SONARJAVA-5099 Fix FP on S1144 if @MethodSource is used without argum…

…ents (#4867)

its/autoscan/src/test/java/org/sonar/java/it/AutoScanTest.java

@@ -198,7 +198,7 @@ public void javaCheckTestSources() throws Exception {
     SoftAssertions softly = new SoftAssertions();
     softly.assertThat(newDiffs).containsExactlyInAnyOrderElementsOf(knownDiffs.values());
     softly.assertThat(newTotal).isEqualTo(knownTotal);
-    softly.assertThat(rulesCausingFPs).hasSize(9);
+    softly.assertThat(rulesCausingFPs).hasSize(10);
     softly.assertThat(rulesNotReporting).hasSize(10);
 
     /**

its/autoscan/src/test/resources/autoscan/diffs/diff_S1144.json

@@ -2,5 +2,5 @@
   "ruleKey": "S1144",
   "hasTruePositives": true,
   "falseNegatives": 1,
-  "falsePositives": 0
-}
+  "falsePositives": 1
+}

java-checks-test-sources/default/src/main/java/checks/UnusedPrivateMethod.java

@@ -1,5 +1,7 @@
 package checks;
 
+import org.junit.jupiter.params.provider.MethodSource;
+
 import java.io.Serializable;
 import java.math.BigDecimal;
 import java.util.ArrayList;
@@ -11,12 +13,25 @@
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
+import java.util.stream.Stream;
 
 import static java.util.Collections.emptySet;
 @interface Observes {}
 
 class UnusedPrivateMethodCheck {
 
+  @MethodSource
+  private void unusedMethodWithWrongAnnotation(){} // Compilant - FN
+
+  @MethodSource()
+  void testMessages(String message) {
+    // ...
+  }
+
+  private static Stream<String> testMessages() { // Compliant, used by @MethodSource
+    return Stream.of("Hello world!", "Carpe diem!");
+  }
+
   private void init(@Observes Object object, String test) {} // Noncompliant
   private void init(@javax.enterprise.event.Observes Object object) {} //Compliant, javax.enterprise.event.Observes is an exception to the rule
   private void jakartaInit(@jakarta.enterprise.event.Observes Object object) {} //Compliant, jakarta.enterprise.event.Observes is an exception to the rule

java-checks/src/main/java/org/sonar/java/checks/unused/UnusedPrivateMethodCheck.java

@@ -82,7 +82,9 @@ private static Stream<MethodTree> findUnusedPrivateMethods(ClassTree tree) {
     methodNames.removeAll(collector.unresolvedMethodNames);
     var filter = new MethodsUsedInAnnotationsFilter(methodNames);
     tree.accept(filter);
-    return unusedPrivateMethods.stream().filter(it -> filter.filteredNames.contains(it.simpleName().name()));
+    var methodTreeStream = unusedPrivateMethods.stream().filter(it -> filter.filteredNames.contains(it.simpleName().name()));
+    var methodSourceAnnotatedMethods = getMethodSourcesNames(tree);
+    return methodTreeStream.filter(it -> !methodSourceAnnotatedMethods.contains(it.simpleName().name()));
   }
 
   private void reportUnusedPrivateMethods(Stream<MethodTree> methods) {
@@ -101,6 +103,19 @@ private void reportUnusedPrivateMethods(Stream<MethodTree> methods) {
       });
   }
 
+  private static List<String> getMethodSourcesNames(ClassTree tree) {
+    return tree.members().stream()
+      .filter(it -> it instanceof MethodTree mt && isAnnotatedWithMethodSource(mt))
+      .map(MethodTree.class::cast)
+      .map(it -> it.simpleName().name())
+      .toList();
+  }
+
+  private static boolean isAnnotatedWithMethodSource(MethodTree methodTree) {
+    return methodTree.modifiers().annotations().stream()
+      .anyMatch(annotation -> annotation.annotationType().symbolType().is("org.junit.jupiter.params.provider.MethodSource"));
+  }
+
   private static class UnusedMethodCollector extends BaseTreeVisitor {
 
     public final List<MethodTree> unusedPrivateMethods = new ArrayList<>();