Odra 0.8.0: Business Class

Changed

• Replaced contract_env:: with self.env() in the contract context (of type ContractEnv).
  For example, instead of contract_env::caller() use self.env.caller().
• Replaced test_env with odra_test::env() in the test context (of type HostEnv).
• It is no longer possible to put a Mapping inside a Mapping. Use tuple keys instead, for example, instead of allowances: Mapping<Address, Mapping<Address, U256>> use allowances: Mapping<(Address, Address), U256>.
• Ref has been divided into two: HostRef and ContractRef depending on the context.
• Storage keys are constructed differently, keep that in mind when querying the storage outside the contract.
• token_balance(address: Address) in test context is now balance_of(address: &Address).
• Modules needs to be wrapped in SubModule<> when used in another module.
• HostRef (formerly Ref) methods parameters accept values even if endpoints expect references.
• unwrap_or_revert and unwrap_or_revert_with now require &HostEnv as a first parameter.
• Variable has been renamed to Var.
• Spent Gas is taken into account when checking an account balance.
  This means that all calls appear to cost 0 gas to the test accounts,
  but it is still possible to check the costs of the calls.
• Various changes of method signatures in odra-modules, e.g. &[U256] changed to Vec<U256>
  in on_erc1155_batch_received method.
• get_block_time() now returns u64 instead of wrapped type Blocktime(u64).
• The name property in Odra.toml is not required anymore.
• odra-casper-backend crate is now odra-casper-wasm-env
• odra-mock-vm crate is now odra-vm
• odra-proc-macros is the only code generation point.

Removed

• Removed #[odra::init] macro - now only one method can be a constructor,
  and it has to be named init.
• Removed emit() method from events. Use self.env.emit_event(event) instead.
• Removed assert_events! macro. Use env.emitted_event and similar methods instead.
• Removed native_token_metadata() and its respective structs.
• Removed assert_exception! macro. Use try_ prefix for endpoints instead. It returns a Result
  which can be used with a regular assert_eq! macro.`
• Removed odra(using) macro.
• Removed default() method from Deployer. Use init() instead.
• Removed StaticInstance and DynamicInstance traits. Use Module instead.
• Removed Node trait.
• Removed odra-types, odra-ir, odra-codegen, odra-casper-backend, odra-casper-shared, odra-utils crates.
• Removed OdraEvent trait, odra reexports casper_event_standard crate instead.

Added

• last_call() in test env with ContractCallResult struct which holds all information about the last call.
• odra::prelude::* module which reexports all basic types and traits.
  It is recommended to use it in the module code.
• odra-test crate providing HostEnv for testing purposes.
• odra-core crate providing framework core functionalities.
• odra-casper-rcp-client crate providing CasperClient for interacting with Casper node.
• odra-casper-livenet-env crate providing a host environment fo for the Casper livenet.
• HostRef trait - a host side reference to a contract.
• HostRefLoader trait for loading a contract from the host environment.
• EntryPointsCallerProvider trait.
• Deployer trait - a struct implementing that trait can deploy a contract.
• InitArgs trait - a struct implementing that trait can be used as a constructor argument.
• NoArgs struct, an implementation of InitArgs for empty/none (no constructor) arguments.

Very Brief Upgrade Path

• Copy bin folder and build.rs files from a freshly generated project
  using cargo-odra at version at least0.1.0.
• Update Cargo.toml by removing features and adding [[bin]] sections (See Cargo.toml from generated project).
• Update the code to reflect changes in the framework.

Full Changelog: 0.7.1...0.8.0