mw.smw.ask returns always false on printouts for category membership

[oetterer]

Setup and configuration

• SMW version: 2.5.5
• SSC version: master
• MW version: 1.27
• DB (MySQL etc.): mysql

Issue

for a page PAGE in category member the query

local q = '[[PAGE]]|?Category|?Category:Member|?Category:INVALID'
mw.logObject(mw.smw.ask(q))

returns

table#1 {
 table#2 {
  "[[:PAGE]]",
  ["Category"] = "[[:Category:Member|Member]]",
  ["Member"] = false,
  ["INVALID"] = false,
 },
}

[oetterer]

i have an integration test to show the problem and a fix ready. just waiting for pr #41 to be merged.