Travis-ci: integrate perft checking

makes verifying perft numbers for a few positions
part of travis-ci. Adds <5s testing time.

No functional change.

.travis.yml

@@ -9,7 +9,7 @@ matrix:
       addons:
         apt:
           sources: ['ubuntu-toolchain-r-test']
-          packages: ['g++-6', 'g++-6-multilib', 'g++-multilib', 'valgrind']
+          packages: ['g++-6', 'g++-6-multilib', 'g++-multilib', 'valgrind', 'expect']
       env:
         - COMPILER=g++-6
         - COMP=gcc
@@ -19,7 +19,7 @@ matrix:
       addons:
         apt:
           sources: ['ubuntu-toolchain-r-test']
-          packages: ['clang', 'g++-multilib', 'valgrind']
+          packages: ['clang', 'g++-multilib', 'valgrind', 'expect']
       env:
         - COMPILER=clang++
         - COMP=clang
@@ -49,6 +49,14 @@ script:
   - echo "Checking for same bench numbers..."
   - diff bench1 bench2 > result
   - test ! -s result
+  # verify perft numbers (positions from https://chessprogramming.wikispaces.com/Perft+Results)
+  - printf ' set timeout 10\n lassign $argv pos depth result\n spawn ./stockfish\n send "position $pos\\n perft $depth\\n"\n expect "Nodes searched  ? $result" {} timeout {exit 1} \n send "quit\\n"\n expect eof\n' > perft.exp
+  - expect perft.exp startpos 5 4865609 > /dev/null
+  - expect perft.exp "fen r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq -" 5 193690690 > /dev/null
+  - expect perft.exp "fen 8/2p5/3p4/KP5r/1R3p1k/8/4P1P1/8 w - -" 6 11030083 > /dev/null
+  - expect perft.exp "fen r3k2r/Pppp1ppp/1b3nbN/nP6/BBP1P3/q4N2/Pp1P2PP/R2Q1RK1 w kq - 0 1" 5 15833292 > /dev/null
+  - expect perft.exp "fen rnbq1k1r/pp1Pbppp/2p5/8/2B5/8/PPP1NnPP/RNBQK2R w KQ - 1 8" 5 89941194 > /dev/null
+  - expect perft.exp "fen r4rk1/1pp1qppp/p1np1n2/2b1p1B1/2B1P1b1/P1NP1N2/1PP1QPPP/R4RK1 w - - 0 10" 5 164075551 > /dev/null
   # if valgrind is available check the build is without error, reduce depth to speedup testing, but not too shallow to catch more cases.
   - if [ -x "$(command -v valgrind )" ] ; then make clean && make ARCH=x86-64 debug=yes build && valgrind --error-exitcode=42 ./stockfish bench 128 1 10 default depth 1>/dev/null ; fi
   # use g++-6 as a proxy for having sanitizers ... might need revision as they become available for more recent versions of clang/gcc than trusty provides