array returned by function bypasses illegal sumtype conversion checker error

[Le0Developer]

V doctor:

V full version: V 0.4.7 62c69e8.caa0c46
OS: macos, macOS, 15.2, 24C101
Processor: 8 cpus, 64bit, little endian, Apple M2

getwd: /Users/leodev/p/v/cluedo
vexe: /Users/leodev/bin/v/v
vexe mtime: 2024-08-26 08:17:23

vroot: OK, value: /Users/leodev/bin/v
VMODULES: OK, value: /Users/leodev/.vmodules
VTMP: OK, value: /tmp/v_501

Git version: git version 2.39.5 (Apple Git-154)
Git vroot status: weekly.2024.34-46-gcaa0c464 (866 commit(s) behind V master)
.git/config present: true

CC version: Apple clang version 16.0.0 (clang-1600.0.26.6)
thirdparty/tcc status: thirdparty-macos-arm64 713692d4

What did you do?
./v -g -o vdbg cmd/v && ./vdbg repro.v

fn produce_array() []int {
	return [1, 2, 3]
}

type Sumtype = int | string

fn main() {
	mut x := []Sumtype{}
	x << produce_array()

	println(x)
}

What did you expect to see?

Checker error

What did you see instead?

[unknown sum type value, unknown sum type value, unknown sum type value]

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_{Huly®: V_0.6-21705}

[Le0Developer]

@felipensp this should be a checker error. if you do x << [1, 2, 3] without the function it already is, so this should too

[felipensp]

@felipensp this should be a checker error. if you do x << [1, 2, 3] without the function it already is, so this should too

Since x << [1,2,3] //produce_array() works fine, why not keep the behavior for array returned from function?

[Le0Developer]

Since x << [1,2,3] //produce_array() works fine

It doesn’t, it’s a checker error.