Simplify lambda statements

Author: arunp

src/test/java/org/example/LeapYearCalculatorSpec.java

@@ -56,7 +56,7 @@ class A_year_is_supported {
         @ValueSource(ints = { 1, Integer.MAX_VALUE })
         void if_it_is_positive(int year) {
             thenNoException()
-                .isThrownBy(() -> { isLeapYear(year); });
+                .isThrownBy(() -> isLeapYear(year));
         }
 
     }
@@ -69,15 +69,15 @@ class A_year_is_not_supported {
         void if_it_is_zero() {
             thenExceptionOfType
                 (IllegalArgumentException.class)
-                .isThrownBy(() -> { isLeapYear(0); });
+                .isThrownBy(() -> isLeapYear(0));
         }
 
         @ParameterizedTest
         @ValueSource(ints = { -1, -4, -100, -400, Integer.MIN_VALUE })
         void if_it_is_negative(int year) {
             thenExceptionOfType
                     (IllegalArgumentException.class)
-                    .isThrownBy(() -> { isLeapYear(year); });
+                    .isThrownBy(() -> isLeapYear(year));
         }
 
     }

src/test/java/org/example/QueueSpecTests.java

@@ -34,15 +34,15 @@ void preserves_positive_bounding_capacity() {
         void rejects_a_zero_bounding_capacity() {
             thenExceptionOfType
                 (IllegalArgumentException.class)
-                    .isThrownBy(() -> { new Queue<>(0); });
+                    .isThrownBy(() -> new Queue<>(0));
 
         }
 
         @Test
         void rejects_a_negative_bounding_capacity() {
             thenExceptionOfType
                 (IllegalArgumentException.class)
-                    .isThrownBy(() -> { new Queue<>(-1); });
+                    .isThrownBy(() -> new Queue<>(-1));
 
         }
 

src/test/java/org/example/StackTests.java

@@ -30,14 +30,14 @@ class An_empty_stack {
         void throws_when_queried_for_its_top_item() {
             thenExceptionOfType
                 (IllegalStateException.class)
-                .isThrownBy(() -> { (new Stack<>()).top(); });
+                .isThrownBy(() -> (new Stack<>()).top());
         }
 
         @Test
         void throws_when_popped() {
             thenExceptionOfType
                 (IllegalStateException.class)
-                .isThrownBy(() -> { (new Stack<>()).pop(); });
+                .isThrownBy(() -> (new Stack<>()).pop());
         }
 
         @Test