Add minimum classes concept to the StudentGradeCalculator

Author: JavierCane

examples/java/java-student_grades-01_base_example/src/main/java/tv/codely/student_grades/StudentGradeCalculator.java

@@ -3,7 +3,7 @@
 import java.util.List;
 
 public class StudentGradeCalculator {
-    public Float calculateGrades(final List<Float> examsGrades) {
+    public Float calculateGrades(final List<Float> examsGrades, final Boolean hasReachedMinimumClasses) {
         if (!examsGrades.isEmpty()) {
             Float gradesSum = 0.f;
             Integer gradesCounter = 0;
@@ -13,7 +13,11 @@ public Float calculateGrades(final List<Float> examsGrades) {
                 gradesCounter++;
             }
 
-            return gradesSum / gradesCounter;
+            if (hasReachedMinimumClasses) {
+                return gradesSum / gradesCounter;
+            } else {
+                return 0.f;
+            }
         } else {
             return 0.f;
         }

examples/java/java-student_grades-01_base_example/src/test/java/tv/codely/student_grades/StudentGradeCalculatorShould.java

@@ -9,39 +9,85 @@
 
 public class StudentGradeCalculatorShould {
 
-	@Test
-	void calculate_0_with_no_exam_grades() {
-		StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+    @Test
+    void fail_given_there_are_no_exams() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
 
-        final List<Float> examsGrades = Collections.emptyList();
+        final List<Float> examsGrades              = Collections.emptyList();
+        final Boolean     hasReachedMinimumClasses = true;
 
-        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades));
-	}
+        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
 
-	@Test
-	void calculate_same_grade_with_one_single_exam() {
-		StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+    @Test
+    void calculate_same_grade_given_one_single_exam_and_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
 
-        final List<Float> examsGrades = List.of(5.f);
+        final List<Float> examsGrades              = List.of(5.f);
+        final Boolean     hasReachedMinimumClasses = true;
 
-        assertEquals(5, studentGradeCalculator.calculateGrades(examsGrades));
-	}
+        assertEquals(5, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
 
-	@Test
-	void calculate_average_grade_based_on_different_exam_grades() {
-		StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+    @Test
+    void calculate_average_grade_given_different_exam_grades_and_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
 
-        final List<Float> examsGrades = List.of(5.f, 4.f, 6.f, 2.f, 8.f, 0.f, 10.f);
+        final List<Float> examsGrades              = List.of(5.f, 4.f, 6.f, 2.f, 8.f, 0.f, 10.f);
+        final Boolean     hasReachedMinimumClasses = true;
 
-        assertEquals(5, studentGradeCalculator.calculateGrades(examsGrades));
-	}
+        assertEquals(5, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
 
-	@Test
-	void round_up_to_2_decimals() {
-		StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+    @Test
+    void round_up_to_2_decimals_given_odd_exam_grades_and_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
 
-        final List<Float> examsGrades = List.of(5.f, 4.f);
+        final List<Float> examsGrades              = List.of(5.f, 4.f);
+        final Boolean     hasReachedMinimumClasses = true;
 
-        assertEquals(4.5f, studentGradeCalculator.calculateGrades(examsGrades));
-	}
+        assertEquals(4.5f, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
+
+    // hasReachedMinimumClasses
+
+    @Test
+    void fail_when_there_are_no_exams_and_has_not_attended_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+
+        final List<Float> examsGrades              = Collections.emptyList();
+        final Boolean     hasReachedMinimumClasses = false;
+
+        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
+
+    @Test
+    void fail_given_one_single_exam_but_not_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+
+        final List<Float> examsGrades              = List.of(5.f);
+        final Boolean     hasReachedMinimumClasses = false;
+
+        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
+
+    @Test
+    void fail_given_different_exam_grades_but_not_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+
+        final List<Float> examsGrades              = List.of(5.f, 4.f, 6.f, 2.f, 8.f, 0.f, 10.f);
+        final Boolean     hasReachedMinimumClasses = false;
+
+        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
+
+    @Test
+    void fail_given_odd_exam_grades_but_not_attending_the_minimum_classes() {
+        StudentGradeCalculator studentGradeCalculator = new StudentGradeCalculator();
+
+        final List<Float> examsGrades              = List.of(5.f, 4.f);
+        final Boolean     hasReachedMinimumClasses = false;
+
+        assertEquals(0, studentGradeCalculator.calculateGrades(examsGrades, hasReachedMinimumClasses));
+    }
 }