add unit tests for anonymous realm

scm-webapp/src/main/java/sonia/scm/security/AnonymousRealm.java

@@ -2,7 +2,6 @@ package sonia.scm.security;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.inject.Inject;
-import org.apache.shiro.authc.AuthenticationException;
 import org.apache.shiro.authc.AuthenticationInfo;
 import org.apache.shiro.authc.AuthenticationToken;
 import org.apache.shiro.authc.credential.AllowAllCredentialsMatcher;
@@ -12,6 +11,8 @@ import sonia.scm.plugin.Extension;
 
 import javax.inject.Singleton;
 
+import static com.google.common.base.Preconditions.checkArgument;
+
 @Singleton
 @Extension
 public class AnonymousRealm extends AuthenticatingRealm {
@@ -36,7 +37,8 @@ public class AnonymousRealm extends AuthenticatingRealm {
   }
 
   @Override
-  protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authenticationToken) throws AuthenticationException {
+  protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authenticationToken) {
+    checkArgument(authenticationToken instanceof AnonymousToken, "%s is required", AnonymousToken.class);
     return helper.authenticationInfoBuilder(SCMContext.USER_ANONYMOUS).build();
   }
 }

scm-webapp/src/test/java/sonia/scm/security/AnonymousRealmTest.java

@@ -0,0 +1,54 @@
+package sonia.scm.security;
+
+import org.apache.shiro.authc.AuthenticationInfo;
+import org.apache.shiro.authc.UsernamePasswordToken;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import sonia.scm.SCMContext;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class AnonymousRealmTest {
+
+  @Mock
+  private DAORealmHelperFactory realmHelperFactory;
+
+  @Mock
+  private DAORealmHelper realmHelper;
+
+  @Mock
+  private DAORealmHelper.AuthenticationInfoBuilder builder;
+
+  @InjectMocks
+  private AnonymousRealm realm;
+
+  @Mock
+  private AuthenticationInfo authenticationInfo;
+
+  @BeforeEach
+  void prepareObjectUnderTest() {
+    when(realmHelperFactory.create(AnonymousRealm.REALM)).thenReturn(realmHelper);
+    realm = new AnonymousRealm(realmHelperFactory);
+  }
+
+  @Test
+  void shouldDoGetAuthentication() {
+    when(realmHelper.authenticationInfoBuilder(SCMContext.USER_ANONYMOUS)).thenReturn(builder);
+    when(builder.build()).thenReturn(authenticationInfo);
+
+    AuthenticationInfo result = realm.doGetAuthenticationInfo(new AnonymousToken());
+    assertThat(result).isSameAs(authenticationInfo);
+  }
+
+  @Test
+  void shouldThrowIllegalArgumentExceptionForWrongTypeOfToken() {
+    assertThrows(IllegalArgumentException.class, () -> realm.doGetAuthenticationInfo(new UsernamePasswordToken()));
+  }
+}