Add unit test

plume-test/src/test/java/com/coreoz/plume/mocks/MockedClockTest.java

@@ -0,0 +1,91 @@
+package com.coreoz.plume.mocks;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.*;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class MockedClockTest {
+    static final Instant fixedInstant = Instant.parse("2000-01-01T10:00:00Z");
+    static final Clock fixedClock = Clock.fixed(fixedInstant, ZoneId.systemDefault());
+
+    @Test
+    void changeClock__when_newClockProvided__should_useNewClock() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+
+        // Act
+        mockedClock.changeClock(fixedClock);
+
+        // Assert
+        assertThat(mockedClock.instant()).isEqualTo(fixedClock.instant());
+    }
+
+    @Test
+    void executeWithClock__when_functionExecuted__should_useNewClockTemporarily() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+
+        // Act & Assert
+        mockedClock.executeWithClock(fixedClock, () -> {
+            assertThat(mockedClock.instant()).isEqualTo(fixedClock.instant());
+        });
+
+        // Verify clock reverted
+        assertThat(mockedClock.instant()).isNotEqualTo(fixedClock.instant());
+    }
+
+    @Test
+    void executeWithInstant__when_fixedInstantProvided__should_useFixedInstantTemporarily() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+
+        // Act & Assert
+        mockedClock.executeWithInstant(fixedInstant, () -> {
+            assertThat(mockedClock.instant()).isEqualTo(fixedInstant);
+        });
+
+        // Verify clock reverted
+        assertThat(mockedClock.instant()).isNotEqualTo(fixedInstant);
+    }
+
+    @Test
+    void setConstantInstant__when_fixedInstantProvided__should_useFixedInstant() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+
+        // Act
+        mockedClock.setConstantInstant(fixedInstant);
+
+        // Assert
+        assertThat(mockedClock.instant()).isEqualTo(fixedInstant);
+    }
+
+    @Test
+    void executeWithConstantTime__when_functionExecuted__should_useCurrentInstantTemporarily() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+        Instant beforeExecution = Instant.now();
+
+        // Act & Assert
+        mockedClock.executeWithConstantTime(() -> {
+            Instant duringExecution = mockedClock.instant();
+            assertThat(duringExecution).isAfterOrEqualTo(beforeExecution);
+        });
+    }
+
+    @Test
+    void setTickingClockFromInstant__when_instantProvided__should_setOffsetClock() {
+        // Arrange
+        MockedClock mockedClock = new MockedClock();
+        Instant futureInstant = Instant.now().plusSeconds(10);
+
+        // Act
+        mockedClock.setTickingClockFromInstant(futureInstant);
+
+        // Assert
+        Instant now = Instant.now();
+        assertThat(mockedClock.instant()).isBetween(now, futureInstant);
+    }
+}