[GROOVY-8411] Support instanceof-like flow typing for class literal switch case

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 5.0.0-alpha-1
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 11/Dec/17 15:57
• Updated: 23/Aug/23 09:11
• Resolved: 26/Nov/22 20:18

Description

Would it be possible to extend the maybeFile instanceof File ? maybeFile.canonicalPath : maybeFile.toString() flow typing where maybeFile is seen as File in the true expression position to work for switch?

This is the kind of construct I am thinking of:

  switch (maybeFile) {
  case File:
    maybeFile.canonicalPath
    break
  default:
    maybeFile.toString()
  }

Currently the example fails in an @TypeChecked or @CompileStatic scope, there is an error for the canonicalPath reference.

Issue Links

• is duplicated by: GROOVY-9470 Automatic type casting with switch..case with instanceof