badness-parser

The parser behind badness, a formatter, linter, and language server for LaTeX — extracted so that other tools can embed it.

It is a generic, error-tolerant, hand-written recursive-descent parser in the rust-analyzer mold: it treats input as TeX surface syntax and always produces a lossless rowan concrete syntax tree (reconstruct(text) == text, byte for byte), with errors carried alongside the tree instead of aborting it. It covers LaTeX (.tex, .sty/.cls, .dtx, .ins) and, in the bib module, BibTeX/BibLaTeX (.bib) as a parallel pipeline on the same architecture.

Semantics live in the semantic module as a separate layer over the CST: a command-signature database (arity, verbatim-ness, sectioning — including a generated signature tier for thousands of package commands), definition scanning, expl3 support, labels, and document outlines. Meaning reaches the grammar only through a small set of curated routing facts; everything else stays in this layer.

The crate builds for wasm32-unknown-unknown.

Entry points: parser::parse / parser::parse_with_flavor, bib::parse, semantic::SemanticModel::build, and the typed wrappers in ast.

See the architecture documentation for the design.