify `gmock`,
`gmock_main`, `gtest`, or `gtest_main`, via `LIBADD` for the program.

More information about googlemock and googletest can be found on the
Googletest [project page](https://github.com/google/googletest), and the
[GoogleMock](https://github.com/google/googletest/blob/v1.8.x/googlemock/docs/Documentation.md)
and
[GoogleTest](https://github.com/google/googletest/tree/v1.8.x/googletest/docs)
docs.

These tests are originally integrated into the build as plain driver tests, but
will be natively integrated into Kyua in a later version.

Known issues/Errata:
* [WhenDynamicCastToTest.AmbiguousCast fails on FreeBSD](https://github.com/google/googletest/issues/2172)

Reviewed by:	asomers
Approved by:	emaste (mentor)
MFC after:	2 months
Differential Revision: https://reviews.freebsd.org/D19551

2 files changed, 65 insertions, 0 deletions

diff --git a/share/examples/tests/tests/Makefile b/share/examples/tests/tests/Makefile
index 35106d686776..e5bbd7813352 100644
--- a/share/examples/tests/tests/Makefile
+++ b/share/examples/tests/tests/Makefile
@@ -1,5 +1,7 @@
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 # Directory into which the Kyuafile provided by this directory will be
 # installed.
 #
@@ -21,6 +23,10 @@ TESTS_SUBDIRS+=	atf
 TESTS_SUBDIRS+=	plain
 TESTS_SUBDIRS+=	tap
 
+.if ${MK_GOOGLETEST} != no
+TESTS_SUBDIRS+= googletest
+.endif
+
 # We leave KYUAFILE unset so that bsd.test.mk auto-generates a Kyuafile
 # for us based on the contents of the TESTS_SUBDIRS line above.  The
 # generated file will tell the tests run-time engine to recurse into the
diff --git a/share/examples/tests/tests/googletest/Makefile b/share/examples/tests/tests/googletest/Makefile
new file mode 100644
index 000000000000..db1cbd322d4d
--- /dev/null
+++ b/share/examples/tests/tests/googletest/Makefile
@@ -0,0 +1,59 @@
+# $FreeBSD$
+#
+# This Makefile differs from the other examples, in the sense that its purpose
+# is to install the upstream provided googletest sample unit tests.
+
+# The release package to use for the tests contained within the directory
+#
+# This applies to components which rely on ^/projects/release-pkg support
+# (see UPDATING XXXXXXXXX / svn revision r298107).
+PACKAGE=	tests
+
+# Directory into which the Kyuafile provided by this directory will be
+# installed.
+#
+# This is always a subdirectory of ${TESTSBASE}/.  The remainder of the
+# path has to match the relative path within the source tree in which
+# these files are found modulo the tests/ component at the end.
+#
+# For example: if this Makefile were in src/bin/cp/tests/, its TESTSDIR
+# would point at ${TESTSBASE}/bin/cp/.
+TESTSDIR=	${TESTSBASE}/share/examples/tests/googletest
+
+.PATH: ${SRCTOP}/contrib/googletest/googletest/samples
+
+GTEST_MAIN_REQ_TESTS+=	sample1_unittest
+GTEST_MAIN_REQ_TESTS+=	sample2_unittest
+GTEST_MAIN_REQ_TESTS+=	sample3_unittest
+GTEST_MAIN_REQ_TESTS+=	sample4_unittest
+GTEST_MAIN_REQ_TESTS+=	sample5_unittest
+GTEST_MAIN_REQ_TESTS+=	sample6_unittest
+GTEST_MAIN_REQ_TESTS+=	sample7_unittest
+GTEST_MAIN_REQ_TESTS+=	sample8_unittest
+
+# sample9_unittest's `CustomOutputTest.Fails` fails intentionally to illustrate
+# how output format can be adjusted with command-line parameters.
+#GTEST_REQ_TESTS+=	sample9_unittest
+GTEST_REQ_TESTS+=	sample10_unittest
+
+# List of test programs to build.  Note that we can build more than one
+# test from a single directory, and this is expected.
+GTESTS+=		${GTEST_MAIN_REQ_TESTS} ${GTEST_REQ_TESTS}
+
+# 
+.for t in ${GTESTS}
+.if ${GTEST_MAIN_REQ_TESTS:M$t}
+LIBADD.$t+=	gtest_main
+.else
+LIBADD.$t+=	gtest
+.endif
+SRCS.$t+=	$t.cc
+.endfor
+
+# Additional sources for sample testcase 1, 2, 4, and 5.
+SRCS.sample1_unittest+=	sample1.cc
+SRCS.sample2_unittest+=	sample2.cc
+SRCS.sample4_unittest+=	sample4.cc
+SRCS.sample5_unittest+=	sample1.cc
+
+.include <bsd.test.mk>