[GROOVY-8687] STC: Support flow typing for (a.class == C && a...) and similar expressions

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: Static Type Checker
• Assignee: Unassigned
• Reporter: Eric Milles
• Created: 05/Jul/18 23:15
• Updated: 05/Jul/18 23:15

Description

Is it possible to extend the x instanceof C && x.methodOfC() flow typing to include:

• x.class == C && x...
• x.getClass() == C && x...
• x.getClass() === C && x...
• x.getClass().is(C) && x...
• and maybe even isCase and in?

Example:

@TypeChecked
def m(def obj) {
//def a = (obj instanceof String    && obj.equalsIgnoreCase('a'))
  def b = (obj.getClass() == String && obj.equalsIgnoreCase('b'))
  def c = (obj.class == String      && obj.equalsIgnoreCase('c'))
  def d = (obj.class.is(String)     && obj.equalsIgnoreCase('d'))
  def e = (obj.class.isCase(String) && obj.equalsIgnoreCase('e'))
  def f = (obj in [String, StringBuffer] && obj.somethingFromLUB()) // bonus
}