[GROOVY-7763] Various problems with type inference in Groovy 2.4.6

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Duplicate
• Affects Version/s: 2.4.6
• Component/s: Static Type Checker
• Assignee: Unassigned
• Reporter: Graeme Rocher
• Created: 23/Feb/16 08:40
• Updated: 24/Jan/23 15:07
• Resolved: 27/Nov/19 15:35

Description

After trying to upgrade Grails to Groovy 2.4.6 there are numerous problems with @CompileStatic and type inference with Maps and Lists. If I had seen the vote for the release in time I would have tested and voted -1, so sorry for only reporting this afterwards.

This commits shows the changes I had to make in order to get Grails to compile with Groovy 2.4.6:

https://github.com/grails/grails-core/commit/a6d70aaf7925fb7f2e847a803a8e1f3c95bf8cf8

You can see for example that previously returning a list initialised with variables of the correct type compiled, but no longer does:

https://github.com/grails/grails-core/commit/a6d70aaf7925fb7f2e847a803a8e1f3c95bf8cf8#diff-3092a650525dc131a0394eca4282362bL35

Also empty lists and maps no longer seem to compile. See:

https://github.com/grails/grails-core/commit/a6d70aaf7925fb7f2e847a803a8e1f3c95bf8cf8#diff-07f8418b033d870eee3c1cee97e44f4cL121
https://github.com/grails/grails-core/commit/a6d70aaf7925fb7f2e847a803a8e1f3c95bf8cf8#diff-15a1d1d639cada3a0c85c7200547db02L40

Issue Links

• is related to: GROOVY-7598 type checking with generics
• is related to: GROOVY-7753 regression of return type from ternary operator
• relates to: GROOVY-10914 Method ambiguity error even if the given argument has an explicit type