fix: keep pySim's command-set bookkeeping in sync in the ES10 selections

After a profile switch the shell was unusable: every file select failed
with 'Attribute already exists: do_decode_hex (ShellCommands)' and even
equipping did not help - only a server restart recovered it.

pySim's equip() unregisters only the command sets of the file that is
selected at that moment, then re-registers everything while selecting
MF/EF.ICCID and MF with the app as cmd_app.  esim._select_isdr() selected
the ISD-R ADF without cmd_app, so MF's sets (ShellCommands, ...) stayed
registered while the selection moved to the ADF; the equip after the
profile switch then died re-registering them (cmd2 raises
CommandSetRegistrationError), leaving the app broken.

- _select_isdr() passes the shell app as cmd_app, so the old file's sets
  are unregistered and the ADF's (none) registered.
- _restore() passes it to soft_reset() too, so the MF re-selection updates
  the bookkeeping on both the success and the failure path.
- _esim_reinit() probes select('MF', app) after the equip and reports
  reinitialized: false on a registration error (a card-level select
  failure, e.g. no active profile, is tolerated).
- tests assert the cmd_app plumbing on the ISD-R select and the restore
  (profiles, chip and both switch paths).

pysim_simple_server/esim.py

@@ -54,14 +54,20 @@ def is_euicc(app):
 
 
 def _select_isdr(app):
-    """Select ISD-R on logical channel 0; returns the lchan's scc."""
+    """Select ISD-R on logical channel 0; returns the lchan's scc.
+
+    The shell app is passed as cmd_app so pySim keeps its command-set
+    bookkeeping in sync with the selection: ``equip()`` only unregisters the
+    sets of the file selected at that moment, so a selection made without
+    cmd_app leaves the old file's sets registered and the next equip dies
+    re-registering them (cmd2: 'Attribute already exists')."""
     rs = getattr(app, 'rs', None)
     apps = getattr(getattr(rs, 'mf', None), 'applications', None) or {}
     isd_r = apps.get(AID_ISD_R.lower())
     if isd_r is None:
         raise EsimError('not_an_euicc')
     lchan = rs.lchan[0]
-    lchan.select_file(isd_r)
+    lchan.select_file(isd_r, app)
     return lchan.scc
 
 
@@ -70,9 +76,10 @@ def _restore(app):
 
     Best effort: a card whose active profile is disabled has no filesystem to
     select, so the restore can legitimately fail - the selection metadata is
-    then guarded by the status endpoint instead of crashing it."""
+    then guarded by the status endpoint instead of crashing it.  The shell app
+    is passed as cmd_app so the command-set bookkeeping follows the selection."""
     try:
-        app.rs.soft_reset()
+        app.rs.soft_reset(app)
     except Exception as e:
         sys.stderr.write('ESIM: selection restore failed: %s\n' % e)
 

pysim_simple_server/server.py

@@ -19,6 +19,7 @@ from pysim_simple_server import netstate
 from pysim_simple_server import scp81
 from pysim_simple_server import esim
 from smartcard.CardMonitoring import CardMonitor, CardObserver
+from cmd2.exceptions import CommandSetRegistrationError
 
 import gsm0338  # registers 'gsm03.38' codec
 from construct import GreedyBytes
@@ -2594,6 +2595,19 @@ def _esim_reinit(server):
             sys.stderr.write('ESIM: card gone during re-initialization\n')
             return False
         _apply_equipped_card(server)
+        # The equip must leave the shell's command-set registration consistent
+        # (pySim unregisters only the file selected at equip time).  A broken
+        # registration only shows up on the next select made with the app, so
+        # probe it here: a card-level select failure (no active profile) is
+        # acceptable, a registration error is not.
+        try:
+            server.app.rs.lchan[0].select('MF', server.app)
+        except CommandSetRegistrationError as e:
+            sys.stderr.write('ESIM: shell command registration broken after '
+                             're-initialization: %s\n' % e)
+            return False
+        except Exception as e:
+            sys.stderr.write('ESIM: post-equip MF select failed: %s\n' % e)
         sys.stderr.write('ESIM: re-initialized after profile switch\n')
         return True
     except Exception as e:

tests/test_esim.py

@@ -33,9 +33,11 @@ class FakeLchan:
     def __init__(self):
         self.scc = SimpleNamespace(name='lchan-scc')
         self.selected = None
+        self.cmd_app = None
 
-    def select_file(self, app):
+    def select_file(self, app, cmd_app=None):
         self.selected = app
+        self.cmd_app = cmd_app
 
 
 def make_app(profile='Consumer eUICC (SGP.22)', isdr=True):
@@ -46,13 +48,16 @@ def make_app(profile='Consumer eUICC (SGP.22)', isdr=True):
     rs = SimpleNamespace(profile=profile,
                          mf=SimpleNamespace(applications=apps),
                          lchan=[lchan],
-                         resets=0)
+                         resets=0,
+                         soft_reset_cmd_app=None)
 
-    def soft_reset():
+    def soft_reset(cmd_app=None):
         rs.resets += 1
+        rs.soft_reset_cmd_app = cmd_app
 
     rs.soft_reset = soft_reset
-    return SimpleNamespace(rs=rs), lchan
+    app = SimpleNamespace(rs=rs)
+    return app, lchan
 
 
 def profile_info(iccid, aid, state=None, nickname=None, cls=None, owner=None,
@@ -128,9 +133,12 @@ class EsimTests(unittest.TestCase):
         self.assertEqual(out['profiles'][1]['state'], 'disabled')
         self.assertIsNone(out['profiles'][1]['icon'])
         self.assertIsNone(out['profiles'][1]['icon_size'])
-        # ISD-R was selected and the previous selection restored
+        # ISD-R was selected (with the shell app, so pySim's command-set
+        # bookkeeping follows) and the previous selection restored the same way
         self.assertEqual(lchan.selected.name, 'ISD-R')
+        self.assertIs(lchan.cmd_app, app)
         self.assertEqual(app.rs.resets, 1)
+        self.assertIs(app.rs.soft_reset_cmd_app, app)
         # the request asks for every ProfileInfo tag
         self.assertIn('9F70', self.calls[0].to_tlv().hex().upper())
 
@@ -251,9 +259,12 @@ class EsimTests(unittest.TestCase):
         self.assertEqual(out['result'], 'ok')
         self.assertFalse(out['refresh_seen'])
         self.assertEqual(len(sent), 1)
-        # the ISD-R was selected for the command and the selection restored
+        # the ISD-R was selected for the command (with the shell app) and the
+        # selection restored the same way
         self.assertEqual(lchan.selected.name, 'ISD-R')
+        self.assertIs(lchan.cmd_app, app)
         self.assertEqual(app.rs.resets, 1)
+        self.assertIs(app.rs.soft_reset_cmd_app, app)
 
     def test_switch_profile_treats_91xx_as_ok_and_runs_the_chain(self):
         app, lchan = make_app()
@@ -268,7 +279,9 @@ class EsimTests(unittest.TestCase):
         self.assertTrue(out['refresh_seen'])
         self.assertEqual(chain, ['9111'])
         self.assertEqual(lchan.selected.name, 'ISD-R')
+        self.assertIs(lchan.cmd_app, app)
         self.assertEqual(app.rs.resets, 1)
+        self.assertIs(app.rs.soft_reset_cmd_app, app)
 
     def test_switch_profile_chain_failure_keeps_the_accepted_switch(self):
         app, _ = make_app()