Moved the logic in the make_txn_form_from_post() utility to the constructor of the transaction form, and moved the logic in the make_txn_form_from_status() utility to the txn_form view, and applied the standardized control flow to the txn_form view in the accounting application.

accounting/forms.py

@@ -34,7 +34,7 @@ class RecordForm(forms.Form):
     """An accounting record form.
 
     Attributes:
-        transaction (Transaction|None): The current transaction or None.
+        txn_form (TransactionForm): The parent transaction form.
         is_credit (bool): Whether this is a credit record.
     """
     id = forms.IntegerField(
@@ -64,7 +64,7 @@ class RecordForm(forms.Form):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self.transaction = None
+        self.txn_form = None
         self.is_credit = None
 
     def account_title(self):
@@ -109,7 +109,7 @@ class RecordForm(forms.Form):
         """
         if "id" in self.errors:
             return
-        if self.transaction is None:
+        if self.txn_form.transaction is None:
             if "id" in self.data:
                 raise forms.ValidationError(
                     _("This record is not for this transaction."),
@@ -117,7 +117,7 @@ class RecordForm(forms.Form):
         else:
             if "id" in self.data:
                 record = Record.objects.get(pk=self.data["id"])
-                if record.transaction.pk != self.transaction.pk:
+                if record.transaction.pk != self.txn_form.transaction.pk:
                     raise forms.ValidationError(
                         _("This record is not for this transaction."),
                         code="not_belong")
@@ -192,10 +192,45 @@ class TransactionForm(forms.Form):
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        self.txn_type = None
+        # Populates the belonging record forms
-        self.transaction = None
         self.debit_records = []
         self.credit_records = []
+        if len(args) > 0 and isinstance(args[0], dict):
+            by_rec_id = {}
+            for key in args[0].keys():
+                m = re.match(
+                    ("^((debit|credit)-([1-9][0-9]*))-"
+                     "(id|ord|account|summary|amount)$"),
+                    key)
+                if m is None:
+                    continue
+                rec_id = m.group(1)
+                column = m.group(4)
+                if rec_id not in by_rec_id:
+                    by_rec_id[rec_id] = {
+                        "is_credit": m.group(2) == "credit",
+                        "no": int(m.group(3)),
+                        "data": {},
+                    }
+                by_rec_id[rec_id]["data"][column] = args[0][key]
+            debit_data_list = [x for x in by_rec_id.values()
+                               if not x["is_credit"]]
+            debit_data_list.sort(key=lambda x: x["no"])
+            for x in debit_data_list:
+                record_form = RecordForm(x["data"])
+                record_form.txn_form = self
+                record_form.is_credit = False
+                self.debit_records.append(record_form)
+            credit_data_list = [x for x in by_rec_id.values()
+                                if x["is_credit"]]
+            credit_data_list.sort(key=lambda x: x["no"])
+            for x in credit_data_list:
+                record_form = RecordForm(x["data"])
+                record_form.txn_form = self
+                record_form.is_credit = True
+                self.credit_records.append(record_form)
+        self.txn_type = None
+        self.transaction = None
 
     def clean(self):
         """Validates the form globally.

accounting/utils.py

@@ -641,7 +641,7 @@ def make_txn_form_from_model(txn_type, txn):
         except ObjectDoesNotExist:
             pass
         record_form = RecordForm(data)
-        record_form.transaction = form.transaction
+        record_form.txn_form = form
         record_form.is_credit = record.is_credit
         if record.is_credit:
             form.credit_records.append(record_form)
@@ -650,62 +650,6 @@ def make_txn_form_from_model(txn_type, txn):
     return form
 
 
-def make_txn_form_from_post(post, txn_type, txn):
-    """Converts the POSTed data to a transaction form.
-
-    Args:
-        post (dict[str]): The POSTed data.
-        txn_type (str): The transaction type.
-        txn (Transaction|None): The current transaction, or None
-            if there is no current transaction.
-
-    Returns:
-        TransactionForm: The transaction form.
-    """
-    form = TransactionForm(
-        {x: post[x] for x in ("date", "notes") if x in post})
-    form.transaction = txn
-    form.txn_type = txn_type
-    # The records
-    max_no = _find_max_record_no(txn_type, post)
-    for record_type in max_no.keys():
-        records = []
-        is_credit = (record_type == "credit")
-        for i in range(max_no[record_type]):
-            no = i + 1
-            record_form = RecordForm(
-                {x: post[F"{record_type}-{no}-{x}"]
-                 for x in ["id", "account", "summary", "amount"]
-                 if F"{record_type}-{no}-{x}" in post})
-            record_form.transaction = form.transaction
-            record_form.is_credit = is_credit
-            records.append(record_form)
-        if record_type == "debit":
-            form.debit_records = records
-        else:
-            form.credit_records = records
-    return form
-
-
-def make_txn_form_from_status(request, txn_type, txn):
-    """Converts the previously-stored status to a transaction form.
-
-    Args:
-        request (HttpRequest): The request.
-        txn_type (str): The transaction type.
-        txn (Transaction|None): The current transaction, or None
-            if there is no current transaction.
-
-    Returns:
-        TransactionForm: The transaction form, or None if there is no
-            previously-stored status.
-    """
-    form = stored_post.get_previous_post(request)
-    if form is None:
-        return None
-    return make_txn_form_from_post(form, txn_type, txn)
-
-
 def _find_max_record_no(txn_type, post):
     """Finds the max debit and record numbers from the POSTed form.
 

accounting/views.py

@@ -820,14 +820,17 @@ def txn_form(request, txn_type, txn=None):
     Returns:
         HttpResponse: The response.
     """
-    form = utils.make_txn_form_from_status(request, txn_type, txn)
+    previous_post = stored_post.get_previous_post(request)
-    if form is None:
+    if previous_post is not None:
-        if txn is None:
+        form = TransactionForm(previous_post)
+    elif txn is not None:
+        form = utils.make_txn_form_from_model(txn_type, txn)
+    else:
         form = TransactionForm()
         form.debit_records.append(RecordForm())
         form.credit_records.append(RecordForm())
-        else:
+    form.transaction = txn
-            form = utils.make_txn_form_from_model(txn_type, txn)
+    form.txn_type = txn_type
     new_record_context = {"record": RecordForm(),
                           "record_type": "TTT",
                           "no": "NNN",
@@ -863,7 +866,10 @@ def txn_store(request, txn_type, txn=None):
     post = request.POST.dict()
     strip_post(post)
     utils.sort_post_txn_records(post)
-    form = utils.make_txn_form_from_post(post, txn_type, txn)
+    form = TransactionForm(post)
+    form.transaction = txn
+    form.txn_type = txn_type
+    #form = utils.make_txn_form_from_post(post, txn_type, txn)
     if not form.is_valid():
         if txn is None:
             url = reverse("accounting:transactions.create", args=(txn_type,))