From 07a086daced6f2798442b3a8af91d9d52453796c Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Tue, 6 Jun 2017 18:57:02 +0300
Subject: [PATCH] don't suggest inaccessible functional interfaces
 (IDEA-174008)

---
 .../FunctionalInterfaceSuggester.java           |  3 +++
 ...oreNoSuggestionForInaccessibleInterface.java | 17 +++++++++++++++++
 .../IntroduceFunctionalVariableTest.java        | 11 +++++++++++
 3 files changed, 31 insertions(+)
 create mode 100644 java/java-tests/testData/refactoring/introduceFunctionalVariable/beforeNoSuggestionForInaccessibleInterface.java

diff --git a/java/java-impl/src/com/intellij/codeInsight/FunctionalInterfaceSuggester.java b/java/java-impl/src/com/intellij/codeInsight/FunctionalInterfaceSuggester.java
index be15abead8b3..1308058d413a 100644
--- a/java/java-impl/src/com/intellij/codeInsight/FunctionalInterfaceSuggester.java
+++ b/java/java-impl/src/com/intellij/codeInsight/FunctionalInterfaceSuggester.java
@@ -76,6 +76,9 @@ public class FunctionalInterfaceSuggester {
     }
 
     return suggestFunctionalInterfaces(method, aClass -> {
+      if (!JavaPsiFacade.getInstance(method.getProject()).getResolveHelper().isAccessible(aClass, method, null)) {
+        return null;
+      }
       final PsiMethod interfaceMethod = LambdaUtil.getFunctionalInterfaceMethod(aClass);
       if (interfaceMethod != null) {
         final PsiParameter[] parameters = method.getParameterList().getParameters();
diff --git a/java/java-tests/testData/refactoring/introduceFunctionalVariable/beforeNoSuggestionForInaccessibleInterface.java b/java/java-tests/testData/refactoring/introduceFunctionalVariable/beforeNoSuggestionForInaccessibleInterface.java
new file mode 100644
index 000000000000..f9b3cad32a45
--- /dev/null
+++ b/java/java-tests/testData/refactoring/introduceFunctionalVariable/beforeNoSuggestionForInaccessibleInterface.java
@@ -0,0 +1,17 @@
+class A {
+ void assignment(double v, int x, int y) {
+        String result;
+<selection>
+        result = format("digit %f", v, x, y );
+</selection>
+        System.out.println(result);
+    }
+
+}
+
+class B {
+    @FunctionalInterface
+    private interface DII {
+        String doIt(double d, int x, int y);
+    }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/java/refactoring/IntroduceFunctionalVariableTest.java b/java/java-tests/testSrc/com/intellij/java/refactoring/IntroduceFunctionalVariableTest.java
index 21aaaa4c4269..a608f3868816 100644
--- a/java/java-tests/testSrc/com/intellij/java/refactoring/IntroduceFunctionalVariableTest.java
+++ b/java/java-tests/testSrc/com/intellij/java/refactoring/IntroduceFunctionalVariableTest.java
@@ -20,6 +20,7 @@ import com.intellij.pom.java.LanguageLevel;
 import com.intellij.refactoring.extractMethod.ExtractMethodProcessor;
 import com.intellij.refactoring.extractMethod.InputVariables;
 import com.intellij.refactoring.introduceVariable.IntroduceFunctionalVariableHandler;
+import com.intellij.refactoring.util.CommonRefactoringUtil;
 import com.intellij.testFramework.MapDataContext;
 import com.intellij.testFramework.TestDataPath;
 import org.jetbrains.annotations.NotNull;
@@ -62,6 +63,16 @@ public class IntroduceFunctionalVariableTest extends LightRefactoringTestCase  {
     doTest(0);
   }
 
+  public void testNoSuggestionForInaccessibleInterface() throws Exception {
+    try {
+      doTest();
+      fail("Should be shown a error hint");
+    }
+    catch (CommonRefactoringUtil.RefactoringErrorHintException e) {
+      assertEquals("No applicable functional interfaces found", e.getMessage());
+    }
+  }
+
   private void doTest(int... disableParams) {
     boolean enabled = true;
     try {