Add "number to word" tests & forbid too small/big numbers

src/api/parsers.py

@@ -47,7 +47,7 @@ def parse_name(name: str) -> str:
                 parsed_name += char
         elif char.isdigit():
             num_digits = len([c for c in name if c.isdigit()])  # greedily get digits
-            word = Helpers.digit_str_to_word(name[:num_digits])
+            word = Helpers.number_to_word(int(name[:num_digits]))
             if parsed_name != "":
                 word = Helpers.capitalize(word)
             parsed_name += word

src/application/helpers.py

@@ -68,20 +68,3 @@ def number_to_word(cls, number: int) -> str:
     @classmethod
     def capitalize(cls, s: str) -> str:
         return s[0].upper() + s[1:]
-
-    @classmethod
-    def digit_str_to_word(cls, digits_str: str) -> str:
-        """Converts a string of digits to a word.
-
-        For example, "123" -> "oneHundredTwentyThree",
-        "911" -> "nineHundredEleven".
-        """
-        num_digits = len(digits_str)
-        if num_digits <= 3:
-            return cls.number_to_word(int(digits_str))
-
-        word = cls.number_to_word(int(digits_str[0]))
-        for i in range(1, num_digits):
-            tmp = Helpers.number_to_word(int(digits_str[i]))
-            word += Helpers.capitalize(tmp)
-        return word

tests/number_word_test.py

@@ -0,0 +1,30 @@
+from application.helpers import Helpers
+
+import pytest
+
+
+class TestNumberWord:
+    @pytest.mark.parametrize(
+        "input, expected",
+        [
+            (1, "one"),
+            (2, "two"),
+            (3, "three"),
+            (10, "ten"),
+            (18, "eighteen"),
+            (76, "seventySix"),
+            (100, "oneHundred"),
+            (101, "oneHundredOne"),
+            (123, "oneHundredTwentyThree"),
+            (305, "threeHundredFive"),
+            (911, "nineHundredEleven"),
+            (999, "nineHundredNinetyNine"),
+        ],
+    )
+    def test_number_to_word(self, input, expected):
+        assert Helpers.number_to_word(input) == expected
+
+    @pytest.mark.parametrize("input", [1000, 1001, -1, -500])
+    def test_number_to_word_raises(self, input):
+        with pytest.raises(ValueError, match="numbers between 0 and 999"):
+            Helpers.number_to_word(input)