error-context.js

const fs = require('fs');

const draw = (src, line, column, n) => {
	n = n || 3;
  const lines = src.split('\n');
  const start = Math.max(line - n, 0);
  const end = Math.min(lines.length, line + n);
  const context = lines.slice(start, end).map((text, i) => {
    const curr = start + i + 1;
    const out = `${curr} ${text}`;
    if(curr === line && column){
      out += '\n>' + '-'.repeat(column) + '^';
    }
    return out;
  }).join('\n');
  return context;
}


console.log(draw(fs.readFileSync('error-context.js', 'utf8'), 7, 24));

https://gist.github.com/song940/0e54610db7b134c95350aaf0dcc98608#file-error-context-js-L3
draw接受 file 怎么样