Add AR, AG, AB test case and fix behavior

client/ayon_core/lib/transcoding.py

@@ -389,7 +389,7 @@ def get_review_info_by_layer_name(channel_names):
             layer_names_order.append(layer_name)
 
         # R, G, B, A or X, Y, Z, N, AR, AG, AB
-        channel = last_part[0].upper()
+        channel = last_part.upper()
         channels_by_layer_name[layer_name][channel] = channel_name
 
     # Put empty layer to the beginning of the list

tests/client/ayon_core/lib/test_transcoding.py

@@ -82,6 +82,29 @@ class GetReviewInfoByLayerName(unittest.TestCase):
             }
         }])
 
+    def test_ar_ag_ab_channels(self):
+
+        info = get_review_info_by_layer_name(["AR", "AG", "AB"])
+        self.assertEqual(info, [{
+            "name": "",
+            "review_channels": {
+                "R": "AR",
+                "G": "AG",
+                "B": "AB",
+                "A": None,
+            }
+        }])
+
+        info = get_review_info_by_layer_name(["AR", "AG", "AB", "A"])
+        self.assertEqual(info, [{
+            "name": "",
+            "review_channels": {
+                "R": "AR",
+                "G": "AG",
+                "B": "AB",
+                "A": "A",
+            }
+        }])
 
     def test_unknown_channels(self):
         info = get_review_info_by_layer_name(["hello", "world"])