Tests: add luacheck for linting tests

Source: https://github.com/mpeterv/luacheck
Docs:   http://luacheck.readthedocs.org/en/0.12.0/index.html

Run via "make testlint".

CMakeLists.txt

@@ -366,6 +366,8 @@ if(NOT BUSTED_OUTPUT_TYPE)
   set(BUSTED_OUTPUT_TYPE "utfTerminal")
 endif()
 
+find_program(LUACHECK_PRG luacheck)
+
 include(InstallHelpers)
 
 file(GLOB MANPAGES
@@ -456,3 +458,11 @@ if(BUSTED_PRG)
       -P ${PROJECT_SOURCE_DIR}/cmake/RunTests.cmake
     DEPENDS ${BENCHMARK_PREREQS})
 endif()
+
+if(LUACHECK_PRG)
+  add_custom_target(testlint
+    COMMAND ${CMAKE_COMMAND}
+      -DLUACHECK_PRG=${LUACHECK_PRG}
+      -DTEST_DIR=${CMAKE_CURRENT_SOURCE_DIR}/test
+      -P ${PROJECT_SOURCE_DIR}/cmake/RunTestsLint.cmake)
+endif()

Makefile

@@ -86,6 +86,9 @@ oldtest: | nvim
 functionaltest: | nvim
 	+$(BUILD_CMD) -C build functionaltest
 
+testlint: | nvim
+	$(BUILD_CMD) -C build testlint
+
 test: functionaltest
 
 unittest: | nvim
@@ -110,4 +113,4 @@ lint:
 		-DLINT_SUPPRESS_URL="$(DOC_DOWNLOAD_URL_BASE)$(CLINT_ERRORS_FILE_PATH)" \
 		-P cmake/RunLint.cmake
 
-.PHONY: test functionaltest unittest lint clean distclean nvim libnvim cmake deps install
+.PHONY: test testlint functionaltest unittest lint clean distclean nvim libnvim cmake deps install

cmake/RunTestsLint.cmake

@@ -0,0 +1,11 @@
+execute_process(
+  COMMAND ${LUACHECK_PRG} -q ${TEST_DIR}
+  WORKING_DIRECTORY ${TEST_DIR}
+  ERROR_VARIABLE err
+  RESULT_VARIABLE res
+  ${EXTRA_ARGS})
+
+if(NOT res EQUAL 0)
+  message(STATUS "Output to stderr:\n${err}")
+  message(FATAL_ERROR "Linting tests failed with error: ${res}.")
+endif()

test/.luacheckrc

@@ -0,0 +1,4 @@
+-- vim: ft=lua
+
+std = '+luajit +busted'
+cache = true

third-party/cmake/BuildLuarocks.cmake

@@ -121,12 +121,19 @@ if(USE_BUNDLED_BUSTED)
   add_custom_target(busted
     DEPENDS ${HOSTDEPS_BIN_DIR}/busted)
 
+  add_custom_command(OUTPUT ${HOSTDEPS_BIN_DIR}/luacheck
+    COMMAND ${LUAROCKS_BINARY}
+    ARGS build https://raw.githubusercontent.com/mpeterv/luacheck/0.12.0/luacheck-scm-1.rockspec ${LUAROCKS_BUILDARGS}
+    DEPENDS busted)
+  add_custom_target(luacheck
+    DEPENDS ${HOSTDEPS_BIN_DIR}/luacheck)
+
   add_custom_command(OUTPUT ${HOSTDEPS_LIB_DIR}/luarocks/rocks/nvim-client
     COMMAND ${LUAROCKS_BINARY}
     ARGS build https://raw.githubusercontent.com/neovim/lua-client/0.0.1-14/nvim-client-0.0.1-14.rockspec ${LUAROCKS_BUILDARGS} LIBUV_DIR=${HOSTDEPS_INSTALL_DIR}
-    DEPENDS busted libuv)
+    DEPENDS luacheck libuv)
   add_custom_target(nvim-client
     DEPENDS ${HOSTDEPS_LIB_DIR}/luarocks/rocks/nvim-client)
 
-  list(APPEND THIRD_PARTY_DEPS busted nvim-client)
+  list(APPEND THIRD_PARTY_DEPS busted luacheck nvim-client)
 endif()