test: fix debug test crashes caused by sea tests

test/sea/testcfg.py

@@ -5,7 +5,15 @@
 def GetConfiguration(context, root):
   # We don't use arch-specific out folder in Node.js; use none/none to auto
   # detect release mode from GetVm and get the path to the executable.
-  vm = context.GetVm('none', 'none')
+  try:
+    vm = context.GetVm('none', 'none')
+  except ValueError:
+    # In debug only builds, we are getting an exception because none/none
+    # results in taking the release flavor that is missing in that case. Try to
+    # recover by using the first mode passed explicitly to the test.py.
+    preferred_mode = getattr(context, 'default_mode', 'none') or 'none'
+    vm = context.GetVm('none', preferred_mode)
+
   if not os.path.isfile(vm):
     return testpy.SimpleTestConfiguration(context, root, 'sea')
 

tools/test.py

@@ -1697,6 +1697,14 @@ def Main():
                     options.store_unexpected_output,
                     options.repeat,
                     options.abort_on_timeout)
+  # Remember the primary mode requested on the CLI so suites can reuse it when
+  # they need to probe for a binary outside of the normal test runner flow.
+  for requested_mode in options.mode:
+    if requested_mode:
+      context.default_mode = requested_mode
+      break
+  else:
+    context.default_mode = 'none'
 
   if options.error_reporter:
     context.use_error_reporter = True