fix #3912: Use Decimal('NaN') instead of None when exchange rate is not available.

lib/exchange_rate.py

@@ -109,8 +109,8 @@ class ExchangeBase(PrintError):
 
     def historical_rate(self, ccy, d_t):
         if d_t is None:
-            return None
-        return self.history.get(ccy, {}).get(d_t.strftime('%Y-%m-%d'))
+            return 'NaN'
+        return self.history.get(ccy, {}).get(d_t.strftime('%Y-%m-%d'), 'NaN')
 
     def get_currencies(self):
         rates = self.get_rates('')
@@ -497,40 +497,38 @@ class FxThread(ThreadJob):
     def exchange_rate(self):
         '''Returns None, or the exchange rate as a Decimal'''
         rate = self.exchange.quotes.get(self.ccy)
-        if rate:
-            return Decimal(rate)
+        if rate is None:
+            return Decimal('NaN')
+        return Decimal(rate)
 
     def format_amount_and_units(self, btc_balance):
         rate = self.exchange_rate()
-        return '' if rate is None else "%s %s" % (self.value_str(btc_balance, rate), self.ccy)
+        return '' if rate.is_nan() else "%s %s" % (self.value_str(btc_balance, rate), self.ccy)
 
     def get_fiat_status_text(self, btc_balance, base_unit, decimal_point):
         rate = self.exchange_rate()
-        return _("  (No FX rate available)") if rate is None else " 1 %s~%s %s" % (base_unit,
+        return _("  (No FX rate available)") if rate.is_nan() else " 1 %s~%s %s" % (base_unit,
             self.value_str(COIN / (10**(8 - decimal_point)), rate), self.ccy)
 
     def value_str(self, satoshis, rate):
-        if satoshis is not None and rate is not None:
-            value = Decimal(satoshis) / COIN * Decimal(rate)
-        else:
-            value = None
+        value = Decimal('NaN') if satoshis is None else Decimal(satoshis) / COIN * Decimal(rate)
         return self.format_fiat(value)
 
     def format_fiat(self, value):
-        if value is not None:
-            return "%s" % (self.ccy_amount_str(value, True))
-        return _("No data")
+        if value.is_nan():
+            return _("No data")
+        return "%s" % (self.ccy_amount_str(value, True))
 
     def history_rate(self, d_t):
         if d_t is None:
-            return None
+            return Decimal('NaN')
         rate = self.exchange.historical_rate(self.ccy, d_t)
         # Frequently there is no rate for today, until tomorrow :)
         # Use spot quotes in that case
-        if rate is None and (datetime.today().date() - d_t.date()).days <= 2:
-            rate = self.exchange.quotes.get(self.ccy)
+        if rate == 'NaN' and (datetime.today().date() - d_t.date()).days <= 2:
+            rate = self.exchange.quotes.get(self.ccy, 'NaN')
             self.history_used_spot = True
-        return Decimal(rate) if rate is not None else None
+        return Decimal(rate)
 
     def historical_value_str(self, satoshis, d_t):
         rate = self.history_rate(d_t)
@@ -538,8 +536,7 @@ class FxThread(ThreadJob):
 
     def historical_value(self, satoshis, d_t):
         rate = self.history_rate(d_t)
-        if rate:
-            return Decimal(satoshis) / COIN * Decimal(rate)
+        return Decimal(satoshis) / COIN * Decimal(rate)
 
     def timestamp_rate(self, timestamp):
         from electrum.util import timestamp_to_datetime

lib/wallet.py

@@ -958,6 +958,7 @@ class Abstract_Wallet(PrintError):
         # return last balance
         return balance
 
+    @profiler
     def get_full_history(self, domain=None, from_timestamp=None, to_timestamp=None, fx=None, show_addresses=False):
         from .util import timestamp_to_datetime, Satoshis, Fiat
         out = []
@@ -1016,11 +1017,10 @@ class Abstract_Wallet(PrintError):
                 item['fiat_default'] = fiat_default
                 if value < 0:
                     ap, lp = self.capital_gain(tx_hash, fx.timestamp_rate, fx.ccy)
-                    cg = None if lp is None or ap is None else lp - ap
+                    cg = lp - ap
                     item['acquisition_price'] = Fiat(ap, fx.ccy)
                     item['capital_gain'] = Fiat(cg, fx.ccy)
-                    if cg is not None:
-                        capital_gains += cg
+                    capital_gains += cg
                 else:
                     if fiat_value is not None:
                         fiat_income += fiat_value
@@ -1686,11 +1686,9 @@ class Abstract_Wallet(PrintError):
         coins = self.get_utxos(domain)
         now = time.time()
         p = price_func(now)
-        if p is None:
-            return
         ap = sum(self.coin_price(coin, price_func, ccy, self.txin_value(coin)) for coin in coins)
         lp = sum([coin['value'] for coin in coins]) * p / Decimal(COIN)
-        return None if ap is None or lp is None else lp - ap
+        return lp - ap
 
     def capital_gain(self, txid, price_func, ccy):
         """
@@ -1704,13 +1702,11 @@ class Abstract_Wallet(PrintError):
         fiat_value = self.get_fiat_value(txid, ccy)
         if fiat_value is None:
             p = self.price_at_timestamp(txid, price_func)
-            liquidation_price = None if p is None else out_value/Decimal(COIN) * p
+            liquidation_price = out_value/Decimal(COIN) * p
         else:
             liquidation_price = - fiat_value
-        try:
-            acquisition_price = out_value/Decimal(COIN) * self.average_price(tx, price_func, ccy)
-        except:
-            acquisition_price = None
+
+        acquisition_price = out_value/Decimal(COIN) * self.average_price(tx, price_func, ccy)
         return acquisition_price, liquidation_price
 
     def average_price(self, tx, price_func, ccy):
@@ -1731,10 +1727,10 @@ class Abstract_Wallet(PrintError):
                 return fiat_value
             else:
                 p = self.price_at_timestamp(txid, price_func)
-                return None if p is None else p * txin_value/Decimal(COIN)
+                return p * txin_value/Decimal(COIN)
         else:
             # could be some coinjoin transaction..
-            return None
+            return Decimal('NaN')
 
 
 class Simple_Wallet(Abstract_Wallet):