Add& use Luacheck support

This commit adds a new "luacheck" target to the Makefiles. This target is
automatically included in "make check" when luacheck is found in $PATH.
Additionally, this includes luacheck in Travis so that the build fails when
luacheck complains about something.

Signed-off-by: Uli Schlachter <psychon@znc.in>

.luacheckrc

@@ -0,0 +1,36 @@
+-- Only allow symbols available in all Lua versions
+std = "min"
+
+-- Get rid of "unused argument self"-warnings
+self = false
+
+-- The unit tests can use busted
+files["spec"].std = "+busted"
+
+-- The default config may set global variables
+files["awesomerc.lua"].allow_defined_top = true
+
+-- Global objects defined by the C code
+read_globals = {
+    "awesome",
+    "button",
+    "client",
+    "dbus",
+    "drawable",
+    "drawin",
+    "key",
+    "keygrabber",
+    "mouse",
+    "mousegrabber",
+    "root",
+    "screen",
+    "selection",
+    "tag",
+    "window",
+}
+-- May not be read-only due to client.focus
+globals = {
+    "client"
+}
+
+-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80

.travis.yml

@@ -66,8 +66,10 @@ install:
   - sudo apt-get install -y gir1.2-pango-1.0 libgirepository1.0-dev
   - travis_retry sudo luarocks install lgi $LGIVER
 
-  # Install busted for "make check".
+  # Install busted for "make check-unit".
   - travis_retry sudo luarocks install busted
+  # Install luacheck for "make luacheck".
+  - travis_retry sudo luarocks install luacheck
 
   # Install ldoc for building docs.
   - travis_retry sudo luarocks install ldoc

CMakeLists.txt

@@ -352,14 +352,24 @@ endif()
 # }}}
 
 # {{{ Tests
+set(CHECK_TARGETS check-integration)
+add_custom_target(check-integration
+    "${CMAKE_SOURCE_DIR}/tests/run.sh"
+    WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+    COMMENT "Running integration tests"
+    VERBATIM)
 find_program(BUSTED_EXECUTABLE busted)
 if(BUSTED_EXECUTABLE)
+    # Keep the arguments in sync with the version below!
     add_custom_target(check-unit ALL
         ${BUSTED_EXECUTABLE} "--helper=${CMAKE_SOURCE_DIR}/spec/preload.lua"
         "--lpath=${CMAKE_BINARY_DIR}/lib/?.lua;${CMAKE_BINARY_DIR}/lib/?/init.lua;spec/?.lua"
         WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
         COMMENT "Running unit tests"
         VERBATIM)
+    list(APPEND CHECK_TARGETS check-unit)
+
+    # Same as above, but with --coverage argument
     add_custom_target(check-coverage
         "BUILD_DIRECTORY=${CMAKE_BINARY_DIR}/"
         ${BUSTED_EXECUTABLE} "--helper=${CMAKE_SOURCE_DIR}/spec/preload.lua"
@@ -369,16 +379,16 @@ if(BUSTED_EXECUTABLE)
         COMMENT "Running unit tests under LuaCov"
         VERBATIM)
 endif()
-add_custom_target(check-integration
-    "${CMAKE_SOURCE_DIR}/tests/run.sh"
+find_program(LUACHECK_EXECUTABLE luacheck)
+if(LUACHECK_EXECUTABLE)
+    add_custom_target(luacheck
+        ${LUACHECK_EXECUTABLE} lib spec tests themes awesomerc.lua
         WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
-    COMMENT "Running integration tests"
+        COMMENT "Running Luacheck"
         VERBATIM)
-if(BUSTED_EXECUTABLE)
-    add_custom_target(check DEPENDS check-integration check-unit)
-else()
-    add_custom_target(check DEPENDS check-integration)
+    list(APPEND CHECK_TARGETS luacheck)
 endif()
+add_custom_target(check DEPENDS ${CHECK_TARGETS})
 # }}}
 
 # vim: filetype=cmake:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80:foldmethod=marker