[GROOVY-9064] STC: explicit declared variable type ignored in favor of assigned value type(s)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0-alpha-3, 3.0.9
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 03/Apr/19 15:39
• Updated: 24/Jan/23 16:31
• Resolved: 04/May/21 21:53

Description

Follow up to GROOVY-9058.  Consider the following:

List getSomeRows() { ... }
@groovy.transform.CompileStatic
void meth() {
  List<Object[]> rows = getSomeRows()
  rows.each { row ->
    def col = row[0]
  }
}

The inferred type of rows is List and not List<Object[]> even though the assignment cleared type checking. This causes the inferred type of row to be Object instead of Object[].

Similarly, List<String> list = [] infers as ArrayList<String> instead of the explicit declared type, and Map<String, ?> map = [:] infers to LinkedHasMap<...> instead of the declared type. In general, I think as long as the assignment is compatible, the variable should retain its explicitly declared type regardless of assignments.

Issue Links

• relates to: GROOVY-10914 Method ambiguity error even if the given argument has an explicit type