fix export of ledger commodities to ledger (#215)

- add is_currency() to Commodity
- do not add the "check commodity" in ledger export if commodity is not a currency
- properly escape commodity names

piecash/core/commodity.py

@@ -77,9 +77,7 @@ class Price(DeclarativeBaseGuid):
  foreign_keys=[currency_guid],
  )
 
- def __init__(
- self, commodity, currency, date, value, type="unknown", source="user:price"
- ):
+ def __init__(self, commodity, currency, date, value, type="unknown", source="user:price"):
  self.commodity = commodity
  self.currency = currency
  assert _type(date) is datetime.date
@@ -89,9 +87,7 @@ def __init__(
  self.source = source
 
  def __str__(self):
- return "Price<{:%Y-%m-%d} : {} {}/{}>".format(
- self.date, self.value, self.currency.mnemonic, self.commodity.mnemonic
- )
+ return "Price<{:%Y-%m-%d} : {} {}/{}>".format(self.date, self.value, self.currency.mnemonic, self.commodity.mnemonic)
 
  def object_to_validate(self, change):
  if change[-1] != "deleted":
@@ -159,9 +155,7 @@ class Commodity(DeclarativeBaseGuid):
  def base_currency(self):
  b = self.book
  if b is None:
- raise GnucashException(
- "The commodity should be linked to a session to have a 'base_currency'"
- )
+ raise GnucashException("The commodity should be linked to a session to have a 'base_currency'")
 
  if self.namespace == "CURRENCY":
  # get the base currency as first commodity in DB
@@ -238,6 +232,9 @@ def __str__(self):
  def precision(self):
  return len(str(self.fraction)) - 1
 
+ def is_currency(self):
+ return self.namespace == "CURRENCY"
+
  def currency_conversion(self, currency):
  """
  Return the latest conversion factor to convert self to currency
@@ -253,16 +250,12 @@ def currency_conversion(self, currency):
 
  """
  # conversion is done from self.commodity to commodity (if possible)
- sc2c = (
- self.prices.filter_by(currency=currency).order_by(Price.date.desc()).first()
- )
+ sc2c = self.prices.filter_by(currency=currency).order_by(Price.date.desc()).first()
  if sc2c:
  return sc2c.value
 
  # conversion is done directly from commodity to self.commodity (if possible)
- c2sc = (
- currency.prices.filter_by(currency=self).order_by(Price.date.desc()).first()
- )
+ c2sc = currency.prices.filter_by(currency=self).order_by(Price.date.desc()).first()
  if c2sc:
  return Decimal(1) / c2sc.value
 
@@ -285,9 +278,7 @@ def update_prices(self, start_date=None):
  .. todo:: add some frequency to retrieve prices only every X (week, month, ...)
  """
  if self.book is None:
- raise GncPriceError(
- "Cannot update price for a commodity not attached to a book"
- )
+ raise GncPriceError("Cannot update price for a commodity not attached to a book")
 
  # get last_price updated
  last_price = self.prices.order_by(Price.date.desc()).limit(1).first()
@@ -298,7 +289,7 @@ def update_prices(self, start_date=None):
  if last_price:
  start_date = max(last_price.date + datetime.timedelta(days=1), start_date)
 
- if self.namespace == "CURRENCY":
+ if self.is_currency():
  # get reference currency (from book.root_account)
  default_currency = self.base_currency
  if default_currency == self:
@@ -337,8 +328,6 @@ def object_to_validate(self, change):
  def validate(self):
  # check uniqueness of namespace/mnemonic
  try:
- self.book.query(Commodity).filter_by(
- namespace=self.namespace, mnemonic=self.mnemonic
- ).one()
+ self.book.query(Commodity).filter_by(namespace=self.namespace, mnemonic=self.mnemonic).one()
  except MultipleResultsFound:
  raise ValueError("{} already exists in this book".format(self))