miniconf-parser

MiniConf is a plain-text configuration format with simple sections and key = value pairs. This crate provides both a reusable parser library and a convenient CLI built on top of a pest grammar.

Features

• ✅ Declarative PEG grammar in src/grammar.pest with explicit support for sections, key/value pairs, comments, and arrays.
• ✅ Strongly-typed AST (Document, Section, Value) re-exported by the library.
• ✅ Helpful diagnostics powered by thiserror with duplicate-key detection.
• ✅ Batteries-included CLI for parsing or validating files plus JSON/pretty output modes.

Quick Start

Library

use miniconf_parser::parse_str;

let doc = parse_str("[service]\nport = 8080\n")?;
println!("sections: {}", doc.sections().count());

CLI

miniconf-parser parse config.mc            # pretty print
miniconf-parser parse config.mc -f json    # emit JSON
miniconf-parser check config.mc            # validate only

Grammar Highlights

1. section_header: [section_name] with alphanumeric, _, or - characters.
2. key_value: key = value with flexible whitespace and optional trailing comments.
3. comment_line: # comment to end-of-line, including inline comments.
4. value: quoted/bare strings, integers/floats, booleans (true/false/yes/no), and arrays like [one, two].

Development Workflow

• make fmt – format the codebase.
• make clippy – run cargo clippy -- -D warnings to keep lints clean.
• make test – execute the full test suite in tests/ plus doctests.
• make doc – build API docs (cargo doc --no-deps).
• make publish – sanity-check cargo publish --dry-run before releasing.

The test suite combines parser-focused cases (tests/parser_tests.rs) with CLI-level integration tests. Shared fixtures live under tests/common/. Examples in examples/ demonstrate typical embedding scenarios.

Documentation

Comprehensive rustdoc comments and doctests are enabled on docs.rs. Run cargo doc --open for a local copy. The CLI is implemented with clap 4.5, while the library exposes ergonomic error types so downstream applications can surface helpful diagnostics.