feat: showcase available storage types

[peetzweg]

Adds first draft of a contract to showcase all types which can be stored. Not an ink/rust expert so happy to get some review what to improve.

Types:

• u[8,16,32,64,128]
• i[8,16,32,64,128]
• struct
• enum
• bool
• Hash
• Balance
• AccountId
• Tuple
• Array
• Vec (ink-prelude)
• String (ink-prelude)
• Option Some
• Option None
• Result Ok
• Result Error
• Mapping (ink-storage)
• Custom data structure with #[ink::storage_item]

What else is available?

Even more types available via prelude => https://docs.rs/ink_prelude/latest/ink_prelude/

But afaik they are more useful for keeping internal contract state and are not exposed as returned values.

• HashMap (ink-prelude)
• BTreeMap (ink-prelude
• Lazy (ink-storage)
• ...

Origin:

We want such a contract to create some e2e tests showcasing all possible types available in ink for the contracts-ui. Related PR: use-ink/contracts-ui#449 .

[statictype]

there are also Option, Tuple, Array, bool

[peetzweg]

Hey @SkymanOne, can you have a look at this? Does this look okay'ish to you? Can it be a bit simpler somehow or other recommendations?

Is there a way to put mappings into a struct in ink?

https://github.com/paritytech/ink-examples/pull/15/files#diff-a89a9d0d60bbad817daaa9d021e559bd1142ef3c6b8fe02001b98a2c49e310b3R119-R122

I get an error along theses lines if I put a mapping in a struct with the same annotation as the others structs in the contract.

[peetzweg]

@statictype what do you think about this? I would consider this complete enough. Afaik it covers all types meant to be returned by contracts via messages. Stuff like Mappings and BTreeMap etc. from prelude don't seem built to be returned by ink messages and just for internal contract data.

If we call it complete I would add this contract as a e2e test to contracts-ui.

[peetzweg]

Okay just realized this PR should be into the ink repo itself. ed91979

The more I learn about rust and ink, the more I can appreciate the mother contract. Not to convinced off the use of the contract made in this pr anymore. Regarding giving complex storage examples this PR looks a bit more promising even. use-ink/ink#1592

What do you think about this @statictype ?

[statictype]

haven't compiled it yet but LGTM! One thing that is missing is something like revertOrTrap in the mother contract. it returns an error object (as opposed to error strings). We can add this later, your call.
It should live in the integration tests folder, indeed. We only use it for testing, not an actual example.

The more I learn about rust and ink, the more I can appreciate the mother contract. Not to convinced off the use of the contract made in this pr anymore

why? the mother contract was incomplete in terms of types and not very specific in terms of naming.

[peetzweg]

@statictype just added a get_panic message which just panics and together with the get_result_error message it should be the equivalent of the revert_or_trap function of the mother contract.

https://github.com/paritytech/ink-examples/blob/40fbf9d8082174ae11eed87482ed66d167125fec/storage_types/lib.rs#L235-L245

revert_or_trap in mother:
https://github.com/paritytech/ink/blob/bc4786ed4b2007d4b821aea40abb734373477266/integration-tests/mother/lib.rs#L172-L184

What I like about the mother contract is the fact that it's function just echo the input data. But this kind of functionality is maybe nice to have in a separate contract to test the sending of extrinsics from the contracts-ui. Whereas this contract is just focused on decoding the available return types.

Will create the pr for the ink repo now.

[peetzweg]

Closed in favor of use-ink/ink#1762.