gh-100488: Add is_integer method to fractions.Fraction (#100489)

2 files changed, 17 insertions, 0 deletions

diff --git a/Lib/fractions.py b/Lib/fractions.py
index 75c7df1..4302f3f 100644
--- a/Lib/fractions.py
+++ b/Lib/fractions.py
@@ -225,6 +225,10 @@ class Fraction(numbers.Rational):
                 (cls.__name__, dec, type(dec).__name__))
         return cls(*dec.as_integer_ratio())
 
+    def is_integer(self):
+        """Return True if the Fraction is an integer."""
+        return self._denominator == 1
+
     def as_integer_ratio(self):
         """Return the integer ratio as a tuple.
 
diff --git a/Lib/test/test_fractions.py b/Lib/test/test_fractions.py
index 7fa9dbe..819d680 100644
--- a/Lib/test/test_fractions.py
+++ b/Lib/test/test_fractions.py
@@ -340,6 +340,19 @@ class FractionTest(unittest.TestCase):
             ValueError, "cannot convert NaN to integer ratio",
             F.from_decimal, Decimal("snan"))
 
+    def test_is_integer(self):
+        self.assertTrue(F(1, 1).is_integer())
+        self.assertTrue(F(-1, 1).is_integer())
+        self.assertTrue(F(1, -1).is_integer())
+        self.assertTrue(F(2, 2).is_integer())
+        self.assertTrue(F(-2, 2).is_integer())
+        self.assertTrue(F(2, -2).is_integer())
+
+        self.assertFalse(F(1, 2).is_integer())
+        self.assertFalse(F(-1, 2).is_integer())
+        self.assertFalse(F(1, -2).is_integer())
+        self.assertFalse(F(-1, -2).is_integer())
+
     def test_as_integer_ratio(self):
         self.assertEqual(F(4, 6).as_integer_ratio(), (2, 3))
         self.assertEqual(F(-4, 6).as_integer_ratio(), (-2, 3))