[RefactorSwitch] flip flag to enable simplification of switches

PiperOrigin-RevId: 899771743

Author: markhbrady

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

@@ -1901,7 +1901,7 @@ ValidateCommonParams withSubject(Optional<ExpressionTree> subject) {
    * This record is an intermediate representation of a single `x instanceof Y` or `x instanceof Y
    * y` expression.
    */
-  record InstanceOfIr(
+  private record InstanceOfIr(
       // In the example above, the expression would be `y`.
       Optional<ExpressionTree> expression,
       // In the example above, the variable tree would be `Y y`.
@@ -1919,7 +1919,7 @@ record InstanceOfIr(
    * being synthesized. Its scope is roughly equivalent to a `CaseTree` in Java's AST, although does
    * not cover all of the same functionality.
    */
-  record CaseIr(
+  private record CaseIr(
       boolean hasCaseNull,
       boolean hasDefault,
       // The pattern, if any
@@ -1950,14 +1950,15 @@ record CaseIr(
    * Container for the subject (of an if predicate) and a (non-empty) list of expressions that can
    * match that subject in the given case.
    */
-  record SubjectAndCaseExpressions(ExpressionTree subject, List<ExpressionTree> expressions) {
+  private record SubjectAndCaseExpressions(
+      ExpressionTree subject, List<ExpressionTree> expressions) {
     SubjectAndCaseExpressions {
       checkArgument(!expressions.isEmpty());
     }
   }
 
   /** This record represents the current state of the analysis of an if-chain. */
-  record IfChainAnalysisState(
+  private record IfChainAnalysisState(
       // The expression to be switched on (if known)
       Optional<ExpressionTree> subjectOptional,
       // Depth of the if statement being analyzed (relative to the start of the if-chain)

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

@@ -106,7 +106,7 @@ public final class RefactorSwitch extends BugChecker
   RefactorSwitch(ErrorProneFlags flags) {
     enableAssignmentSwitch = flags.getBoolean("RefactorSwitch:EnableAssignmentSwitch").orElse(true);
     enableReturnSwitch = flags.getBoolean("RefactorSwitch:EnableReturnSwitch").orElse(true);
-    enableSimplifySwitch = flags.getBoolean("RefactorSwitch:EnableSimplifySwitch").orElse(false);
+    enableSimplifySwitch = flags.getBoolean("RefactorSwitch:EnableSimplifySwitch").orElse(true);
   }
 
   @Override

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

@@ -1821,7 +1821,7 @@ private static NullDefaultKind analyzeCaseForNullAndDefault(CaseTree caseTree) {
    * @param symbolsToHoist Bidirectional map from symbols to hoist to the top of the switch
    *     statement to their declaration trees
    */
-  record AnalysisResult(
+  private record AnalysisResult(
       boolean canConvertDirectlyToExpressionSwitch,
       boolean canConvertToReturnSwitch,
       boolean canRemoveDefault,
@@ -1839,7 +1839,7 @@ record AnalysisResult(
    * @param assignmentSourceCodeOptional Java source code of the assignment switch's operator, e.g.
    *     "+="
    */
-  record AssignmentSwitchAnalysisResult(
+  private record AssignmentSwitchAnalysisResult(
       boolean canConvertToAssignmentSwitch,
       Optional<VariableTree> precedingVariableDeclaration,
       Optional<ExpressionTree> assignmentTargetOptional,
@@ -1853,7 +1853,7 @@ record AssignmentSwitchAnalysisResult(
    * @param assignmentExpressionKindOptional Kind of the first assignment seen, if any
    * @param assignmentTreeOptional ExpressionTree of the first assignment seen, if any
    */
-  record AssignmentSwitchAnalysisState(
+  private record AssignmentSwitchAnalysisState(
       CaseQualifications assignmentSwitchCaseQualifications,
       Optional<ExpressionTree> assignmentTargetOptional,
       Optional<Tree.Kind> assignmentExpressionKindOptional,