ctest: Restore Windows Error Reporting in interactive mode

This behavior was removed when we switched to libuv in CMake 3.11.
After backporting new changes from libuv v2, we can restore the
behavior.

Fixes: #20115

Help/manual/ctest.1.rst

@@ -353,18 +353,32 @@ Run Tests
  This allows the user to widen the output to avoid clipping the test
  name which can be very annoying.
 
-.. option:: --interactive-debug-mode [0|1]
+.. option:: --interactive-debug-mode <0|1>
 
- Set the interactive mode to ``0`` or ``1``.
+ Disable (``0``) or enable (``1``) interactive debug mode.
 
  This option causes CTest to run tests in either an interactive mode
  or a non-interactive mode.  In dashboard mode (``Experimental``, ``Nightly``,
  ``Continuous``), the default is non-interactive.  In non-interactive mode,
  the environment variable :envvar:`DASHBOARD_TEST_FROM_CTEST` is set.
 
- Prior to CMake 3.11, interactive mode on Windows allowed system debug
- popup windows to appear.  Now, due to CTest's use of ``libuv`` to launch
- test processes, all system debug popup windows are always blocked.
+ Interactive Mode allows Windows Error Reporting (WER) to show debug popup
+ windows and to create core dumps.  To enable core dumps in tests,
+ use interactive mode, and follow the Windows documentation
+ on `Collecting User-Mode Dumps`_.
+
+ .. versionchanged:: 3.32
+   Windows Error Reporting (WER) is enabled in interactive mode, so
+   test processes may show debug popup windows and create core dumps.
+   This was made possible by updates to ``libuv``.
+
+ .. versionchanged:: 3.11
+   Windows Error Reporting (WER) is disabled in both interactive and
+   non-interactive modes, so test processes do not show popup windows
+   or create core dumps.  This is due to launching test processes with
+   ``libuv``.
+
+.. _`Collecting User-Mode Dumps`: https://learn.microsoft.com/en-us/windows/win32/wer/collecting-user-mode-dumps
 
 .. option:: --no-label-summary
 

Help/release/dev/ctest-crash-handling.rst

@@ -0,0 +1,7 @@
+ctest-crash-handling
+--------------------
+
+* The :option:`ctest --interactive-debug-mode` option on Windows
+  now enables Windows Error Reporting by default in test processes,
+  allowing them to creating debug popup windows and core dumps.
+  This restores behavior previously removed by CMake 3.11.

Source/CTest/cmProcess.cxx

@@ -106,6 +106,11 @@ bool cmProcess::StartProcess(uv_loop_t& loop, std::vector<size_t>* affinity)
   options.stdio_count = 3; // in, out and err
   options.exit_cb = &cmProcess::OnExitCB;
   options.stdio = stdio;
+#if UV_VERSION_MAJOR > 1 || !defined(CMAKE_USE_SYSTEM_LIBUV)
+  if (!this->Runner->GetCTest()->GetInteractiveDebugMode()) {
+    options.flags = UV_PROCESS_WINDOWS_USE_PARENT_ERROR_MODE;
+  }
+#endif
 #if !defined(CMAKE_USE_SYSTEM_LIBUV)
   std::vector<char> cpumask;
   if (affinity && !affinity->empty()) {
@@ -122,9 +127,6 @@ bool cmProcess::StartProcess(uv_loop_t& loop, std::vector<size_t>* affinity)
 #else
   static_cast<void>(affinity);
 #endif
-#if UV_VERSION_MAJOR > 1 || !defined(CMAKE_USE_SYSTEM_LIBUV)
-  options.flags = UV_PROCESS_WINDOWS_USE_PARENT_ERROR_MODE;
-#endif
 
   status =
     uv_read_start(pipe_reader, &cmProcess::OnAllocateCB, &cmProcess::OnReadCB);

Source/cmCTest.cxx

@@ -3096,6 +3096,11 @@ int cmCTest::GetSubmitIndex() const
   return this->Impl->SubmitIndex;
 }
 
+bool cmCTest::GetInteractiveDebugMode() const
+{
+  return this->Impl->InteractiveDebugMode;
+}
+
 bool cmCTest::GetLabelSummary() const
 {
   return this->Impl->LabelSummary;

Source/cmCTest.h

@@ -389,6 +389,8 @@ public:
 
   void AddSiteProperties(cmXMLWriter& xml, cmake* cm);
 
+  bool GetInteractiveDebugMode() const;
+
   bool GetLabelSummary() const;
   bool GetSubprojectSummary() const;