fix aha.svc.mirror bugs (SYN-11299)

changes/97be8d1fc0995d182d1d578fa598ca22.yaml

@@ -0,0 +1,8 @@
+---
+desc: Fixed an issue where the ``synapse.tests.utils.TstOutPut.expect()`` test helper
+  ignored the caller's string when called with ``whitespace=False``, causing those
+  assertions to always pass.
+desc:literal: false
+prs: []
+type: bug
+...

changes/a0042c7e6f67dc0c4915db5c390acf1d.yaml

@@ -0,0 +1,9 @@
+---
+desc: Fixed an issue where the ``aha.svc.mirror`` Storm command and the ``synapse.tools.aha.mirror``
+  tool reported a mirror group as being in sync when no member of the group responded,
+  and where a service which responded under its leader alias name was reported with
+  an unknown status.
+desc:literal: false
+prs: []
+type: bug
+...

changes/ccaf3521f3a56eb95f109570850e0c64.yaml

@@ -0,0 +1,11 @@
+---
+desc: Updated the ``aha.svc.mirror`` Storm command and the ``synapse.tools.aha.mirror``
+  tool to identify mirror group members by their shared service iden. Mirror groups are
+  now displayed even when no service has claimed the group leader name. Added a ``follows``
+  column which displays the service that each member mirrors from, and a ``Group Leader``
+  line which displays the service currently reporting itself as the leader. Both report
+  ``No mirror groups found.`` when there are no mirror groups to display.
+desc:literal: false
+prs: []
+type: feat
+...

docs/synapse/userguides/storm_ref_cmd.rstorm

@@ -175,6 +175,7 @@ service pools.
 - `aha.pool.svc.add`_
 - `aha.pool.svc.del`_
 - `aha.svc.list`_
+- `aha.svc.mirror`_
 - `aha.svc.stat`_
 
 Help for individual ``aha.*`` commands can be displayed using:
@@ -253,6 +254,18 @@ The ``aha.svc.list`` command lists AHA services.
 .. storm-cli:: aha.svc.list --help
 
 
+.. _storm-aha-svc-mirror:
+
+aha.svc.mirror
+++++++++++++++
+
+The ``aha.svc.mirror`` command displays AHA mirror groups and the status of their members.
+
+**Syntax:**
+
+.. storm-cli:: aha.svc.mirror --help
+
+
 .. _storm-aha-svc-stat:
 
 aha.svc.stat