Bug #15644
Updated by kke (Kimmo Lehto) over 5 years ago
ThreadsWait spawns a new thread for waiting on a thread:
```
# thwait.rb:87
def join_nowait(*threads)
threads.flatten!
@threads.concat threads
for th in threads
Thread.start(th) do |t|
begin
t.join
ensure
@wait_queue.push t
end
end
end
end
```
As `thread.join` raises the exception from the thread, it will trigger a thread exception report.
If the thread was using `report_on_exception = false`, the wait thread will report the exception anyway.
If the thread was using `report_on_exception = true`, both threads will report the exception.
I think this could be fixed by always setting `report_on_exception = false` for the wait thread.
# Example 1
```
require 'thwait'
thread = Thread.new do
Thread.current.report_on_exception = false
sleep 1
raise "Foo"
end
ThreadsWait.all_waits(thread) do |terminated_thread|
puts "Thread #{terminated_thread} terminated"
end
```
## Expected result
No exception reports
## Actual result
The wait thread will report the exception:
```
#<Thread:0x00007fa57d092d68@/Users/user/.rbenv/versions/2.6.1/lib/ruby/2.6.0/thwait.rb:91 run> terminated with exception (report_on_exception is true):
```
# Example 2
```
require 'thwait'
thread = Thread.new do
sleep 1
raise "Foo"
end
ThreadsWait.all_waits(thread) do |terminated_thread|
puts "Thread #{terminated_thread} terminated"
end
```
## Expected result
One exception report
## Actual result
Two exception reports:
``` reports
#<Thread:0x00007f9f83053320@test.rb:3 run> terminated with exception (report_on_exception is true):
#<Thread:0x00007f9f830530a0@/Users/user/.rbenv/versions/2.6.1/lib/ruby/2.6.0/thwait.rb:91 run> terminated with exception (report_on_exception is true):
Traceback (most recent call last):
```