score implementation refactoring for the incomplete frames test

src/main/java/BowlingGameCalculator.java

@@ -2,9 +2,13 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 public class BowlingGameCalculator {
+
+    private static final Pattern SINGLE_VALUE_PATTERN = Pattern.compile("\\d");
+    private static final int INITIAL_SCORE_VALUE = 0;
+
     public int score(String playerResult) {
-        Matcher singleDigit = Pattern.compile("\\d").matcher(playerResult);
-        int playerScore = 0;
+        Matcher singleDigit = SINGLE_VALUE_PATTERN.matcher(playerResult);
+        int playerScore = INITIAL_SCORE_VALUE;
         while (singleDigit.find()) {
             playerScore += Integer.parseInt(singleDigit.group());
         }

src/test/java/BowlingCalculatorTest.java

@@ -21,7 +21,8 @@ public class BowlingCalculatorTest {
     private static Stream<Arguments> playerResults() {
         return Stream.of(
                 Arguments.of("worst game", "0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0", 0),   // 20x 0
-                Arguments.of("some incomplete frames", "0,1,2,3,0,0,4,0,0,5,0,0,6,0,0,0,0,0,0,0", 21)
+                Arguments.of("some incomplete frames", "0,1,2,3,0,0,4,0,0,5,0,0,6,0,0,0,0,0,0,0", 21),
+                Arguments.of("some other incomplete frames", "9- 9- 9- 9- 9- 9- 9- 9- 9- 9-", 90)
         );
     }
 }