Fetching map values with ok flag fails with panic

[carpawell]

func getFromMap(m map[string]any, key string) any {
	v, ok := m[key]
	if !ok {
		panic("'" + key + "'" + " not found")
	}

	return v
}

Current Behavior

Want safely check if map contains some value.

Expected Behavior

First, it panics: at instruction 2647 (STLOC1): runtime error: index out of range [-1]. Second, it does not work overall, why?

Possible Solution

Fix panic, support safe value fetching.

Steps to Reproduce

Try to compile snippet above.

Context

nspcc-dev/neofs-contract#448

Regression

Not sure.

Your Environment

v0.106.3

[AnnaShaleva]

We may use HASKEY for that in compiler. As a temporary solution, you may try to use neogointernal.Ocode2("HASKEY", m, key).(bool).

[carpawell]

Moreover, it is not possible to fetch missing value without exception: at instruction 2645 (PICKITEM): unhandled exception: "Key not found in Map". IMO, Map type is broken.

[roman-khimov]

Looks like we've never used maps in contracts.