recheck thread exit code before reporting doa minion

pitest-entry/src/main/java/org/pitest/coverage/execute/CoverageProcess.java

@@ -37,6 +37,12 @@ public ExitCode waitToDie() {
       while (!maybeExit.isPresent() && this.process.isAlive()) {
         maybeExit = this.crt.waitToFinish(10);
       }
+
+      // Either the monitored process died, or the thread ended.
+      // Check the thread one last time to try and avoid reporting
+      // an error code if it was the process that went down first
+      maybeExit = this.crt.waitToFinish(10);
+
       return maybeExit.orElse(ExitCode.MINION_DIED);
     } finally {
       this.process.destroy();

pitest-entry/src/main/java/org/pitest/mutationtest/execute/MutationTestProcess.java

@@ -51,7 +51,8 @@ public ExitCode waitToDie() {
     try {
       // Wait a moment to give the monitoring thread time to finish naturally. This
       // happens when the monitored process sends a "DONE" signal over the socket,
-      // the process itself should exit shortly after sending the signal
+      // the process itself should exit shortly after sending the signal.
+      // Most likely the process will still be running
       Optional<ExitCode> maybeExit = this.thread.waitToFinish(5);
 
       // While the monitored process reports being alive, keep polling
@@ -60,6 +61,11 @@ public ExitCode waitToDie() {
         maybeExit = this.thread.waitToFinish(10);
       }
 
+      // Either the monitored process died, or the thread ended.
+      // Check the thread one last time to try and avoid reporting
+      // an error code if it was the process that went down first
+      maybeExit = this.thread.waitToFinish(10);
+
       // If the monitored thread is still live, but the process is dead
       // then either the process never properly started or it died
       // before reporting its exit