[java-highlighting] IDEA-340063 Don't offer import from implicitly declared classes

GitOrigin-RevId: 7cda6a2eaa67c0c557ce53f61bfd345d5d773694

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java

@@ -32,6 +32,7 @@ import com.intellij.psi.codeStyle.JavaCodeStyleSettings;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.psi.search.PsiShortNamesCache;
 import com.intellij.psi.util.InheritanceUtil;
+import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.ArrayUtil;
 import com.intellij.util.ThreeState;
@@ -195,7 +196,9 @@ public abstract class ImportClassFixBase<T extends PsiElement, R extends PsiRefe
     JavaPsiFacade facade = JavaPsiFacade.getInstance(project);
     classList.removeIf(aClass -> (anyAccessibleFound ||
                                   !BaseIntentionAction.canModify(aClass) ||
-                                  facade.arePackagesTheSame(aClass, myReferenceElement)) && !isAccessible(aClass, myReferenceElement));
+                                  facade.arePackagesTheSame(aClass, myReferenceElement) ||
+                                  PsiTreeUtil.getParentOfType(aClass, PsiImplicitClass.class) != null) &&
+                                 !isAccessible(aClass, myReferenceElement));
 
     filterByRequiredMemberName(classList);
 

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/PsiResolveHelperImpl.java

@@ -16,6 +16,7 @@ import com.intellij.psi.scope.conflictResolvers.DuplicateConflictResolver;
 import com.intellij.psi.scope.processor.MethodCandidatesProcessor;
 import com.intellij.psi.scope.processor.MethodResolverProcessor;
 import com.intellij.psi.scope.util.PsiScopesUtil;
+import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.util.PsiUtil;
 import com.intellij.util.IncorrectOperationException;
 import com.intellij.util.SmartList;
@@ -130,9 +131,28 @@ public class PsiResolveHelperImpl implements PsiResolveHelper {
     if (accessible && member instanceof PsiClass && !(member instanceof PsiTypeParameter)) {
       accessible = isAccessible(moduleSystem -> moduleSystem.isAccessible(((PsiClass)member), place));
     }
+    if (fromImplicitClass(member, place)) {
+      return false;
+    }
     return accessible;
   }
 
+  /**
+   * Determines whether the given member is from an implicit class or not.
+   * If it is from implicit class, that place is in the same class
+   *
+   * @param member the member to check
+   * @param place  the place where the check is performed
+   * @return true if the member is not from an implicit class or if place and member are both in the same implicit class, false otherwise.
+   */
+  private static boolean fromImplicitClass(@NotNull PsiMember member, @NotNull PsiElement place) {
+    PsiImplicitClass implicitClass = PsiTreeUtil.getParentOfType(member, PsiImplicitClass.class);
+    if (implicitClass == null) {
+      return false;
+    }
+    return !PsiTreeUtil.isAncestor(implicitClass, place, false);
+  }
+
   @Override
   public boolean isAccessible(@NotNull PsiPackage pkg, @NotNull PsiElement place) {
     return isAccessible(moduleSystem -> moduleSystem.isAccessible(pkg.getQualifiedName(), null, place));

java/java-tests/testData/refactoring/replaceConstructorWithFactory/beforeImplicitClass.java

@@ -0,0 +1,5 @@
+
+void main() {
+  Rar x = new R<caret>ar();
+}
+

java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.java

@@ -804,4 +804,24 @@ public class AddImportActionTest extends LightJavaCodeInsightFixtureTestCase {
             final List<?> list = new @AssertTrue ArrayList<Object>();
         }""");
   }
+
+  public void testNotImportFromImplicitClass() {
+    IdeaTestUtil.withLevel(getModule(), LanguageLevel.JDK_21_PREVIEW, ()->{
+      myFixture.addClass("""
+                                             enum E {A, B}
+                                                   
+                                             static class Rar {
+                                             }
+                                                   
+                                             void main() {
+                                             }
+                                             """);
+      myFixture.configureByText("a.java", """
+      void main() {
+          R<caret>ar x = new Rar();
+      }
+            """);
+      assertTrue(myFixture.filterAvailableIntentions("Import class").isEmpty());
+    });
+  }
 }