image/jpeg and image/png tests fail to build?

[dkegel-fastly]

I just cloned the repo and tried

cd image/jpeg
tinygo test

This failed with

reader_test.go:92:2: wrong number of return values (want 2, got 1)

It looks like an internal disagreement about the return values of Decode()... @sago35, could you comment?

[sago35]

@dkegel-fastly
I changed the interface from Go's image package.

https://github.com/tinygo-org/drivers/tree/release/examples/ili9341/slideshow

drivers/examples/ili9341/slideshow/main.go

Lines 66 to 76 in 90a13a6

	func drawPng(display *ili9341.Device) error {
	p := strings.NewReader(pngImage)
	png.SetCallback(buffer[:], func(data []uint16, x, y, w, h, width, height int16) {
	err := display.DrawRGBBitmap(x, y, data[:w*h], w, h)
	if err != nil {
	errorMessage(fmt.Errorf("error drawPng: %s", err))
	}
	})
	return png.Decode(p)
	}

However, it failed because I did not change the tests.

I think we can either maintain the test or remove it.

[dkegel-fastly]

I'd vote for fixing the test and turning it on in CI, on the theory that it helps prevent bitrot.

[deadprogram]

I changed the interface from Go's image package.

Is that strictly needed? I have not looked at the specifics in this case, just asking.

[sago35]

Is that strictly needed? I have not looked at the specifics in this case, just asking.

Due to memory size limitations, it was not possible to return image.Image.
I changed the function signature to make the user aware of the mistake, but in hindsight I think it would have been better to just return nil.

• Go's image/png : func Decode(r io.Reader) (image.Image, error)
• tinygo.org/x/image/png : func Decode(r io.Reader) error

I'd vote for fixing the test and turning it on in CI, on the theory that it helps prevent bitrot.

I'll take a look.