unused parameter: correctly ignore parameters used in overridden methods

when graph was build over not project scope (IDEA-180281)

java/java-impl/src/com/intellij/codeInspection/deadCode/UnusedDeclarationPresentation.java

@@ -41,7 +41,6 @@ import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.VirtualFileManager;
 import com.intellij.profile.codeInspection.ui.SingleInspectionProfilePanel;
 import com.intellij.psi.*;
-import com.intellij.psi.util.PropertyUtil;
 import com.intellij.psi.util.PropertyUtilBase;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.refactoring.safeDelete.SafeDeleteHandler;
@@ -564,7 +563,15 @@ public class UnusedDeclarationPresentation extends DefaultInspectionToolPresenta
         final PsiElement psiElement = ReadAction.compute(() -> ((RefElement)refEntity).getElement());
         List<CommonProblemDescriptor> foreignDescriptors = new ArrayList<>();
         for (CommonProblemDescriptor descriptor : descriptors) {
-          if (descriptor instanceof ProblemDescriptor && ReadAction.compute(() -> ((ProblemDescriptor)descriptor).getPsiElement()) == psiElement) continue;
+          if (descriptor instanceof ProblemDescriptor) {
+            PsiElement problemElement = ReadAction.compute(() -> {
+              PsiElement element = ((ProblemDescriptor)descriptor).getPsiElement();
+              if (element instanceof PsiIdentifier) element = element.getParent();
+              return element;
+            });
+            if (problemElement == psiElement ||
+                problemElement instanceof PsiParameter && ((PsiParameter)problemElement).getDeclarationScope() == psiElement) continue;
+          }
           foreignDescriptors.add(descriptor);
         }
         if (foreignDescriptors.size() == descriptors.length) return;

java/java-impl/src/com/intellij/codeInspection/deadCode/UnusedParametersInspection.java

@@ -117,7 +117,7 @@ class UnusedParametersInspection extends GlobalJavaBatchInspectionTool {
                   for (int i = 0; i < derived.length && !found[0]; i++) {
                     if (scope == null || !scope.contains(derived[i])) {
                       final PsiParameter[] parameters = derived[i].getParameterList().getParameters();
-                      if (parameters.length >= idx) continue;
+                      if (parameters.length < idx) continue;
                       PsiParameter psiParameter = parameters[idx];
                       ReferencesSearch.search(psiParameter, helper.getUseScope(psiParameter), false)
                         .forEach(new PsiReferenceProcessorAdapter(
@@ -125,7 +125,7 @@ class UnusedParametersInspection extends GlobalJavaBatchInspectionTool {
                             @Override
                             public boolean execute(PsiReference element) {
                               refParameter.parameterReferenced(false);
-                              processor.ignoreElement(refParameter);
+                              processor.ignoreElement(refMethod);
                               found[0] = true;
                               return false;
                             }

java/java-tests/testData/inspection/deadCode/parameterUsedInOutOfScopeOverrider/expected.xml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problems/>

java/java-tests/testData/inspection/deadCode/parameterUsedInOutOfScopeOverrider/src/Test.java

@@ -0,0 +1,7 @@
+public class Test {
+  public void doSmth(String str) {}
+
+  public static void main(String[] args) {
+    new Test().doSmth("");
+  }
+}

java/java-tests/testData/inspection/deadCode/parameterUsedInOutOfScopeOverrider/test_src/Main.java

@@ -0,0 +1,5 @@
+public class Main extends Test {
+  public void doSmth(String str) {
+    System.out.println(str);
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/UnusedDeclarationInSubScopeTest.java

@@ -0,0 +1,39 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.java.codeInspection;
+
+import com.intellij.analysis.AnalysisScope;
+import com.intellij.openapi.roots.ModuleRootManager;
+import com.intellij.openapi.vfs.LocalFileSystem;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.psi.PsiManager;
+import com.intellij.testFramework.PsiTestUtil;
+import org.jetbrains.annotations.NotNull;
+
+public class UnusedDeclarationInSubScopeTest extends AbstractUnusedDeclarationTest {
+  @Override
+  protected void setupRootModel(@NotNull String testDir, @NotNull VirtualFile[] sourceDir, String jdkName) {
+    super.setupRootModel(testDir, sourceDir, jdkName);
+    VirtualFile projectDir = LocalFileSystem.getInstance().findFileByPath(testDir);
+    assertNotNull(projectDir);
+    VirtualFile test = projectDir.findChild("test_src");
+    if (test != null) PsiTestUtil.addSourceRoot(myModule, test, true);
+  }
+
+  @NotNull
+  @Override
+  protected AnalysisScope createAnalysisScope(VirtualFile sourceDir) {
+    VirtualFile[] roots = ModuleRootManager.getInstance(myModule).getSourceRoots(false);
+    assertTrue(roots.length == 1);
+    PsiManager psiManager = PsiManager.getInstance(myProject);
+    return new AnalysisScope(psiManager.findDirectory(roots[0]));
+  }
+
+  public void testParameterUsedInOutOfScopeOverrider() {
+    doTest();
+  }
+
+  @Override
+  protected void doTest() {
+    doTest("deadCode/" + getTestName(true), myToolWrapper);
+  }
+}