don't infer annotations in anonymous classes unless they'll be useful

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/ContractInference.java

@@ -17,17 +17,12 @@ package com.intellij.codeInspection.dataFlow;
 
 import com.intellij.codeInsight.NullableNotNullManager;
 import com.intellij.codeInspection.dataFlow.MethodContract.ValueConstraint;
-import com.intellij.openapi.roots.FileIndexFacade;
 import com.intellij.openapi.util.Computable;
 import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.RecursionManager;
-import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.*;
 import com.intellij.psi.tree.IElementType;
-import com.intellij.psi.util.CachedValueProvider;
-import com.intellij.psi.util.CachedValuesManager;
-import com.intellij.psi.util.PsiModificationTracker;
-import com.intellij.psi.util.PsiUtilCore;
+import com.intellij.psi.util.*;
 import com.intellij.util.Function;
 import com.intellij.util.NullableFunction;
 import com.intellij.util.containers.ContainerUtil;
@@ -47,10 +42,10 @@ public class ContractInference {
 
   @NotNull
   public static List<MethodContract> inferContracts(@NotNull final PsiMethod method) {
-    if (isLibraryCode(method)) {
+    if (!InferenceFromSourceUtil.shouldInferFromSource(method)) {
       return Collections.emptyList();
     }
-
+    
     return CachedValuesManager.getCachedValue(method, new CachedValueProvider<List<MethodContract>>() {
       @Nullable
       @Override
@@ -66,12 +61,6 @@ public class ContractInference {
       }
     });
   }
-
-  static boolean isLibraryCode(@NotNull PsiMethod method) {
-    if (method instanceof PsiCompiledElement) return true;
-    VirtualFile virtualFile = PsiUtilCore.getVirtualFile(method);
-    return virtualFile != null && FileIndexFacade.getInstance(method.getProject()).isInLibrarySource(virtualFile);
-  }
 }
 
 class ContractInferenceInterpreter {

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/InferenceFromSourceUtil.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2000-2014 JetBrains s.r.o.
+ *
+ * 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
+ *
+ * http://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 com.intellij.codeInspection.dataFlow;
+
+import com.intellij.openapi.roots.FileIndexFacade;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.psi.*;
+import com.intellij.psi.search.LocalSearchScope;
+import com.intellij.psi.search.searches.MethodReferencesSearch;
+import com.intellij.psi.util.PsiUtil;
+import com.intellij.psi.util.PsiUtilCore;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author peter
+ */
+public class InferenceFromSourceUtil {
+  static boolean shouldInferFromSource(@NotNull PsiMethod method) {
+    if (isLibraryCode(method) ||
+        method.hasModifierProperty(PsiModifier.ABSTRACT) ||
+        PsiUtil.canBeOverriden(method) ||
+        method.getBody() == null) {
+      return false;
+    }
+    
+    if (method.hasModifierProperty(PsiModifier.STATIC)) return true;
+
+    return !isUnusedInAnonymousClass(method);
+  }
+
+  private static boolean isUnusedInAnonymousClass(@NotNull PsiMethod method) {
+    PsiClass containingClass = method.getContainingClass();
+    return containingClass instanceof PsiAnonymousClass &&
+           MethodReferencesSearch.search(method, new LocalSearchScope(containingClass), false).findFirst() == null;
+  }
+
+  private static boolean isLibraryCode(@NotNull PsiMethod method) {
+    if (method instanceof PsiCompiledElement) return true;
+    VirtualFile virtualFile = PsiUtilCore.getVirtualFile(method);
+    return virtualFile != null && FileIndexFacade.getInstance(method.getProject()).isInLibrarySource(virtualFile);
+  }
+}

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/NullityInference.java

@@ -35,7 +35,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 public class NullityInference {
 
   public static Nullness inferNullity(final PsiMethod method) {
-    if (ContractInference.isLibraryCode(method)) {
+    if (!InferenceFromSourceUtil.shouldInferFromSource(method)) {
       return Nullness.UNKNOWN;
     }
 

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/PurityInference.java

@@ -34,7 +34,10 @@ import java.util.List;
 public class PurityInference {
 
   public static boolean inferPurity(@NotNull final PsiMethod method) {
-    if (ContractInference.isLibraryCode(method) || method.getReturnType() == PsiType.VOID || method.getBody() == null || method.isConstructor()) {
+    if (!InferenceFromSourceUtil.shouldInferFromSource(method) ||
+        method.getReturnType() == PsiType.VOID ||
+        method.getBody() == null ||
+        method.isConstructor()) {
       return false;
     }
 

java/java-tests/testSrc/com/intellij/codeInspection/ContractInferenceFromSourceTest.groovy

@@ -16,6 +16,8 @@
 package com.intellij.codeInspection
 
 import com.intellij.codeInspection.dataFlow.ContractInference
+import com.intellij.psi.PsiAnonymousClass
+import com.intellij.psi.util.PsiTreeUtil
 import com.intellij.testFramework.fixtures.LightCodeInsightFixtureTestCase
 
 /**
@@ -448,6 +450,27 @@ public static boolean isBlank(String s) {
     assert c == ['null -> true']
   }
 
+  public void "test no inference for unused anonymous class methods where annotations won't be used anyway"() {
+    def method = PsiTreeUtil.findChildOfType(myFixture.addClass("""
+class Foo {{
+  new Object() {
+    Object foo() { return null;}
+  };
+}}"""), PsiAnonymousClass).methods[0]
+    assert ContractInference.inferContracts(method).collect { it as String } == []
+  }
+
+  public void "test inference for used anonymous class methods"() {
+    def method = PsiTreeUtil.findChildOfType(myFixture.addClass("""
+class Foo {{
+  new Object() {
+    Object foo() { return null;}
+    Object bar() { return foo();}
+  };
+}}"""), PsiAnonymousClass).methods[0]
+    assert ContractInference.inferContracts(method).collect { it as String } == [' -> null']
+  }
+
   private String inferContract(String method) {
     return assertOneElement(inferContracts(method))
   }