[GROOVY-9910] STC: no error for incorrect parameter type if not referenced in lambda

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 4.0.0-rc-1
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 26/Jan/21 17:31
• Updated: 06/Jun/23 18:31
• Resolved: 06/Jun/23 18:31

Description

Follow up to GROOVY-9790. If a lambda expression does not reference one of its parameters, no inferred type metadata is written to the parameter and the boostrap error can still occur.

Consider the following:

            @groovy.transform.CompileStatic
            void test1() {
                java.util.stream.IntStream.range(0, 2).forEach(
                    (Integer i) -> {  } // no reference to "i"
                )
            }
            @groovy.transform.CompileStatic
            void test2() {
                java.util.stream.IntStream.range(0, 2).forEach(
                    (String s) -> { assert false } // no reference to "s"
                )
            }

9790 fixes depend of the inferred type of a variable expression being written back to accessed variable (the parameter).

Issue Links

• relates to: GROOVY-10372 STC: check lambda or closure parameter types against target method