Mock different arguments

Author: mincong-h

mockito/mockito-junit5/pom.xml

@@ -33,6 +33,10 @@
       <artifactId>mockito-junit-jupiter</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.assertj</groupId>
+      <artifactId>assertj-core</artifactId>
+    </dependency>
   </dependencies>
 
 </project>

mockito/mockito-junit5/src/test/java/io/mincongh/mockito/init/ArgumentMatchTest.java

@@ -0,0 +1,38 @@
+package io.mincongh.mockito.init;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.Map;
+import java.util.Optional;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+public class ArgumentMatchTest {
+  static class UserRegistry {
+    private final Map<String, String> users;
+
+    public UserRegistry(Map<String, String> users) {
+      this.users = users;
+    }
+
+    Optional<String> getUser(String userId) {
+      return Optional.ofNullable(users.get(userId));
+    }
+  }
+
+  @Test
+  void getUser() {
+    var registry = mock(UserRegistry.class);
+    when(registry.getUser("user1")).thenReturn(Optional.of("User One"));
+    when(registry.getUser("user2")).thenReturn(Optional.of("User Two"));
+    when(registry.getUser("user3")).thenReturn(Optional.empty());
+
+    assertThat(registry.getUser("user1")).hasValue("User One");
+    assertThat(registry.getUser("user2")).hasValue("User Two");
+    assertThat(registry.getUser("user3")).isEmpty();
+  }
+}