Choose ordinal suffixes from the absolute value.

Negative integers use a non-negative remainder in Python, so -21 was rendered as -21th instead of -21st.

Author: fhgffy

src/humanize/number.py

@@ -136,7 +136,10 @@ def ordinal(value: NumberOrString, gender: str = "male") -> str:
     except (TypeError, ValueError):
         return str(value)
     gender = "male" if gender == "male" else "female"
-    digit = 0 if value % 100 in (11, 12, 13) else value % 10
+    # Suffixes follow the absolute value. Python's % on a negative number
+    # is not the last digit, so -21 used to render as "-21th".
+    suffix_value = abs(value)
+    digit = 0 if suffix_value % 100 in (11, 12, 13) else suffix_value % 10
     return f"{value}{P_(*_ORDINAL_SUFFIXES[gender][digit])}"
 
 

tests/test_number.py

@@ -25,6 +25,17 @@
         ("102", "102nd"),
         ("103", "103rd"),
         ("111", "111th"),
+        (-1, "-1st"),
+        (-2, "-2nd"),
+        (-3, "-3rd"),
+        (-11, "-11th"),
+        (-12, "-12th"),
+        (-13, "-13th"),
+        (-21, "-21st"),
+        (-22, "-22nd"),
+        (-23, "-23rd"),
+        (-101, "-101st"),
+        (-111, "-111th"),
         ("something else", "something else"),
         (None, "None"),
         (math.nan, "NaN"),