whereisline.js

const fs = require('fs');

`
# README
This program outputs line number and this contents to output file.

keys file formats as:
item.foo.name
block.bar.name
...
[EOF]

`;

if (process.argv.length < 5) {
    console.error("use : node ./whereisline <lang file path> <keys file path> <output file path>");
    return;
}

const [lpath, kpath, opath]
    = [process.argv[2], process.argv[3], process.argv[4]];

let langs = fs.readFileSync(lpath, 'utf-8')
    .split('\n')
    .map(e => e.replace(/\r$/, ''));
let keys = fs.readFileSync(kpath, 'utf-8')
    .split('\n')
    .map(e => e.replace(/\r$/, ''));

let res = langs
    .map((lang, index) => {
        const c = keys.filter(key => lang.startsWith(key));
        return c.length > 0 ? { line: index, entry: lang } : null;
    })
    .filter(l => l != null)
    .map(l => `${("0000" + l.line).slice(-4)} : ${l.entry}`).join("\n");

fs.writeFileSync(opath, res);