From c69fc7d594eb360c1778c4bcad6efdce0f4a42f6 Mon Sep 17 00:00:00 2001
From: Tagir Valeev <Tagir.Valeev@jetbrains.com>
Date: Fri, 6 Jul 2018 12:43:08 +0700
Subject: [PATCH] LengthOneStringInConcatenationInspection: support parentheses

---
 .../LengthOneStringsInConcatenationInspection.java         | 3 ++-
 .../LengthOneStringInConcatenationInspection.java          | 1 +
 .../length_one_strings_in_concatenation/expected.xml       | 7 +++++++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/performance/LengthOneStringsInConcatenationInspection.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/performance/LengthOneStringsInConcatenationInspection.java
index 7023c85df437..d51f2e1edfe0 100644
--- a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/performance/LengthOneStringsInConcatenationInspection.java
+++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/performance/LengthOneStringsInConcatenationInspection.java
@@ -19,6 +19,7 @@ import com.intellij.codeInspection.ProblemDescriptor;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.*;
+import com.intellij.psi.util.PsiUtil;
 import com.siyeh.InspectionGadgetsBundle;
 import com.siyeh.ig.BaseInspection;
 import com.siyeh.ig.BaseInspectionVisitor;
@@ -118,7 +119,7 @@ public class LengthOneStringsInConcatenationInspection
     }
 
     static boolean isArgumentOfStringAppend(PsiExpression expression) {
-      final PsiElement parent = expression.getParent();
+      final PsiElement parent = PsiUtil.skipParenthesizedExprUp(expression.getParent());
       if (parent == null) {
         return false;
       }
diff --git a/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/LengthOneStringInConcatenationInspection.java b/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/LengthOneStringInConcatenationInspection.java
index c2644df1f70f..80195c182b2b 100644
--- a/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/LengthOneStringInConcatenationInspection.java
+++ b/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/LengthOneStringInConcatenationInspection.java
@@ -23,5 +23,6 @@ public class LengthOneStringInConcatenationInspection
         System.out.println(1 + "b" + "asdf");
         System.out.println("a" + );
         System.out.println("asdf" + ("b") + 2);
+        buffer2.append(("p"));
     }
 }
\ No newline at end of file
diff --git a/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/expected.xml b/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/expected.xml
index 92cd772b9312..031e42c74222 100644
--- a/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/expected.xml
+++ b/plugins/InspectionGadgets/test/com/siyeh/igtest/performance/length_one_strings_in_concatenation/expected.xml
@@ -55,4 +55,11 @@
     <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Single character string concatenation</problem_class>
     <description>&lt;code&gt;&quot;b&quot;&lt;/code&gt; can be replaced with 'b' #loc</description>
   </problem>
+
+  <problem>
+    <file>LengthOneStringInConcatenationInspection.java</file>
+    <line>26</line>
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Single character string concatenation</problem_class>
+    <description>&lt;code&gt;&quot;p&quot;&lt;/code&gt; can be replaced with 'p' #loc</description>
+  </problem>
 </problems>
\ No newline at end of file