[tests] Fix threading issue with parallel testing with non-threadsafe rspec mocks

Author: chadlwilson

src/spec/ruby/rack/application_spec.rb

@@ -798,27 +798,35 @@ def createRackServletWrapper(runtime, rackup, filename)
     expect(java.lang.System.currentTimeMillis - start).to be_within(20).of(timeout_millis)
   end
 
-  it "initializes initial runtimes in paralel (with wait set to false)" do
+  it "initializes initial runtimes in parallel (with wait set to false)" do
+    @factory = double("factory (non-tracking)").as_null_object
+    @pooling_factory = org.jruby.rack.PoolingRackApplicationFactory.new @factory
+    @pooling_factory.context = @rack_context
+
+    app_init_secs = 0.05
     allow(@factory).to receive(:init)
     allow(@factory).to receive(:newApplication) do
-      app = double "app"
-      allow(app).to receive(:init) do
-        sleep(0.15)
-      end
+      app = double("app").as_null_object
+      allow(app).to receive(:init) { sleep(app_init_secs) }
       app
     end
+
+    init_threads = 4
+    init_runtimes = 6
     allow(@rack_config).to receive(:getBooleanProperty).with("jruby.runtime.init.wait").and_return false
-    allow(@rack_config).to receive(:getInitialRuntimes).and_return 6
+    allow(@rack_config).to receive(:getRuntimeInitThreads).and_return init_threads
+    allow(@rack_config).to receive(:getInitialRuntimes).and_return init_runtimes
     allow(@rack_config).to receive(:getMaximumRuntimes).and_return 8
 
+    expected_initial_init_time = 1.1 * (init_runtimes.to_f / init_threads.to_f).ceil * app_init_secs # 10% margin
     @pooling_factory.init(@rack_context)
-    sleep(0.10)
-    expect(@pooling_factory.getApplicationPool.size).to be < 6
-    sleep(0.9)
-    expect(@pooling_factory.getApplicationPool.size).to be >= 6
+    sleep(app_init_secs) # wait for at some (but not possibly all) to finish
+    expect(@pooling_factory.getApplicationPool.size).to be < init_runtimes
+    sleep(expected_initial_init_time - app_init_secs) # remaining time
+    expect(@pooling_factory.getApplicationPool.size).to be >= init_runtimes
 
     expect(@pooling_factory.getManagedApplications).to_not be_empty
-    expect(@pooling_factory.getManagedApplications.size).to eql 6
+    expect(@pooling_factory.getManagedApplications.size).to eql init_runtimes
   end
 
   it "throws from init when application initialization in thread failed" do