[java] inferred type accessibility (IDEA-293838)

GitOrigin-RevId: 70bcc7dd766648d5b5d9389c1918293101563002

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightMethodUtil.java

@@ -414,6 +414,11 @@ public final class HighlightMethodUtil {
       if (highlightInfo == null) {
         highlightInfo = createIncompatibleTypeHighlightInfo(methodCall, resolveHelper, (MethodCandidateInfo)resolveResult, methodCall);
       }
+      
+      if (highlightInfo == null) {
+        highlightInfo = checkInferredReturnTypeAccessible((MethodCandidateInfo)resolveResult, methodCall);
+      }
+      
     }
     else {
       MethodCandidateInfo candidateInfo = resolveResult instanceof MethodCandidateInfo ? (MethodCandidateInfo)resolveResult : null;
@@ -1846,6 +1851,21 @@ public final class HighlightMethodUtil {
     return null;
   }
 
+  private static HighlightInfo checkInferredReturnTypeAccessible(@NotNull MethodCandidateInfo info, @NotNull PsiMethodCallExpression methodCall) {
+    PsiClass targetClass = PsiUtil.resolveClassInClassTypeOnly(info.getElement().getReturnType());
+    if (targetClass instanceof PsiTypeParameter) {
+      PsiClass inferred = PsiUtil.resolveClassInClassTypeOnly(info.getSubstitutor().substitute((PsiTypeParameter)targetClass));
+      if (inferred != null && !PsiUtil.isAccessible(inferred, methodCall, null)) {
+        return HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
+          .descriptionAndTooltip(JavaErrorBundle.message("inaccessible.type",
+                                                         PsiFormatUtil.formatClass(inferred, PsiFormatUtilBase.SHOW_FQ_NAME | PsiFormatUtilBase.SHOW_NAME)))
+          .range(methodCall.getArgumentList())
+          .create();
+      }
+    }
+    return null;
+  }
+
   private static void registerFixesOnInvalidConstructorCall(@NotNull PsiConstructorCall constructorCall,
                                                             @Nullable PsiJavaCodeReferenceElement classReference,
                                                             @NotNull PsiExpressionList list,

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advFixture/ProtectedInnerClass.java

@@ -0,0 +1,10 @@
+package a.b;
+import a.*;
+public class Foo {
+	private <T> T f() {	return null;}
+	void m(Outer o){
+		o.get(f<error descr="'a.Outer.Inner' is inaccessible here">()</error>);
+    o.get1();
+    o.f = f<error descr="'a.Outer.Inner' is inaccessible here">()</error>;
+	}
+}

java/java-tests/testSrc/com/intellij/java/codeInsight/daemon/LightAdvHighlightingFixtureTest.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.java.codeInsight.daemon;
 
 import com.intellij.JavaTestUtil;
@@ -254,6 +254,19 @@ public class LightAdvHighlightingFixtureTest extends LightJavaCodeInsightFixture
     myFixture.checkResultByFile(getTestName(false) + "_after.java");
   }
 
+  public void testProtectedInnerClass() {
+    myFixture.addClass("package a;\n" +
+                       "public class Outer {\n" +
+                       " public Object get(Inner key) {\n" +
+                       "  return null;\n" +
+                       " }\n" +
+                       " public Inner get1() {return null;} \n" +
+                       " public Inner f; \n" +
+                       " protected class Inner {}\n" +
+                       "}");
+    doTest();
+  }
+
   private void doTest() {
     myFixture.configureByFile(getTestName(false) + ".java");
     myFixture.checkHighlighting();