Report SMTP-27 delivery matrix on timeout

contrib/testing/smtp-dane-mta-sts-check.py

@@ -568,16 +568,36 @@ def validate_initial(
                "initial")
         for name in failure
     }
-    wait_until(
-        lambda: (
-            all(matching_messages(
-                captures[name],
-                next(route for route in ROUTES if route.name == name),
-                "initial") for name in success)
-            and queued_tokens(queued) == queued
-        ),
-        "DANE and MTA-STS initial outcomes",
-    )
+    try:
+        wait_until(
+            lambda: (
+                all(matching_messages(
+                    captures[name],
+                    next(route for route in ROUTES if route.name == name),
+                    "initial") for name in success)
+                and queued_tokens(queued) == queued
+            ),
+            "DANE and MTA-STS initial outcomes",
+        )
+    except SMTP27Error as error:
+        details = []
+        for route in ROUTES:
+            connections, starttls, messages = captures[route.name].snapshot()
+            matching = len(matching_messages(
+                captures[route.name], route, "initial"))
+            details.append(
+                f"{route.name}: connections={connections}, "
+                f"starttls={starttls}, messages={len(messages)}, "
+                f"matching={matching}")
+        found = queued_tokens(queued)
+        details.append(
+            "queued expected="
+            + ",".join(sorted(queued))
+            + " found="
+            + ",".join(sorted(found)))
+        raise SMTP27Error(
+            str(error) + "\n--- delivery matrix ---\n"
+            + "\n".join(details)) from error
     for name in success:
         route = next(route for route in ROUTES if route.name == name)
         messages = matching_messages(captures[name], route, "initial")