From 2efae9fe9aa7de902b3325aa3077f7bc3fc5c62a Mon Sep 17 00:00:00 2001
From: Bas Leijdekkers <basleijdekkers@gmail.com>
Date: Tue, 12 Sep 2017 19:06:24 +0200
Subject: [PATCH] add necessary parentheses when simplifying if (IDEA-178828)

---
 .../src/com/siyeh/ig/psiutils/BoolUtils.java  | 14 ++++-----
 .../trivialIf/Parentheses.after.java          |  5 ++++
 .../controlflow/trivialIf/Parentheses.java    |  6 ++++
 .../fixes/controlflow/TrivialIfFixTest.java   | 30 +++++--------------
 4 files changed, 25 insertions(+), 30 deletions(-)
 create mode 100644 plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.after.java
 create mode 100644 plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.java

diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/BoolUtils.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/BoolUtils.java
index 4605e5ede4a7..774de7c48330 100644
--- a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/BoolUtils.java
+++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/BoolUtils.java
@@ -92,7 +92,7 @@ public class BoolUtils {
     }
     if (expression instanceof PsiPolyadicExpression) {
       final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression)expression;
-      IElementType tokenType = polyadicExpression.getOperationTokenType();
+      final IElementType tokenType = polyadicExpression.getOperationTokenType();
       final PsiExpression[] operands = polyadicExpression.getOperands();
       if (ComparisonUtils.isComparison(polyadicExpression)) {
         final String negatedComparison = ComparisonUtils.getNegatedComparison(tokenType);
@@ -121,23 +121,23 @@ public class BoolUtils {
       }
       if(tokenType.equals(JavaTokenType.ANDAND) || tokenType.equals(JavaTokenType.OROR)) {
         final String targetToken;
-        final boolean needParenthesis;
+        final int newPrecedence;
         if (tokenType.equals(JavaTokenType.ANDAND)) {
           targetToken = "||";
-          needParenthesis = ParenthesesUtils.OR_PRECEDENCE > precedence;
+          newPrecedence = ParenthesesUtils.OR_PRECEDENCE;
         }
         else {
           targetToken = "&&";
-          needParenthesis = ParenthesesUtils.AND_PRECEDENCE > precedence;
+          newPrecedence = ParenthesesUtils.AND_PRECEDENCE;
         }
-        Function<PsiElement, String> replacer = child -> {
+        final Function<PsiElement, String> replacer = child -> {
           if (child instanceof PsiExpression) {
-            return getNegatedExpressionText((PsiExpression)child);
+            return getNegatedExpressionText((PsiExpression)child, newPrecedence);
           }
           return child instanceof PsiJavaToken ? targetToken : child.getText();
         };
         final String join = StringUtil.join(polyadicExpression.getChildren(), replacer, "");
-        return needParenthesis ? '(' + join + ')' : join;
+        return (newPrecedence > precedence) ? '(' + join + ')' : join;
       }
     }
     return '!' + ParenthesesUtils.getText(expression, ParenthesesUtils.PREFIX_PRECEDENCE);
diff --git a/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.after.java b/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.after.java
new file mode 100644
index 000000000000..03f551cdf0cb
--- /dev/null
+++ b/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.after.java
@@ -0,0 +1,5 @@
+class X {
+  boolean test(String s1, String s2) {
+      return (s1 == null || s1.isEmpty()) && (s2 == null || s2.isEmpty());
+  }
+}
\ No newline at end of file
diff --git a/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.java b/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.java
new file mode 100644
index 000000000000..a6a25a053930
--- /dev/null
+++ b/plugins/InspectionGadgets/test/com/siyeh/igfixes/controlflow/trivialIf/Parentheses.java
@@ -0,0 +1,6 @@
+class X {
+  boolean test(String s1, String s2) {
+    if<caret>(s1 != null && !s1.isEmpty() || s2 != null && !s2.isEmpty()) return false;
+    return true;
+  }
+}
\ No newline at end of file
diff --git a/plugins/InspectionGadgets/testsrc/com/siyeh/ig/fixes/controlflow/TrivialIfFixTest.java b/plugins/InspectionGadgets/testsrc/com/siyeh/ig/fixes/controlflow/TrivialIfFixTest.java
index 429c09a8ab11..14fac6e77367 100644
--- a/plugins/InspectionGadgets/testsrc/com/siyeh/ig/fixes/controlflow/TrivialIfFixTest.java
+++ b/plugins/InspectionGadgets/testsrc/com/siyeh/ig/fixes/controlflow/TrivialIfFixTest.java
@@ -28,27 +28,11 @@ public class TrivialIfFixTest extends IGQuickFixesTestCase {
     myDefaultHint = "Simplify 'if else'";
   }
 
-  public void testComments() {
-    doTest();
-  }
-
-  public void testCommentsInAssignment() {
-    doTest();
-  }
-
-  public void testNegatedConditional() {
-    doTest();
-  }
-
-  public void testNegatedConditional1() {
-    doTest();
-  }
-
-  public void testAssert1() {
-    doTest();
-  }
-
-  public void testAssert2() {
-    doTest();
-  }
+  public void testComments() { doTest(); }
+  public void testCommentsInAssignment() { doTest(); }
+  public void testNegatedConditional() { doTest(); }
+  public void testNegatedConditional1() { doTest(); }
+  public void testAssert1() { doTest(); }
+  public void testAssert2() { doTest(); }
+  public void testParentheses() { doTest(); }
 }
\ No newline at end of file