Fix for Boolean types (#5379) (#5466)

The packing/unpacking steps for Boolean values was failing because the
code expected numerical values. I overrode the functions for the Boolean
metatable to account for this. I also had to exclude the Boolean
metatable from the GenerateTypes helper function, as that was overriding
the Pack/Unpack functions defined in its metatable.

Added Linux bash script to run Lua tests from the command line.

Bug: google/flatbuffers#5379

Tested: Added Lua tests that were failing and are now fixed with the
code changes.

tests/LuaTest.sh

@@ -0,0 +1,22 @@
+#!/bin/bash -eu
+#
+# Copyright 2019 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+pushd "$(dirname $0)" >/dev/null
+test_dir="$(pwd)"
+
+${test_dir}/../flatc --lua -I include_test monster_test.fbs
+
+lua5.3 luatest.lua

tests/luatest.lua

@@ -9,9 +9,7 @@ local function checkReadBuffer(buf, offset, sizePrefix)
     
     if sizePrefix then               
         local size = flatbuffers.N.Int32:Unpack(buf, offset)
-        -- no longer matches python tests, but the latest 'monsterdata_test.mon'
-        -- is 448 bytes, minus 4 to arrive at the 444
-        assert(size == 444)
+        assert(size == #buf - offset - 4)
         offset = offset + flatbuffers.N.Int32.bytewidth
     end    
     
@@ -136,6 +134,10 @@ local function generateMonster(sizePrefix)
     monster.AddTestType(b, 1)
     monster.AddTest(b, mon2)
     monster.AddTest4(b, test4)
+    monster.AddTestbool(b, true)
+    monster.AddTestbool(b, false)
+    monster.AddTestbool(b, null)
+    monster.AddTestbool(b,"true")
     monster.AddTestarrayofstring(b, testArrayOfString)
     monster.AddVectorOfLongs(b, vectorOfLongs)
     monster.AddVectorOfDoubles(b, vectorOfDoubles)