1 /*

     2  * @test /nodynamiccopyright/

     3  * @bug 8206986

     4  * @summary Check types inferred for switch expressions.

     5  * @compile/fail/ref=ExpressionSwitchInfer.out -XDrawDiagnostics --enable-preview -source 12 ExpressionSwitchInfer.java

     6  */

     7 

     8 import java.util.ArrayList;

     9 import java.util.List;

    10 

    11 public class ExpressionSwitchInfer {

    12 

    13     private static final String NULL = "null";

    14 

    15     private <T> T test(List<T> l, Class<T> c, String param) {

    16         test(param == NULL ? new ArrayList<>() : new ArrayList<>(), CharSequence.class, param).charAt(0);

    17         test(param == NULL ? new ArrayList<>() : new ArrayList<>(), CharSequence.class, param).substring(0);

    18 

    19         test(switch (param) {

    20             case NULL -> new ArrayList<>();

    21             default -> new ArrayList<>();

    22         }, CharSequence.class, param).charAt(0);

    23         test(switch (param) {

    24             case NULL -> new ArrayList<>();

    25             default -> new ArrayList<>();

    26         }, CharSequence.class, param).substring(0);

    27 

    28         String str = switch (param) {

    29             case "" -> {

    30                 break 0;

    31             } default ->"default";

    32         };

    33 

    34         return null;

    35     }

    36 

    37 }