Polishing.

Add unit tests.

See #3304

src/test/java/org/springframework/data/convert/CustomConversionsUnitTests.java

@@ -273,6 +273,16 @@ class CustomConversionsUnitTests {
 		assertThat(conversionService.canConvert(List.class, io.vavr.collection.List.class)).isTrue();
 	}
 
+	@Test // GH-3304
+	void registersMultipleConvertersCorrectly() {
+
+		CustomConversions customConversions = new CustomConversions(new ConverterConfiguration(StoreConversions.NONE,
+				List.of(PointToMapConverter.INSTANCE, new FormatConverterFactory()), (it) -> true, null));
+
+		assertThat(customConversions.hasCustomWriteTarget(Point.class, Map.class)).isTrue();
+		assertThat(customConversions.hasCustomWriteTarget(String.class, Format.class)).isTrue();
+	}
+
 	@Test // GH-1484
 	void doesNotFailIfPropertiesConversionIsNull() {
 

src/test/java/org/springframework/data/spel/ExtensionAwareEvaluationContextProviderUnitTests.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.spel;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.data.spel.spi.EvaluationContextExtension;
+import org.springframework.expression.spel.support.StandardEvaluationContext;
+
+/**
+ * Unit tests for {@link ExtensionAwareEvaluationContextProvider}.
+ *
+ * @author Mark Paluch
+ */
+class ExtensionAwareEvaluationContextProviderUnitTests {
+
+	@Test // GH-3304
+	void shouldRegisterMultipleProvidersCorrectly() {
+
+		ExtensionAwareEvaluationContextProvider provider = new ExtensionAwareEvaluationContextProvider(
+				List.of(FirstExtension.INSTANCE, SecondExtension.INSTANCE));
+		StandardEvaluationContext evaluationContext = provider.getEvaluationContext(new GenericModelRoot());
+
+		assertThat(evaluationContext).isNotNull();
+	}
+
+	/**
+	 * Extension without exposing a concrete extension type.
+	 */
+	enum FirstExtension implements EvaluationContextExtension {
+
+		INSTANCE;
+
+		@Override
+		public String getExtensionId() {
+			return "generic1";
+		}
+
+		@Override
+		public Object getRootObject() {
+			return new GenericModelRoot();
+		}
+	}
+
+	/**
+	 * Extension without exposing a concrete extension type.
+	 */
+	enum SecondExtension implements EvaluationContextExtension {
+
+		INSTANCE;
+
+		@Override
+		public String getExtensionId() {
+			return "generic2";
+		}
+
+		@Override
+		public Object getRootObject() {
+			return new GenericModelRoot();
+		}
+	}
+
+	record GenericModelRoot() {
+	}
+
+}