sc 0.51.0, codec 0.20.0, vm 0.9.0, sdk 0.5.0, scenario-format 0.22.3

• Major refactoring of multiversx-sc-meta
  • Crate multiversx-sc-meta split in 2:
    1. multiversx-sc-meta remains the standalone tool. For backwards compatibility, it can still be used in contract meta crates, but a warning will be issued.
    2. multiversx-sc-meta-lib is the contract-only library to contract meta crates.
  • The refactoring came with few code changes, but dependencies were disentangled and cleaned up.
  • Account retrieval tool was merged into sc-meta standalone. Previously little known feature, it enables downloading the full state of an account and formatting it as a mandos set state step. Very useful for generating tests and investigating state.
  • multiversx-sdk was also refactored, especially the gateway proxy.
• A new code report is available in the .mxsc.json build output. The report analyzes the wasm code after build and always offers the following information:
  • imports: what VM hooks are used;
  • eiCheck: if the used imports comply with the environment interface (EI, allowed VM hooks);
  • hasAllocator: is it allocates on the heap;
  • hasPanic: whether it produces Rust panics and formats error messages using the standard Rust formatter (a source of code bloat).
• ManagedDecimal and ManagedDecimalSigned:
  • New types that encapulate a managed BigUint and BigInt respectively, but treat them as base 10 fixed point rational numbers.
  • Two flavors are allowed: the number of decimals is known at compile time (e.g. EGLD always has 18 decimals), or only at runtime.
    • Type ConstDecimals is able to resolve conversions at compile time, reducing code size and making encoding and decoding easier, since the number of decimals does not need to be encoded.
    • Regular usize number of decimals is resolved at runtime.
  • All basic arithmetic operations are implemented for these types, just like for the big integers.
• Implemented logarithms:
  • Natural logarithm ln for ManagedDecimal, BigFloat, and BigInt.
  • Base 2 logarithm log2 for ManagedDecimal.
  • Precision is about 5 decimals, largely irrespective of input.
  • The operation is cheap, ln costs 44980 gas for managed decimals and 153772 for big floats, largely irrespective of input.
• Smart contract code on the front-end:
  • Framework and contract code, together with the Rust VM as a backend, can now be compiled to WebAssembly for front-end, using wasm-bindgen.
  • A few incompatible Rust VM features needed to be made optional for this to work.
• Reverted changes in sc 0.50.6 (diagnostic::on_unimplemented & rustc 1.78 dependency).
• Bugfix: sync_call_readonly can now be used with proxies.