GH-74 - Bean references in Application Module Canvas now get de-duplicated.

Author: odrotbohm

spring-modulith-core/src/main/java/org/springframework/modulith/model/ApplicationModuleDependencies.java

@@ -17,7 +17,9 @@
 
 import lombok.RequiredArgsConstructor;
 
+import java.util.HashSet;
 import java.util.List;
+import java.util.function.Function;
 import java.util.stream.Stream;
 
 import org.springframework.util.Assert;
@@ -73,6 +75,23 @@ public Stream<ApplicationModuleDependency> stream() {
 		return dependencies.stream();
 	}
 
+	/**
+	 * Return all {@link ApplicationModuleDependency} instances unique by the value extracted using the given
+	 * {@link Function}.
+	 *
+	 * @param extractor will never be {@literal null}.
+	 * @return will never be {@literal null}.
+	 */
+	public Stream<ApplicationModuleDependency> uniqueStream(Function<ApplicationModuleDependency, Object> extractor) {
+
+		Assert.notNull(extractor, "Extractor function must not be null!");
+
+		var seenTargets = new HashSet<>();
+
+		return dependencies.stream()
+				.filter(it -> seenTargets.add(extractor.apply(it)));
+	}
+
 	public ApplicationModuleDependencies withType(DependencyType type) {
 
 		var filtered = dependencies.stream()

spring-modulith-docs/src/main/java/org/springframework/modulith/docs/Asciidoctor.java

@@ -29,6 +29,7 @@
 import org.springframework.modulith.docs.Documenter.CanvasOptions;
 import org.springframework.modulith.docs.Documenter.CanvasOptions.Groupings;
 import org.springframework.modulith.model.ApplicationModule;
+import org.springframework.modulith.model.ApplicationModuleDependency;
 import org.springframework.modulith.model.ApplicationModules;
 import org.springframework.modulith.model.ArchitecturallyEvidentType;
 import org.springframework.modulith.model.DependencyType;
@@ -363,7 +364,8 @@ public String toAsciidoctor(String source) {
 	 */
 	public String renderBeanReferences(ApplicationModule module) {
 
-		var bullets = module.getDependencies(modules, DependencyType.USES_COMPONENT).stream()
+		var bullets = module.getDependencies(modules, DependencyType.USES_COMPONENT)
+				.uniqueStream(ApplicationModuleDependency::getTargetType)
 				.map(it -> "%s (in %s)".formatted(toInlineCode(it.getTargetType()), it.getTargetModule().getDisplayName()))
 				.map(this::toBulletPoint)
 				.collect(Collectors.joining("\n"));