Log threads when the OS signal is received to simplify debugging, especially when a CI node hangs.

CHANGELOG.md

@@ -2,6 +2,14 @@
 
 ### UNRELEASED
 
+### 7.7.0
+
+* Log threads when the OS signal is received to simplify debugging, especially when a CI node hangs.
+
+    https://github.com/KnapsackPro/knapsack_pro-ruby/pull/266
+
+https://github.com/KnapsackPro/knapsack_pro-ruby/compare/v7.6.2...v7.7.0
+
 ### 7.6.2
 
 * Fix an error for the `KnapsackPro::Formatters::TimeTracker` formatter in RSpec when using Knapsack Pro Regular Mode and the `.rspec` file is not present.

lib/knapsack_pro/runners/queue/base_runner.rb

@@ -59,9 +59,37 @@ def trap_signals
             Signal.trap(signal) {
               puts "#{signal} signal has been received. Terminating Knapsack Pro..."
               @@terminate_process = true
+              log_threads
             }
           end
         end
+
+        def log_threads
+          threads = Thread.list
+
+          puts
+          puts '=' * 80
+          puts "Start logging #{threads.count} detected threads."
+          puts 'Use the following backtrace(s) to find the line of code that got stuck if the CI node hung and terminated your tests.'
+
+          threads.each do |thread|
+            puts
+            if thread == Thread.main
+              puts "Main thread backtrace:"
+            else
+              puts "Non-main thread inspect: #{thread.inspect}"
+              puts "Non-main thread backtrace:"
+            end
+            puts thread.backtrace.join("\n")
+            puts
+          end
+
+          puts
+          puts 'End logging threads.'
+          puts '=' * 80
+
+          $stdout.flush
+        end
       end
     end
   end

spec/integration/runners/queue/rspec_runner_spec.rb

@@ -1318,6 +1318,10 @@ def when_first_matching_example_defined(type:)
         describe 'A_describe' do
           it 'A1 test example' do
             expect(1).to eq 1
+
+            Thread.new do
+              sleep 10
+            end
           end
         end
       SPEC
@@ -1406,6 +1410,14 @@ def when_first_matching_example_defined(type:)
         OUTPUT
       )
 
+
+      expect(actual.stdout).to include('Use the following backtrace(s) to find the line of code that got stuck if the CI node hung and terminated your tests.')
+      expect(actual.stdout).to include('Main thread backtrace:')
+      expect(actual.stdout).to include("spec_integration/b_spec.rb:7:in `kill'")
+      expect(actual.stdout).to include('Non-main thread backtrace:')
+      expect(actual.stdout).to include("spec_integration/a_spec.rb:6:in `sleep'")
+
+
       expect(actual.exit_code).to eq 1
     end
   end