[RFC][PATCH 5/5] [PR gdb/33469] testsuite: framefilters-mi: async records from unwinder

["Dennis Lambe Jr." <malsyned@malsyned.net>]

Add a testsuite case to detect regressions of PR gdb/33469.
---
 gdb/testsuite/gdb.python/py-framefilter-mi.exp |  6 ++++++
 gdb/testsuite/gdb.python/py-framefilter.py     | 15 +++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/gdb/testsuite/gdb.python/py-framefilter-mi.exp b/gdb/testsuite/gdb.python/py-framefilter-mi.exp
index 03e5f90580c..df4b246f37a 100644
--- a/gdb/testsuite/gdb.python/py-framefilter-mi.exp
+++ b/gdb/testsuite/gdb.python/py-framefilter-mi.exp
@@ -71,6 +71,12 @@ mi_gdb_test "-stack-list-frames 22 24" \
     "\\^done,stack=\\\[frame={level=\"22\",addr=\"$hex\",func=\"1cnuf\".*,arch=\"$any\",children=\\\[frame={level=\"23\",addr=\"$hex\",func=\"func2\".*,arch=\"$any\"}\\\]},frame={level=\"24\",addr=\"$hex\",func=\"3cnuf\".*,arch=\"$any\"}\\\]" \
     "filtered stack list 22 24"
 
+mi_gdb_test "enable unwinder global InterruptingUnwinder" ".*1 unwinder enabled.*\\^done." "enable InterruptingUnwinder"
+mi_gdb_test "-stack-list-frames" \
+    "(=cmd-param-changed,param=\"$any\",value=\"$any\"\r?\n)+\\^done,stack=\\\[frame={level=.*" \
+    "list stack frames when unwinder emits async records"
+mi_gdb_test "disable unwinder global InterruptingUnwinder" ".*1 unwinder disabled.*\\^done." "disable InterruptingUnwinder"
+
 #stack list arguments
 
 
diff --git a/gdb/testsuite/gdb.python/py-framefilter.py b/gdb/testsuite/gdb.python/py-framefilter.py
index 5c3790d33f2..5ed95681687 100644
--- a/gdb/testsuite/gdb.python/py-framefilter.py
+++ b/gdb/testsuite/gdb.python/py-framefilter.py
@@ -20,6 +20,7 @@ import itertools
 # frame-filters.
 import gdb
 from gdb.FrameDecorator import FrameDecorator
+from gdb.unwinder import Unwinder, register_unwinder
 
 
 class Reverse_Function(FrameDecorator):
@@ -167,6 +168,20 @@ class ErrorFilter:
             return map(ErrorInName, frame_iter)
 
 
+# An unwinder that causes some async record MI traffic
+class InterruptingUnwinder(Unwinder):
+    def __init__(self):
+        super().__init__("InterruptingUnwinder")
+        self.enabled = False
+
+    def __call__(self, pending_frame):
+        language = gdb.parameter("language")
+        gdb.set_parameter("language", "c++")
+        gdb.set_parameter("language", language)
+        return None
+
+
 FrameFilter()
 FrameElider()
 ErrorFilter()
+register_unwinder(None, InterruptingUnwinder())
-- 
2.51.0