This project provides the necessary glue to invoke a NEAR contract inside a Web Browser's WASM runtime. Among other things that allows seamless use of the Web Developer Tools for use in debugging the execution of WASM code.
While this codebase does share a lot of code with the reference implementation of the NEAR
protocol, there may inevitably be certain differences in order to enable easier debugging
experience (e.g. the log_utf8 host function call will print to the console via console.log.)
For most intents and purposes the behaviour should be close enough however.
Currently the project is in very early development stages, but it does work with some patience and care.
neardebug is deployed to GitHub Pages and is accessible at https://near.github.io/neardebug/.
It is recommended to use Chromium for debugging: it has support for DWARF debug info which will show you the source code for your contract in the debugger, provided you have compiled your contract with debug info enabled. At the same time Firefox works better in some other ways. If using Chromium be interested in the C/C++ devtools support (DWARF) extension.
First open the Web Browser's Web Developer Tools (try Ctrl+Shift+I or Cmd+Shift+I,) then select
your contract, the method to invoke and press Execute!. Depending on your contract code you may
need to modify the execution context as well.
The console will output log messages and any errors that occur as a result of executing the contract. You can also place breakpoints and/or request the browser to stop execution on any uncaught exceptions as well.
window.contract is made available with some information about the contract and its execution as
well. For instance window.contract.logic.outcome() will show you the outcome you would see on the
chain when executing the contract on the real network (or testnet.)