CTest: Fix reported duration on timeout when grindchild keeps pipes open

Since commit d1976cd1f2 (CTest: Fix timeout when grandchild keeps pipes
open, 2020-01-13, v3.17.0-rc1~169^2) we no longer hang, but the test
duration we report after the timeout is the amount of time the immediate
child ran before exiting.  Fix the logic to instead report the actual
amount of time we spent monitoring the test before the timeout.

Fixes: #20509

Source/CTest/cmProcess.cxx

@@ -249,7 +249,7 @@ void cmProcess::OnRead(ssize_t nread, const uv_buf_t* buf)
   this->PipeReader.reset();
   if (this->ProcessHandleClosed) {
     uv_timer_stop(this->Timer);
-    this->Runner.FinalizeTest();
+    this->Finish();
   }
 }
 
@@ -291,7 +291,7 @@ void cmProcess::OnTimeout()
     // Our on-exit handler already ran but did not finish the test
     // because we were still reading output.  We've just dropped
     // our read handler, so we need to finish the test now.
-    this->Runner.FinalizeTest();
+    this->Finish();
   }
 }
 
@@ -321,6 +321,16 @@ void cmProcess::OnExit(int64_t exit_status, int term_signal)
   // Record exit information.
   this->ExitValue = exit_status;
   this->Signal = term_signal;
+
+  this->ProcessHandleClosed = true;
+  if (this->ReadHandleClosed) {
+    uv_timer_stop(this->Timer);
+    this->Finish();
+  }
+}
+
+void cmProcess::Finish()
+{
   this->TotalTime = std::chrono::steady_clock::now() - this->StartTime;
   // Because of a processor clock scew the runtime may become slightly
   // negative. If someone changed the system clock while the process was
@@ -329,12 +339,7 @@ void cmProcess::OnExit(int64_t exit_status, int term_signal)
   if (this->TotalTime <= cmDuration::zero()) {
     this->TotalTime = cmDuration::zero();
   }
-
-  this->ProcessHandleClosed = true;
-  if (this->ReadHandleClosed) {
-    uv_timer_stop(this->Timer);
-    this->Runner.FinalizeTest();
-  }
+  this->Runner.FinalizeTest();
 }
 
 cmProcess::State cmProcess::GetProcessStatus()

Source/CTest/cmProcess.h

@@ -101,6 +101,7 @@ private:
   void OnAllocate(size_t suggested_size, uv_buf_t* buf);
 
   void StartTimer();
+  void Finish();
 
   class Buffer : public std::vector<char>
   {

Tests/RunCMake/CTestTimeout/Basic-stdout.txt

@@ -1,6 +1,6 @@
 Test project [^
 ]*/Tests/RunCMake/CTestTimeout/Basic-build
     Start 1: TestTimeout
-1/1 Test #1: TestTimeout ......................\*\*\*Timeout +[0-9.]+ sec
+1/1 Test #1: TestTimeout ......................\*\*\*Timeout +[1-9][0-9.]* sec
 +
 0% tests passed, 1 tests failed out of 1

Tests/RunCMake/CTestTimeout/Fork-stdout.txt

@@ -1,6 +1,6 @@
 Test project [^
 ]*/Tests/RunCMake/CTestTimeout/Fork-build
     Start 1: TestTimeout
-1/1 Test #1: TestTimeout ......................\*\*\*Timeout +[0-9.]+ sec
+1/1 Test #1: TestTimeout ......................\*\*\*Timeout +[1-9][0-9.]* sec
 +
 0% tests passed, 1 tests failed out of 1