Money, Rate, CentCount and a bunch of bugfixes.

1 files changed, 89 insertions, 0 deletions

diff --git a/type/rate.py b/type/rate.py
new file mode 100644
index 0000000..3161131
--- /dev/null
+++ b/type/rate.py
@@ -0,0 +1,89 @@
+#!/usr/bin/env python3
+
+from typing import Optional
+
+
+class Rate(object):
+    def __init__(
+            self,
+            multiplier: Optional[float] = None,
+            *,
+            percentage: Optional[float] = None,
+            percent_change: Optional[float] = None,
+    ):
+        count = 0
+        if multiplier is not None:
+            if isinstance(multiplier, str):
+                multiplier = multiplier.replace('%', '')
+                m = float(multiplier)
+                m /= 100
+                self.multiplier = m
+            else:
+                self.multiplier = multiplier
+            count += 1
+        if percentage is not None:
+            self.multiplier = percentage / 100
+            count += 1
+        if percent_change is not None:
+            self.multiplier = 1.0 + percent_change / 100
+            count += 1
+        if count != 1:
+            raise Exception(
+                'Exactly one of percentage, percent_change or multiplier is required.'
+            )
+
+    def apply_to(self, other):
+        return self.__mul__(other)
+
+    def of(self, other):
+        return self.__mul__(other)
+
+    def __float__(self):
+        return self.multiplier
+
+    def __mul__(self, other):
+        return self.multiplier * float(other)
+
+    __rmul__ = __mul__
+
+    def __truediv__(self, other):
+        return self.multiplier / float(other)
+
+    def __add__(self, other):
+        return self.multiplier + float(other)
+
+    __radd__ = __add__
+
+    def __sub__(self, other):
+        return self.multiplier - float(other)
+
+    def __eq__(self, other):
+        return self.multiplier == float(other)
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+    def __lt__(self, other):
+        return self.multiplier < float(other)
+
+    def __gt__(self, other):
+        return self.multiplier > float(other)
+
+    def __le__(self, other):
+        return self < other or self == other
+
+    def __ge__(self, other):
+        return self > other or self == other
+
+    def __hash__(self):
+        return self.multiplier
+
+    def __repr__(self,
+                 *,
+                 relative=False,
+                 places=3):
+        if relative:
+            percentage = (self.multiplier - 1.0) * 100.0
+        else:
+            percentage = self.multiplier * 100.0
+        return f'{percentage:+.{places}f}%'