Add parentheses around replacements in UnnecessaryStringBuilder when necessary.

PiperOrigin-RevId: 871769997

Author: graememorgan

core/src/main/java/com/google/errorprone/bugpatterns/UnnecessaryStringBuilder.java

@@ -108,9 +108,14 @@ public Description matchNewClass(NewClassTree tree, VisitorState state) {
         parts.add(getOnlyElement(methodInvocationTree.getArguments()));
         path = parentPath.getParentPath();
       } else if (TO_STRING.matches(methodInvocationTree, state)) {
+        String replacement = replacement(state, parts);
+        Tree parent = grandParent.getParentPath().getLeaf();
+        if (parent instanceof MemberSelectTree memberSelectTree
+            && memberSelectTree.getExpression().equals(methodInvocationTree)) {
+          replacement = "(" + replacement + ")";
+        }
         return describeMatch(
-            methodInvocationTree,
-            SuggestedFix.replace(methodInvocationTree, replacement(state, parts)));
+            methodInvocationTree, SuggestedFix.replace(methodInvocationTree, replacement));
       } else {
         // another instance method on StringBuilder
         return NO_MATCH;

core/src/test/java/com/google/errorprone/bugpatterns/UnnecessaryStringBuilderTest.java

@@ -16,8 +16,6 @@
 
 package com.google.errorprone.bugpatterns;
 
-import static com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode.TEXT_MATCH;
-
 import com.google.errorprone.BugCheckerRefactoringTestHelper;
 import com.google.errorprone.CompilationTestHelper;
 import org.junit.Test;
@@ -204,7 +202,6 @@ void f() {
         .doTest();
   }
 
-  // TODO: b/472686687 - the refactoring should add parens
   @Test
   public void needsEnclosingParens() {
     refactoringHelper
@@ -222,15 +219,10 @@ void f(String hello) {
             """
             abstract class Test {
               void f(String hello) {
-                hello + 1.getBytes();
+                (hello + 1).getBytes();
               }
             }
             """)
-        // TODO: b/472686687 - remove allowBreakingChanges when the bug is fixed
-        .allowBreakingChanges()
-        // TODO: b/472686687 - remove allowFormattingErrors when the bug is fixed
-        .allowFormattingErrors()
-        // TODO: b/472686687 - remove TEXT_MATCH when the bug is fixed
-        .doTest(TEXT_MATCH);
+        .doTest();
   }
 }