Module:LibraryUtil

--[[

   Code released under the GPL v2+ as per:
   https://github.com/wikimedia/mediawiki-extensions-Scribunto/blob/7d676c3/COPYING

   @license GNU GPL v2+
   @author Brad Jorsch < bjorsch@wikimedia.org >
   @author "Mr. Stradivarius" < misterstrad@gmail.com >

]]

local LibraryUtil = {}

function LibraryUtil.checkType( name, argIdx, arg, expectType, nilOk )

   if arg == nil and nilOk then
       return
   end
   if type( arg ) ~= expectType then
       local msg = string.format( "bad argument #%d to '%s' (%s expected, got %s)",
           argIdx, name, expectType, type( arg )
       )
       error( msg, 3 )
   end

end

function LibraryUtil.checkTypeMulti( name, argIdx, arg, expectTypes )

   local argType = type( arg )
   for _, expectType in ipairs( expectTypes ) do
       if argType == expectType then
           return
       end
   end
   local n = #expectTypes
   local typeList
   if n > 1 then
       typeList = table.concat( expectTypes, ', ', 1, n - 1 ) .. ' or ' .. expectTypes[n]
   else
       typeList = expectTypes[1]
   end
   local msg = string.format( "bad argument #%d to '%s' (%s expected, got %s)",
       argIdx,
       name,
       typeList,
       type( arg )
   )
   error( msg, 3 )

end

function LibraryUtil.checkTypeForIndex( index, value, expectType )

   if type( value ) ~= expectType then
       local msg = string.format( "value for index '%s' must be %s, %s given",
           index, expectType, type( value )
       )
       error( msg, 3 )
   end

end

function LibraryUtil.checkTypeForNamedArg( name, argName, arg, expectType, nilOk )

   if arg == nil and nilOk then
       return
   end
   if type( arg ) ~= expectType then
       local msg = string.format( "bad named argument %s to '%s' (%s expected, got %s)",
           argName, name, expectType, type( arg )
       )
       error( msg, 3 )
   end

end

function LibraryUtil.makeCheckSelfFunction( libraryName, varName, selfObj, selfObjDesc )

   return function ( self, method )
       if self ~= selfObj then
           error( string.format(
               "%s: invalid %s. Did you call %s with a dot instead of a colon, i.e. " ..
               "%s.%s() instead of %s:%s()?",
               libraryName, selfObjDesc, method, varName, method, varName, method
           ), 3 )
       end
   end

end

return LibraryUtil