Repository query projection not working as expected since 3.4.x

[jcedenopyx]

When using a MongoRepository<A, B>, query functions that project from type A to type C (with compatible fields), spring attempts to convert the full object to the Id field type.

This behavior worked fine until spring data 3.3.x. Using @Id or @MongoId on the Id field has no effect, but using @Field("_id") makes it so that it maps properly.

Demo reproducing the bug: https://github.com/jcedenopyx/spring-data-mongo-query-projection-issue/blob/master/src/test/java/me/jcedeno/demo/DemoApplicationTests.java#L89-L95

org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [me.jcedeno.demo.models.Transaction] to type [me.jcedeno.demo.models.TransactionId]
	at app//org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:322)
	at app//org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:195)
	at app//org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:175)
	at app//org.springframework.data.mapping.model.ConvertingPropertyAccessor.convertIfNecessary(ConvertingPropertyAccessor.java:121)
	at app//org.springframework.data.mapping.model.ConvertingPropertyAccessor.setProperty(ConvertingPropertyAccessor.java:64)
	at app//org.springframework.data.mongodb.core.convert.MappingMongoConverter.readAndPopulateIdentifier(MappingMongoConverter.java:574)
	at app//org.springframework.data.mongodb.core.convert.MappingMongoConverter.populateProperties(MappingMongoConverter.java:541)
	at app//org.springframework.data.mongodb.core.convert.MappingMongoConverter.doReadProjection(MappingMongoConverter.java:377)
	at app//org.springframework.data.mongodb.core.convert.MappingMongoConverter.project(MappingMongoConverter.java:323)
	at app//org.springframework.data.mongodb.core.MongoTemplate$ProjectingReadCallback.doWith(MongoTemplate.java:3348)
	at app//org.springframework.data.mongodb.core.MongoTemplate.executeFindMultiInternal(MongoTemplate.java:2959)
	at app//org.springframework.data.mongodb.core.MongoTemplate.doFind(MongoTemplate.java:2676)
	at app//org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.doFind(ExecutableFindOperationSupport.java:220)
	at app//org.springframework.data.mongodb.core.ExecutableFindOperationSupport$ExecutableFindSupport.all(ExecutableFindOperationSupport.java:163)
	at app//org.springframework.data.mongodb.repository.query.AbstractMongoQuery.lambda$getExecution$3(AbstractMongoQuery.java:178)
	at app//org.springframework.data.mongodb.repository.query.AbstractMongoQuery.doExecute(AbstractMongoQuery.java:152)
	at app//org.springframework.data.mongodb.repository.query.AbstractMongoQuery.execute(AbstractMongoQuery.java:127)
	at app//org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:137)
	at app//org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:121)
	at app//org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:160)
	at app//org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:139)
	at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at app//org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:76)
	at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at app//org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
	at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
	at app//org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:241) 

[christophstrobl]

Thanks for reporting and the reproducer. We'll have a look.

[jcedenopyx]

Thanks for fixing this so quick! Is this going out on October 13th?