[
https://issues.apache.org/jira/browse/GROOVY-11508?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17892803#comment-17892803
]
ASF GitHub Bot commented on GROOVY-11508:
-----------------------------------------
jamesfredley opened a new pull request, #2117:
URL: https://github.com/apache/groovy/pull/2117
https://issues.apache.org/jira/browse/GROOVY-11508
This PR converts the `RuntimeParserException`, which stops compilation, to a
more detailed warning about using a `Trait` or `Interface` with more than one
generic type parameter via inheritance.
Resolves https://github.com/grails/grails-data-mapping/issues/1811 which is
a significant open issue for the Groovy 3.0.x to 4.0.x upgrade in preparation
for Grails 7. Grails 6 and lower were still on Groovy 3.0.x.
Precise simplified example of the code which results in the exception with
Groovy 4.0.x compiler:
https://github.com/grails/grails-data-mapping/issues/1811#issue-2481317054
https://github.com/grails/grails-data-mapping/issues/1811#issuecomment-2419515195
- the decompiled Grails Domain Classes, compiled with Groovy 4.0.23, after
changing the exception to a warning. These Grails Domains, with inheritance,
compile and run without issue once the exception is removed during
pre-compilation verification.
In each instance the `Trait` or `Interface` which is implemented with 2+
generic types via inheritance, have generic types which are compatible and
extend in a lineage hierarchy.
The Groovy 4 compiler only copies the lowest level Trait or Interface
methods into the class, before compiling, which was the approach in Groovy 3
and same and expected approach in Groovy 4.
Example output after restoring Domain Inheritance and Inheritance tests on
https://github.com/grails/grails-data-mapping/
```
> Task :grails-datastore-gorm-tck:compileGroovy
Warning: on grails.gorm.tests.City the interface GormEntity was implemented
more than once with different arguments:
org.grails.datastore.gorm.GormEntity<grails.gorm.tests.City> and
org.grails.datastore.gorm.GormEntity<grails.gorm.tests.Location>,
grails.gorm.tests.City will only implement the lowest level GormEntity
Warning: on grails.gorm.tests.City the interface GormEntityApi was
implemented more than once with different arguments:
org.grails.datastore.gorm.GormEntityApi<grails.gorm.tests.City> and
org.grails.datastore.gorm.GormEntityApi<grails.gorm.tests.Location>,
grails.gorm.tests.City will only implement the lowest level GormEntityApi
Warning: on grails.gorm.tests.City the interface Entity was implemented
more than once with different arguments:
grails.gorm.Entity<grails.gorm.tests.City> and
grails.gorm.Entity<grails.gorm.tests.Location>, grails.gorm.tests.City will
only implement the lowest level Entity
Warning: on grails.gorm.tests.Country the interface GormEntity was
implemented more than once with different arguments:
org.grails.datastore.gorm.GormEntity<grails.gorm.tests.Country> and
org.grails.datastore.gorm.GormEntity<grails.gorm.tests.Location>,
grails.gorm.tests.Country will only implement the lowest level GormEntity
Warning: on grails.gorm.tests.Country the interface GormEntityApi was
implemented more than once with different arguments:
org.grails.datastore.gorm.GormEntityApi<grails.gorm.tests.Country> and
org.grails.datastore.gorm.GormEntityApi<grails.gorm.tests.Location>,
grails.gorm.tests.Country will only implement the lowest level GormEntityApi
Warning: on grails.gorm.tests.Country the interface Entity was implemented
more than once with different arguments:
grails.gorm.Entity<grails.gorm.tests.Country> and
grails.gorm.Entity<grails.gorm.tests.Location>, grails.gorm.tests.Country will
only implement the lowest level Entity
```
> Multiple traits with related generic types cannot be used
> ---------------------------------------------------------
>
> Key: GROOVY-11508
> URL: https://issues.apache.org/jira/browse/GROOVY-11508
> Project: Groovy
> Issue Type: Bug
> Components: Compiler
> Affects Versions: 4.0.0
> Reporter: James Daugherty
> Assignee: Eric Milles
> Priority: Major
> Attachments: screenshot-1.png, screenshot-2.png, screenshot-3.png
>
>
> When updating Grails from Groovy 3.x to 4.x we discovered that GROOVY-5106
> prevents us from updating to Groovy 4 for the
> [grails-data-mapping|https://github.com/grails/grails-data-mapping] (GORM)
> project. Groovy-5106 does not take into account relationships between
> generic types and groovy does not support inheritance in generic types on
> traits so we have no workable solution for using Groovy 4.
>
> For example, the following is not possible in Groovy 4:
> {code:java}
> class Parent extends GormEntity<Parent> {
> }
> class Child extends GormEntity<Child> {
> }
> class GormEntity<? extends GormEntity> { // ? extends GormEntity is not
> allowed
> }{code}
>
> We have documented the impacts of this issue on the grails-data-mapping
> project here: [https://github.com/grails/grails-data-mapping/issues/1811]
> We have discovered that the original change could be reverted and continue to
> work with the latest Java & Groovy.
>
> For Grails Data Mapping (GORM), there is support for inheritance between a
> Parent & Child domain object. This is often implemented like this:
> {code:java}
> class Parent extends GormEntity<Parent> {
> }
> class Child extends GormEntity<Child> {
> }
> trait GormEntity<D> { // Simplified for this ticket
> static D get(Serializable id)
>
> static List<D> getAll()
> }
> {code}
> This allows someone to do the following in code:
> {code:java}
> Parent.get(1L) // Will find either a Child or Parent
> Child.get(1L) // Will find only child types{code}
>
> Since Groovy-5106 does not take into account inheritance, can this change be
> reverted or changed to a warning until inheritance is taken into account?
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
