todo

TODO

A library for parsing structured TODO comments from code.

Overview

• Tree-Sitter is used to parse comments from source files.
• A simple recursive descent parser then extracts and interprets TODO lines.

Syntax

TODO can appear anywhere in a comment line; anything before TODO is ignored. Once TODO is found:

1. An optional comma-separated list of attributes can follow, enclosed in parentheses.
2. A colon (:) must appear next.
3. Everything after the colon is the description.

Examples

// TODO: no attributes
// TODO(foo,bar): two key-only attributes
// TODO(created=2025-03-09, assigned=john): multiple key/value
// TODO(deadline="June 2025"): quoted value 

Grammar

todo-line  ::= (any text) "TODO" [ "(" attributes? ")" ] ":" description
attributes ::= attribute [ "," attribute ]*
attribute  ::= bare-key | key-value
key-value  ::= bare-key "=" (bare-key | quoted-value)
description ::= (any text to end of line)
bare-key   ::= (any non-whitespace sequence without parentheses, commas, or '=')
quoted-value ::= "\"" (any text) "\""

API Usage

package main

import (
	"os"
	"fmt"

	"github.com/icholy/todo"
)

func main() {
	// read file source
	file := "./main.go"
	source, _ := os.ReadFile(source)

	// parse todos
	todos, _ := todo.Parse(file, source)

	// print todos with deadlines
	for _, t := range todos {
		if _, ok := t.Attribute("deadline"); ok {
			fmt.Println(t)
		}
	}
}

CLI Tool

A minimal CLI tool is provided to parse and output these comments as JSON.

Installation

go install github.com/icholy/todo/cmd/todo@latest

Usage Example

todo ./**/*.go
./todo.go:88 TODO: investigate compilation error