[GROOVY-8321] !instanceof treated incorrectly in type checker

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-rc-1
• Component/s: Static Type Checker
• Assignee: Unassigned
• Reporter: Paul King
• Created: 16/Sep/17 04:02
• Updated: 27/Nov/22 19:39
• Resolved: 29/Oct/19 19:07

Description

Currently in:
https://github.com/apache/groovy/blob/183b8fbf0248a2dceffbba684e50c3c2c060e46c/src/main/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java#L703

The `instanceof` and `!instanceof` operators are treated the same when in fact the exact opposite is required.

Consider the following code where the `instanceof` has been accidentally replaced with `!instanceof`.

[42, 'bar'].each { doit(it) }

@groovy.transform.TypeChecked
doit(arg) {
  if (arg !instanceof String) {
    println arg.toUpperCase() // MME: Integer.toUpperCase()
  } else {
    // println arg.toUpperCase() // [STC] [Static type checking] - Cannot find Object#toUpperCase()
    println 'is a number'
  }
}

We'd now expect the `toUpperCase` call to fail compilation but it succeeds and then fails at runtime.

Bonus points if the commented line in the else clause can be made to work.

Issue Links

• is related to: GROOVY-8523 Static type checking instanceof