[GROOVY-5502] If/else branch does not always infer the variable type

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 2.0.0, 2.5.23, 4.0.14, 3.0.19
• Component/s: Static Type Checker
• Assignee: Unassigned
• Reporter: Ariel Morelli Andres
• Created: 06/Jun/12 09:41
• Updated: 22/Aug/23 12:51

Description

Suppose we have the following code:

class A {
  void m() {  
  }
}
class B extends A {
}
class C extends A {
}

@groovy.transform.TypeChecked
class Test {

   void m() {
      def var = new Object()   //If instead I put just "def var" it works as spected
      if (true) {
        var = new B()
      }
      else {
        var = new C()
      }
      var.m()                  //fails here
   }
}

In this case, after the if/else structure we can infer that var is instanceOf A.
But, the initialization seems to confuse the type inference.

[Static type checking] - Cannot find matching method java.lang.Object#mA()
at line: 23, column: 7

If instead of

def var = new Object()

we put just

def var

, then the inference works fine.

Issue Links

• is duplicated by: GROOVY-6503 Compiler should not fail if a var is assigned inside if-branches