dfa: introduce ImplicitUsageProvider.isImplicitlyNotNullInitialized to support Mockito (IDEA-167790) in a way that doesn't break lombok (IDEA-170490)

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/value/DfaVariableValue.java

@@ -24,10 +24,11 @@
  */
 package com.intellij.codeInspection.dataFlow.value;
 
-import com.intellij.codeInsight.daemon.impl.UnusedSymbolUtil;
+import com.intellij.codeInsight.daemon.ImplicitUsageProvider;
 import com.intellij.codeInsight.daemon.impl.analysis.JavaGenericsUtil;
 import com.intellij.codeInspection.dataFlow.DfaPsiUtil;
 import com.intellij.codeInspection.dataFlow.Nullness;
+import com.intellij.openapi.extensions.Extensions;
 import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.util.Trinity;
 import com.intellij.patterns.ElementPattern;
@@ -38,6 +39,7 @@ import com.intellij.psi.search.SearchScope;
 import com.intellij.psi.search.searches.ReferencesSearch;
 import com.intellij.psi.util.*;
 import com.intellij.util.SmartList;
+import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.containers.MultiMap;
 import com.siyeh.ig.psiutils.MethodUtils;
 import org.jetbrains.annotations.NotNull;
@@ -229,10 +231,14 @@ public class DfaVariableValue extends DfaValue {
 
   private static boolean isOnlyImplicitlyInitialized(PsiField field) {
     return CachedValuesManager.getCachedValue(field, () -> CachedValueProvider.Result.create(
-      UnusedSymbolUtil.isImplicitWrite(field.getProject(), field, null) && weAreSureThereAreNoExplicitWrites(field),
+      isImplicitlyInitializedNotNull(field) && weAreSureThereAreNoExplicitWrites(field),
       PsiModificationTracker.MODIFICATION_COUNT));
   }
 
+  private static boolean isImplicitlyInitializedNotNull(PsiField field) {
+    return ContainerUtil.exists(Extensions.getExtensions(ImplicitUsageProvider.EP_NAME), p -> p.isImplicitlyNotNullInitialized(field));
+  }
+
   private static boolean weAreSureThereAreNoExplicitWrites(PsiField field) {
     String name = field.getName();
     if (name == null || field.getInitializer() != null) return false;

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

@@ -446,6 +446,11 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
 
       @Override
       public boolean isImplicitWrite(PsiElement element) {
+        return false;
+      }
+
+      @Override
+      public boolean isImplicitlyNotNullInitialized(@NotNull PsiElement element) {
         return element instanceof PsiField && ((PsiField)element).getName().startsWith("field");
       }
     }, myFixture.getTestRootDisposable());

platform/analysis-api/src/com/intellij/codeInsight/daemon/ImplicitUsageProvider.java

@@ -18,6 +18,7 @@ package com.intellij.codeInsight.daemon;
 
 import com.intellij.openapi.extensions.ExtensionPointName;
 import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Allows to disable highlighting of certain elements as unused when such elements are not referenced
@@ -36,4 +37,11 @@ public interface ImplicitUsageProvider {
   boolean isImplicitUsage(PsiElement element);
   boolean isImplicitRead(PsiElement element);
   boolean isImplicitWrite(PsiElement element);
+
+  /**
+   * @return true if the given element is implicitly initialized to a non-null value
+   */
+  default boolean isImplicitlyNotNullInitialized(@NotNull PsiElement element) {
+    return false;
+  }
 }

plugins/junit/src/com/intellij/execution/junit2/inspection/JUnitImplicitUsageProvider.java

@@ -20,6 +20,7 @@ import com.intellij.codeInsight.daemon.ImplicitUsageProvider;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiField;
 import com.intellij.psi.PsiParameter;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.Arrays;
 import java.util.List;
@@ -50,4 +51,9 @@ public class JUnitImplicitUsageProvider implements ImplicitUsageProvider {
     }
     return element instanceof PsiField && AnnotationUtil.isAnnotated((PsiField) element, INJECTED_FIELD_ANNOTATIONS);
   }
+
+  @Override
+  public boolean isImplicitlyNotNullInitialized(@NotNull PsiElement element) {
+    return isImplicitWrite(element);
+  }
 }

plugins/ui-designer/src/com/intellij/uiDesigner/binding/UIDesignerImplicitUsageProvider.java

@@ -21,6 +21,7 @@ import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiField;
 import com.intellij.psi.PsiMethod;
 import com.intellij.uiDesigner.compiler.AsmCodeGenerator;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author yole
@@ -45,4 +46,9 @@ public class UIDesignerImplicitUsageProvider implements ImplicitUsageProvider {
   public boolean isImplicitWrite(PsiElement element) {
     return element instanceof PsiField && FormReferenceProvider.getFormFile((PsiField)element) != null;
   }
+
+  @Override
+  public boolean isImplicitlyNotNullInitialized(@NotNull PsiElement element) {
+    return isImplicitWrite(element);
+  }
 }