Ruby threads not ending after running test suite

[johnschoeman]

Metadata

• Ruby version: 2.5.1
• @prettier/plugin-ruby version: 0.12.3

Input

yarn run test

Current output

Expected output

For the specs to tear down any and all spawned threads.

---

When running the test suite with: yarn run test many ruby threads will start to run the parser, ./test/js/parser.rb The specs will complete but the threads will not stop executing. This compounds with multiple runs of the test suite.

Currently on my machine it looks like there are 32 threads which are being started but not closed. I've just been manually killing the processes.

[johnschoeman]

@tuskerette and I did some digging into the test setup and identified the source of the issue:

setupTests.js will spawn a process for the test parser:

const parser = spawn("ruby", ["./test/js/parser.rb"]);

the ruby file ./test/js/parser.rb has two nested loops:

loop do
  lines, line = [], nil
  lines << line while (line = gets) != "---\n"

  parser = RipperJS.new(lines.join)

  STDOUT.puts JSON.fast_generate(parser.parse)
  STDOUT.flush
end

The inner while loop will break when the stdin equals "---\n", however there are times when gets will never equal "---\n" and hence the process will never terminate.

It's not clear to us exactly why this is, we would expect that 'rl.question(${before}\n---\n, ... ' in the setupTests.js file would ensure that all the read lines end with ---\n.

the code below technically fixes the bug, but we should identity a better fix:

loop do
  lines, line = [], nil

  i = 0
  while (line = gets) != "---\n" do
    lines << line
    i += 1
    if i > 100
      break
    end
  end

  parser = RipperJS.new(lines.join)

  STDOUT.puts JSON.fast_generate(parser.parse)
  STDOUT.flush
end

we have a wip commit here: #324

[kddnewton]

Going to close this issue in favor of moving the discussion to #381