markdown-to-ast/src/markdown-parser.js

Parse Markdown to AST with location info.

// LICENSE : MIT
"use strict";
const traverse = require("traverse");
const { ASTNodeTypes } = require("@textlint/ast-node-types");
const StructuredSource = require("structured-source");
const debug = require("debug")("markdown-to-ast");
const SyntaxMap = require("./mapping/markdown-syntax-map");
const remarkAbstract = require("remark");
const remark = remarkAbstract();
/**
 * parse markdown text and return ast mapped location info.
 * @param {string} text
 * @returns {TxtNode}
 */
function parse(text) {
    const ast = remark.parse(text);
    const src = new StructuredSource(text);
    traverse(ast).forEach(function(node) {
        // eslint-disable-next-line no-invalid-this
        if (this.notLeaf) {
            if (node.type) {
                const replacedType = SyntaxMap[node.type];
                if (!replacedType) {
                    debug(`replacedType : ${replacedType} , node.type: ${node.type}`);
                } else {
                    node.type = replacedType;
                }
            }
            // map `range`, `loc` and `raw` to node
            if (node.position) {
                const position = node.position;
                const positionCompensated = {
                    start: { line: position.start.line, column: position.start.column - 1 },
                    end: { line: position.end.line, column: position.end.column - 1 }
                };
                const range = src.locationToRange(positionCompensated);
                node.loc = positionCompensated;
                node.range = range;
                node.raw = text.slice(range[0], range[1]);
                // Compatible for https://github.com/wooorm/unist, but hidden
                Object.defineProperty(node, "position", {
                    enumerable: false,
                    configurable: false,
                    writable: false,
                    value: position
                });
            }
        }
    });
    return ast;
}
module.exports = {
    parse,
    Syntax: ASTNodeTypes
};