[GROOVY-6429] flow typing detects unexpected error at if-else flow

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.2.0-rc-2, 2.3.0, 2.4.0-beta-3
• Fix Version/s: 5.0.0-alpha-1
• Component/s: Static Type Checker
• Assignee: Eric Milles
• Reporter: UEHARA Junji
• Created: 13/Nov/13 15:21
• Updated: 23/Jan/24 17:15
• Resolved: 27/Nov/22 20:10

Description

In groovy 2.2.0-rc-3, this code:

class A{
}
class B extends A{
    void foo(){}
}

@groovy.transform.TypeChecked
void test1(A x) {
    if (x instanceof B) {
        x.foo()
    }
}

@groovy.transform.TypeChecked
void test2(A x) {
    if (!(x instanceof B)) {
        return
    }
    x.foo()
}

@groovy.transform.TypeChecked
void test3(A x) {
    if (!(x instanceof B)) {
        return
    }
    else {
        x.foo()
    }
}
@groovy.transform.TypeChecked
void test4(A x) {
    if (!(x instanceof B)) {
        return
    }
    assert x instanceof B
    x.foo()
}

test1(new B())
test2(new B())
test3(new B())
test4(new B())

expects all OK. but test2 and test3 results in:

% groovy a.groovy
org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
/Users/uehaj/work/201311/comprehension_groovy/a.groovy: 19: [Static type checking] - Cannot find matching method A#foo(). Please check if the declared type is right and if the method exists.
@ line 19, column 5.
x.foo()
^

/Users/uehaj/work/201311/comprehension_groovy/a.groovy: 28: [Static type checking] - Cannot find matching method A#foo(). Please check if the declared type is right and if the method exists.
@ line 28, column 9.
x.foo()
^

2 errors

Issue Links

• is related to: GROOVY-8523 Static type checking instanceof
• is related to: GROOVY-9931 !instanceof inference does not work
• is related to: GROOVY-8412 Support !instanceof flow typing for else case
• relates to: GROOVY-11290 STC: multiple instanceof checks produce different results