test: gate the bitcoin-only suite on the bitcoin-only product

tests/common.py

@@ -194,5 +194,18 @@ def requires_fullFeature(self):
             self.client.features.firmware_variant == "EmulatorBTC":
         self.skipTest("Full feature firmware required to run this test")
 
+    def requires_bitcoinOnly(self):
+      """Inverse of requires_fullFeature(): skip unless this IS the
+      bitcoin-only product.
+
+      Usable since the firmware learned to report the variant honestly --
+      variant_getName() used to answer "Emulator" for both products, so a
+      bitcoin-only emulator was indistinguishable from a full one and this
+      guard could not be written.
+      """
+      if self.client.features.firmware_variant not in ("KeepKeyBTC",
+                                                       "EmulatorBTC"):
+        self.skipTest("Bitcoin-only firmware required to run this test")
+
 
 

tests/test_msg_bitcoin_only_variant.py

@@ -100,6 +100,12 @@ class TestBitcoinOnlyVariant(common.KeepKeyTest):
     def setUp(self):
         super(TestBitcoinOnlyVariant, self).setUp()
         self.requires_firmware("7.15.0")
+        # This whole file describes the BITCOIN-ONLY product. Several tests
+        # assert screen sequences that differ on the multi-chain build -- the
+        # OP_RETURN one decodes a THORChain memo there and draws more screens --
+        # so running them against a full-feature device is a category error, not
+        # a finding. CI points the pyk suite at the full emulator image.
+        self.requires_bitcoinOnly()
         self.screens = []
         # Refuse (press NO) on the Nth ButtonRequest of the current flow;
         # None means confirm everything.