RFR: JDK-8248641: Trees.getScope returns incorrect results for code inside a rule case

[Vicente Romero]

On 7/27/20 1:09 PM, Vicente Romero wrote:
> looks good, but shouldn't the test include cases for which the body is 
> not null?

hit the send button too soon, I meant, shouldn't the test explicitly 
check that the body is not null for the rest of the cases?
>
> Vicente
>
> On 7/27/20 8:46 AM, Jan Lahoda wrote:
>> Hi,
>>
>> The existing patch is always filling out the JCCase.body, even for 
>> statement cases (unlike the parser, which leaves the body empty/null 
>> for statement cases). While I don't think there's anything directly 
>> broken by this, it may be better to keep JCCase.body null for 
>> statement cases to keep consistency with the normal non-copied trees.
>>
>> Updated patch:
>> http://cr.openjdk.java.net/~jlahoda/8248641/webrev.01/
>>
>> What do you think?
>>
>> Thanks,
>>     Jan
>>
>> On 07. 07. 20 21:15, Vicente Romero wrote:
>>> looks good,
>>> Vicente
>>>
>>> On 7/2/20 9:11 AM, Jan Lahoda wrote:
>>>> Hi,
>>>>
>>>> When calling Trees.getScope for a TreePath that is inside a rule 
>>>> case (i.e. "case ->"), the results are wrong/do not reflect the 
>>>> elements declared inside the enclosing method.
>>>>
>>>> The reason is that, for rule cases, JCCase tree is keeping "body", 
>>>> which represents what is in the source code. And this body is 
>>>> wrapped and put into "stats", which are basically the statements 
>>>> for an ordinary case. This means that javac can typically only work 
>>>> over the "stats". When TreeCopied copies the JCCase tree, it will 
>>>> duplicate both "stats" and "body" separately, leading to a 
>>>> duplication in trees. And then Attr.breakTree points to the 
>>>> requested tree from "body", but that one is never attributed, and 
>>>> so the appropriate scope is never captured.
>>>>
>>>> The proposed patch here is to only duplicate "stats", and then take 
>>>> appropriate "body" from "stats", leading to only one copy of the tree.
>>>>
>>>> Webrev:
>>>> http://cr.openjdk.java.net/~jlahoda/8248641/webrev.00/
>>>>
>>>> JBS:
>>>> https://bugs.openjdk.java.net/browse/JDK-8248641
>>>>
>>>> How does this look?
>>>>
>>>> Thanks,
>>>>     Jan
>>>
>