accrual: Be case-insensitive when gathering payment-method.

This is a little nicer for the user, and lets us simplify surrounding
case-handling code.

conservancy_beancount/reports/accrual.py

@@ -482,10 +482,7 @@ class OutgoingReport(BaseReport):
         'uswire': 'Domestic Wire',
         'vendorportal': 'Vendor Portal',
     }
-    PAYMENT_METHOD_RE = re.compile(
-        rf'^([A-Z]{{3}})\s+({"|".join(PAYMENT_METHODS)})$',
-        re.IGNORECASE,
-    )
+    PAYMENT_METHOD_RE = re.compile(rf'^([a-z]{{3}})\s+({"|".join(PAYMENT_METHODS)})$')
 
     def __init__(self, rt_wrapper: rtutil.RT, out_file: TextIO) -> None:
         super().__init__(out_file)
@@ -579,20 +576,26 @@ class OutgoingReport(BaseReport):
             'payment-amount': payment_amount,
             'payment-to': payment_to,
         }
-        payment_methods = posts.meta_values('payment-method')
-        payment_methods.discard(None)
-        payment_method_count = len(payment_methods)
-        if payment_method_count != 1:
+        payment_methods = filters.iter_unique(
+            post.meta['payment-method'].lower()
+            for post in posts
+            if isinstance(post.meta.get('payment-method'), str)
+        )
+        payment_method: Optional[str] = next(payment_methods, None)
+        if payment_method is None:
+            payment_method_count = "no"
+        elif next(payment_methods, None) is None:
+            pass
+        else:
+            payment_method_count = "multiple"
+            payment_method = None
+        if payment_method is None:
             self.logger.warning(
                 "cannot set payment-method for rt:%s: %s metadata values found",
                 ticket_id, payment_method_count,
             )
         else:
-            payment_method = payment_methods.pop()
-            if isinstance(payment_method, str):
             match = self.PAYMENT_METHOD_RE.fullmatch(payment_method)
-            else:
-                match = None
             if match is None:
                 self.logger.warning(
                     "cannot set payment-method for rt:%s: invalid value %r",
@@ -601,7 +604,7 @@ class OutgoingReport(BaseReport):
             else:
                 cf_targets['payment-method'] = '{} {}'.format(
                     match.group(1).upper(),
-                    self.PAYMENT_METHODS[match.group(2).lower()],
+                    self.PAYMENT_METHODS[match.group(2)],
                 )
 
         cf_updates = {

setup.py

@@ -5,7 +5,7 @@ from setuptools import setup
 setup(
     name='conservancy_beancount',
     description="Plugin, library, and reports for reading Conservancy's books",
-    version='1.4.0',
+    version='1.4.1',
     author='Software Freedom Conservancy',
     author_email='info@sfconservancy.org',
     license='GNU AGPLv3+',