IDEA-182933 Simplifying boolean condition removes necessary brackets and changes semantics

java/java-tests/testData/inspection/dataFlow/fixture/SimplifyConcatWithParentheses.java

@@ -0,0 +1,13 @@
+class Test {
+
+  // IDEA-182933
+  public static void main(String[] args) {
+    int a = 1;
+    int b = 2;
+    boolean f = false;
+
+    String s = "Hello " + (a + b) + (<warning descr="Condition 'f' is always 'false'"><caret>f</warning> ? " Earth" : " World");
+
+    System.out.println(s); // Prints Hello 3 World
+  }
+}

java/java-tests/testData/inspection/dataFlow/fixture/SimplifyConcatWithParentheses_after.java

@@ -0,0 +1,13 @@
+class Test {
+
+  // IDEA-182933
+  public static void main(String[] args) {
+    int a = 1;
+    int b = 2;
+    boolean f = false;
+
+    String s = "Hello " + (a + b) + " World";
+
+    System.out.println(s); // Prints Hello 3 World
+  }
+}

java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java

@@ -498,6 +498,11 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
     checkIntentionResult("Simplify 'Test.valueOf(value) != null' to true extracting side effects");
   }
 
+  public void testSimplifyConcatWithParentheses() {
+    doTest();
+    checkIntentionResult("Simplify 'f' to false");
+  }
+
   public void testSideEffectWhile() {
     doTest();
     checkIntentionResult("Remove 'while' statement extracting side effects");

plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/psiutils/ParenthesesUtils.java

@@ -309,7 +309,8 @@ public class ParenthesesUtils {
             return;
           }
         }
-        if (ignoreClarifyingParentheses) {
+        if (ignoreClarifyingParentheses ||
+            (parentOperator == JavaTokenType.PLUS && TypeUtils.isJavaLangString(parentType) && !TypeUtils.isJavaLangString(bodyType))) {
           if (parentOperator.equals(bodyOperator)) {
             removeParentheses(body, ignoreClarifyingParentheses);
           }