unused declarations: don't search for usages under ReadLock(IDEA-175710)

when jvm-like langs are processed, refs should be already in graph, otherwise they will be caught by post processing task

java/java-analysis-impl/src/com/intellij/codeInspection/deadCode/UnusedDeclarationInspectionBase.java

@@ -43,7 +43,6 @@ import com.intellij.psi.search.DelegatingGlobalSearchScope;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.psi.search.PsiNonJavaFileReferenceProcessor;
 import com.intellij.psi.search.PsiSearchHelper;
-import com.intellij.psi.search.searches.ReferencesSearch;
 import com.intellij.psi.util.PsiMethodUtil;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.containers.HashMap;
@@ -333,16 +332,13 @@ public class UnusedDeclarationInspectionBase extends GlobalInspectionTool {
                   }
                 };
 
-                if (helper.processUsagesInNonJavaFiles(qualifiedName, processor, globalSearchScope)) {
-                  final PsiReference reference = ReferencesSearch.search(psiClass, globalSearchScope).findFirst();
-                  if (reference != null) {
+                helper.processUsagesInNonJavaFiles(qualifiedName, processor, globalSearchScope);
+
+                //references from java-like are already in graph or
+                //they would be checked during GlobalJavaInspectionContextImpl.performPostRunActivities
+                for (RefElement element : refElement.getInReferences()) {
+                  if (!(element instanceof RefJavaElement)) {
                     getEntryPointsManager(globalContext).addEntryPoint(refElement, false);
-                    for (PsiMethod method : psiClass.getMethods()) {
-                      final RefElement refMethod = refManager.getReference(method);
-                      if (refMethod != null) {
-                        getEntryPointsManager(globalContext).addEntryPoint(refMethod, false);
-                      }
-                    }
                   }
                 }
               }

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

@@ -125,6 +125,7 @@ public class UnusedDeclarationPresentation extends DefaultInspectionToolPresenta
       if (!((RefElementImpl)refElement).hasSuspiciousCallers() || ((RefJavaElementImpl)refElement).isSuspiciousRecursive()) return 1;
 
       for (RefElement element : refElement.getInReferences()) {
+        if (refElement instanceof RefFile) return 1;
         if (((UnusedDeclarationInspectionBase)myTool).isEntryPoint(element)) return 1;
       }
 

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

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problems>  
+</problems>
+

java/java-tests/testData/inspection/deadCode/referenceFromGroovy/src/GroovyUsage.groovy

@@ -0,0 +1,5 @@
+class MyGroovyUsage {
+  static void "to use java"() {
+    new Util().foo()
+  }
+}

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

@@ -0,0 +1,3 @@
+class Util {
+    void foo() { }
+}

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

@@ -198,4 +198,8 @@ public class UnusedDeclarationTest extends AbstractUnusedDeclarationTest {
   public void testReferenceFromReflection() {
     doTest();
   }
+
+  public void testReferenceFromGroovy() {
+    doTest();
+  }
 }