rust-analyzer/docs/TOOLS.md

Tools used to implement libsyntax

libsyntax uses several tools to help with development.

Each tool is a binary in the tools/ package. You can run them via cargo run command.

cargo run --package tools --bin tool

There are also aliases in ./cargo/config, so the following also works:

cargo tool

Tool: gen

This tool reads a "grammar" from grammar.ron and generates the syntax_kinds.rs file. You should run this tool if you add new keywords or syntax elements.

Tool: 'parse'

This tool reads rust source code from the standard input, parses it, and prints the result to stdout.