Meadow

An Ethereum implementation and tool suite designed for Solidity testing and development. The unit testing framework provides fast parallelized test execution, built-in code coverage reporting, strongly typed Contract interfaces with powerful code-completion, Solidity stacktraces for reverts and exceptions, breakpoint debugging and more.

Written completely in cross-platform C# with .NET Core. Meadow can be used in VS Code, Visual Studio, and JetBrains Rider.

Builds	Windows Status	MacOS Status

Quick start

Install .NET Core SDK v2.1.4 or higher, then run these commands in a new directory for your project:

dotnet new -i Meadow.ProjectTemplate
dotnet new meadow

Open your project directory in VSCode or your favorite C# IDE.

Guides

• Writing unit tests - getting started writing tests against Solidity contracts and generating code coverage reports.

• Using the CLI - contract deployment and interaction against testnode or production.

• VSCode Solidity Debugger

• Solidity Coverage Report

• Configuration - Specifying gas defaults, solc version, solc optimizer, accounts, RPC host, unit test parallelism, etc..

• Usage examples; miscellaneous - ABI & RLP encoding, ECSign / ECRecover, testing reverts, etc..

Powerful Solidity contract development, deployment, and interaction

Provides an intuitive framework for writing C# to perform contract deployments, transactions, function calls, RPC requests, and more. Solidity source files are automatically compiled and exposed as C# classes with all contract methods, events, and natspec documentation. Includes a personal Ethereum test node that automatically is setup during test executions.

Visibility into Solidity revert / exception call stacks

Better understanding and investigation of Solidity execution problems.

Solidity Coverage Reports

Perform thorough testing of Solidity codebases. Generate HTML and JSON code coverage reports showing .sol source code coverage for line, branch, and function execution.

Solidity Debugger

Solidity debugger extension for Visual Studio Code supporting breakpoints, stepping, rewinding, call stacks, local & state variable inspection.

Components

Library	Description
Meadow.EVM	An Ethereum Virtual Machine that includes: Instructions/opcodes, calling conventions/messages/return values, memory/stack, logs/events, gas, charges/limits, precompiles, contract creation logic. Core Ethereum components: account storage, transaction receipts, transaction pool, blocks, world state, snapshoting/reverting, chain, mining/consensus mechanism/scoring/difficulty/uncles. Underlying dependencies: configuration/genesis block/fork/versioning/chain ID support, modified Merkle Patricia Trees, bloom filters, elliptic curve signing + public key recovery, Ethash, in-memory storage database.
Meadow.TestNode	Ethereum "personal blockchain" / "test node" / "RPC Server" / "Ethereum client". Ran as either a standalone server or via programmatic setup / teardown during unit test execution. Supports several non-standard RPC methods for debugging, testing, and coverage report generation.
Meadow.TestNode.Host	Standalone test RPC node/server used as a command line tool.
Meadow.SolCodeGen	Tool that compiles Solidity source files and generates a C# class for each contract. All public methods and events in the contract ABI are translated to corresponding idiomatic C# methods and event log classes. Solidity NatSpec comments / docs are also translated to IntelliSense / code-completion tooltips. This nuget package can be simply added to a project and Solidity files in the project contracts directory are automatically compiled.
Meadow.CoverageReport	Generates HTML and JSON code coverage reports for Solidity source files. Uses execution trace data from the EVM.
Meadow.UnitTestTemplate	Test harness providing seamless integration between MSTest and Solidity contracts. Provides a simple workflow where Solidity source files are dropped into a unit test project and C# contract code is automatically generated. C# unit tests can easily deploy/call/transact with contracts. RPC test node servers & clients are automatically boostrapped and provided to unit tests. Code coverage reports are automatically generated after unit tests are ran.
Meadow.Cli	Tool that allows contract deployments and interaction through the command line. Solidity source files are live-compiled using a file system watcher. Can be ran against a automatically bootstrapped test RPC node or an externally configured node. Leverages PowerShell Core to a provide cross platform REPL-like environment with powerful tab-completion when interacting with contracts.
Meadow.Core	RLP and ABI encoding & decoding utils. Implementations of Ethereum / solidity types such as Address, UInt256, Hash, etc. BIP32, BIP39, BIP44, HD account derivation implementation. Fast managed Keccak hashing. ECDSA / secp256k1 utils.
Meadow.JsonRpc	.NET types for the Ethereum JSON-RPC request & response data structures. .NET interface for all RPC methods. Serialization for JSON/hex object formats <-> Solidity/.NET types.
Meadow.JsonRpc.Client	JSON-RPC client implementation, supported transports: http, WebSocket, and IPC.
Meadow.JsonRpc.Server	Fast and lightweight HTTP and WebSockets JSON-RPC server - using Kestrel and managed sockets.