From 82f213c6ab8d8c94eb7599fdcb81e96cc000261e Mon Sep 17 00:00:00 2001
From: Bas Leijdekkers <basleijdekkers@gmail.com>
Date: Thu, 11 Oct 2018 16:49:34 +0200
Subject: [PATCH] IG: fix NPE on invalid code (IDEA-200213)

---
 .../siyeh/ig/style/UnnecessaryParenthesesInspection.java    | 6 ++++--
 .../UnnecessaryParenthesesInspection.java                   | 6 ++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/style/UnnecessaryParenthesesInspection.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/style/UnnecessaryParenthesesInspection.java
index 4bdc6f7238cd..956687f2a083 100644
--- a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/style/UnnecessaryParenthesesInspection.java
+++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/style/UnnecessaryParenthesesInspection.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2012 Dave Griffith, Bas Leijdekkers
+ * Copyright 2003-2018 Dave Griffith, Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,6 +25,7 @@ import com.siyeh.ig.BaseInspection;
 import com.siyeh.ig.BaseInspectionVisitor;
 import com.siyeh.ig.InspectionGadgetsFix;
 import com.siyeh.ig.psiutils.ParenthesesUtils;
+import com.siyeh.ipp.psiutils.ErrorUtil;
 import org.jetbrains.annotations.NotNull;
 
 import javax.swing.*;
@@ -120,7 +121,8 @@ public class UnnecessaryParenthesesInspection extends BaseInspection implements
           return;
         }
       }
-      if (!ParenthesesUtils.areParenthesesNeeded(expression, ignoreClarifyingParentheses)) {
+      if (!ParenthesesUtils.areParenthesesNeeded(expression, ignoreClarifyingParentheses) &&
+          !ErrorUtil.containsError(expression) && !ErrorUtil.containsError(expression.getExpression())) {
         registerError(expression);
         return;
       }
diff --git a/plugins/InspectionGadgets/test/com/siyeh/igtest/style/unnecessary_parentheses/UnnecessaryParenthesesInspection.java b/plugins/InspectionGadgets/test/com/siyeh/igtest/style/unnecessary_parentheses/UnnecessaryParenthesesInspection.java
index dd63ad8bc997..f88e28e1b184 100644
--- a/plugins/InspectionGadgets/test/com/siyeh/igtest/style/unnecessary_parentheses/UnnecessaryParenthesesInspection.java
+++ b/plugins/InspectionGadgets/test/com/siyeh/igtest/style/unnecessary_parentheses/UnnecessaryParenthesesInspection.java
@@ -129,3 +129,9 @@ public class UnnecessaryParenthesesInspection
     return <error descr="Incompatible types. Found: 'int', required: '<lambda expression>'">(a -> a)=1</error>;
   }
 }
+class A{
+
+  A() {
+    ((<error descr="Expression expected"><</error><error descr="Cannot resolve symbol 'x'">x</error>><error descr="Expression expected">)</error><EOLError descr="';' expected"></EOLError>
+  }
+}