Fixing currency functions for german and french. Adding Currency_Forms for DE, FR and NL. (#247)

* Fix currency function for French. Adding Currency_Forms.

* Fix currency function for German. Adding Currency_Forms.

* Move FR_DZ to new currency functions, too.

* Fix tests

* Add more currency options for dutch.

* Add more tests for German, Dutch and French currencies.

num2words/lang_DE.py

@@ -23,6 +23,14 @@ from .lang_EU import Num2Word_EU
 
 
 class Num2Word_DE(Num2Word_EU):
+    CURRENCY_FORMS = {
+        'EUR': (('Euro', 'Euro'), ('Cent', 'Cent')),
+        'GBP': (('Pfund', 'Pfund'), ('Penny', 'Pence')),
+        'USD': (('Dollar', 'Dollar'), ('Cent', 'Cent')),
+        'CNY': (('Yuan', 'Yuan'), ('Jiao', 'Fen')),
+        'DEM': (('Mark', 'Mark'), ('Pfennig', 'Pfennig')),
+    }
+
     GIGA_SUFFIX = "illiarde"
     MEGA_SUFFIX = "illion"
 
@@ -134,22 +142,13 @@ class Num2Word_DE(Num2Word_EU):
         self.verify_ordinal(value)
         return str(value) + "."
 
-    def to_currency(self, val, longval=True, old=False):
-        hightxt = "Euro"
-        lowtxt = "Cent"
-        if old:
-            hightxt = "Mark"
-            lowtxt = "Pfennig/e"
-
-        cents = int(round(val*100))
-        res = self.to_splitnum(cents, hightxt=hightxt, lowtxt=lowtxt,
-                               jointxt="und", longval=longval)
-
+    def to_currency(self, val, currency='EUR', cents=True, separator=' und',
+                    adjective=False):
+        result = super(Num2Word_DE, self).to_currency(
+            val, currency=currency, cents=cents, separator=separator,
+            adjective=adjective)
         # Handle exception, in german is "ein Euro" and not "eins Euro"
-        if res.startswith("eins "):
-            res = res.replace("eins ", "ein ", 1)
-
-        return res
+        return result.replace("eins ", "ein ")
 
     def to_year(self, val, longval=True):
         if not (val // 100) % 10:

num2words/lang_FR.py

@@ -21,6 +21,14 @@ from .lang_EU import Num2Word_EU
 
 
 class Num2Word_FR(Num2Word_EU):
+    CURRENCY_FORMS = {
+        'EUR': (('euro', 'euros'), ('centime', 'centimes')),
+        'USD': (('dollar', 'dollars'), ('cent', 'cents')),
+        'FRF': (('franc', 'francs'), ('centime', 'centimes')),
+        'GBP': (('livre', 'livres'), ('penny', 'pence')),
+        'CNY': (('yuan', 'yuans'), ('fen', 'jiaos')),
+    }
+
     def setup(self):
         Num2Word_EU.setup(self)
 
@@ -92,10 +100,9 @@ class Num2Word_FR(Num2Word_EU):
         out += "er" if value == 1 else "me"
         return out
 
-    def to_currency(self, val, longval=True, old=False):
-        hightxt = "euro/s"
-        if old:
-            hightxt = "franc/s"
-        cents = int(round(val*100))
-        return self.to_splitnum(cents, hightxt=hightxt, lowtxt="centime/s",
-                                divisor=100, jointxt="et", longval=longval)
+    def to_currency(self, val, currency='EUR', cents=True, separator=' et',
+                    adjective=False):
+        result = super(Num2Word_FR, self).to_currency(
+            val, currency=currency, cents=cents, separator=separator,
+            adjective=adjective)
+        return result

num2words/lang_FR_DZ.py

@@ -21,8 +21,13 @@ from .lang_FR import Num2Word_FR
 
 
 class Num2Word_FR_DZ(Num2Word_FR):
-    def to_currency(self, val, longval=True, cents=True, jointxt="virgule"):
-        return self.to_splitnum(
-            val, hightxt="dinard/s", lowtxt="centime/s", divisor=1,
-            jointxt=jointxt, longval=longval, cents=cents
-        )
+    CURRENCY_FORMS = {
+        'DIN': (('dinard', 'dinards'), ('centime', 'centimes')),
+    }
+
+    def to_currency(self, val, currency='DIN', cents=True, separator=' et',
+                    adjective=False):
+        result = super(Num2Word_FR, self).to_currency(
+            val, currency=currency, cents=cents, separator=separator,
+            adjective=adjective)
+        return result

num2words/lang_NL.py

@@ -22,7 +22,10 @@ from .lang_EU import Num2Word_EU
 
 class Num2Word_NL(Num2Word_EU):
     CURRENCY_FORMS = {
-        'EUR': (('euro', 'euros'), ('cent', 'cents')),
+        'EUR': (('euro', 'euro'), ('cent', 'cent')),
+        'GBP': (('pond', 'pond'), ('penny', 'pence')),
+        'USD': (('dollar', 'dollar'), ('cent', 'cent')),
+        'CNY': (('yuan', 'yuan'), ('jiao', 'fen')),
     }
 
     GIGA_SUFFIX = "iljard"