meta_receipt: Accept invoice in lieu of receipt for credit card charges.

conservancy_beancount/plugin/meta_receipt.py

@@ -38,21 +38,25 @@ class MetaReceipt(core._RequireLinksPostingMetadataHook):
     def post_run(self, txn: Transaction, post: data.Posting) -> errormod.Iter:
         try:
             self._check_links(txn, post, 'receipt')
-        except errormod.Error as receipt_error:
+        except errormod.Error as error:
-            # Outgoing check may omit a receipt if they have a check link
+            receipt_error = error
-            # instead.
-            if ':Check' not in post.account:
-                yield receipt_error
         else:
+            return
+        if post.account.is_checking():
+            fallback_key = 'check'
+        elif (post.account.is_under('Liabilities:CreditCard')
+              and (post.units.number or 0) < 0):
+            fallback_key = 'invoice'
+        else:
+            yield receipt_error
+            return
         try:
-                    self._check_links(txn, post, 'check')
+            self._check_links(txn, post, fallback_key)
-                except errormod.Error as check_error:
+        except errormod.Error as fallback_error:
-                    if (receipt_error.message.endswith(" missing receipt")
+            if (receipt_error.message.endswith(f" missing {self.METADATA_KEY}")
-                        and check_error.message.endswith(" missing check")):
+                and fallback_error.message.endswith(f" missing {fallback_key}")):
-                        check_error.message = check_error.message.replace(
+                receipt_error.message += f" or {fallback_key}"
-                            " missing check", " missing receipt or check",
+                yield receipt_error
-                        )
-                        yield check_error
             else:
                 yield receipt_error
-                        yield check_error
+                yield fallback_error

tests/test_meta_receipt.py

@@ -60,6 +60,8 @@ ACCOUNTS = [AccountForTesting._make(t) for t in [
     ('Assets:Cash', PostType.BOTH, None),
     ('Assets:Checking', PostType.BOTH, 'check'),
     ('Assets:Savings', PostType.BOTH, None),
+    ('Liabilities:CreditCard', PostType.CREDIT, None),
+    ('Liabilities:CreditCard', PostType.DEBIT, 'invoice'),
 ]]
 
 ACCOUNTS_WITH_FALLBACKS = [acct for acct in ACCOUNTS if acct.fallback_meta]