[patterns-record-deconstruction3] RFR: Fix deconstruction patterns with unconditional nested type pattern

[Aggelos Biboudis]

On Mon, 25 Apr 2022 07:09:13 GMT, Jan Lahoda <jlahoda at openjdk.org> wrote:

>> According to the spec:
>> 
>> 
>> class Super {}
>> class Sub extends Super {}
>> record R(Super s) {}
>> 
>> public static void testRes(R r) {
>>     switch(r) {
>>        case R(Super s) -> System.out.println("a");
>>     }
>> }
>> 
>> testRes(new R(null)); // this should match since after resolution, the nested type pattern is transformed to an any pattern
>
> src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransPatterns.java line 310:
> 
>> 308:                 }
>> 309:                 else
>> 310:                     extraTest = makeLit(syms.booleanType, 1);
> 
> Thanks for working on this.
> 
> A few general comments here:
> - we usually put `else` at the same line as the preceding closing `}`, e.g. `} else`.
> - we usually put `{}` around the else section when there are brackets around the then section
> - we normally don't (currently) use `instanceof` to check AST node types - we usually use `JCTree.hasTag` or `JCTree.getTag`.
> 
> Here, seems this would work as well, right?
> 
>             } else if (nested.type.isReference() && nested.hasTag(Tag.DECONSTRUCTIONPATTERN)) {
>                 extraTest = makeBinary(Tag.NE, make.Ident(nestedTemp), makeNull());
>             }

Thank you @lahodaj 

Addressed.

-------------

PR: https://git.openjdk.java.net/amber/pull/81