'use strict';
var _ = require('lodash'),
temp = require('temp'),
fs = require('fs'),
exec = require('child_process').exec;
// Automatically track and cleanup files at exit
temp.track();
// Perform a comparison between a and b
// the callback should have parameters (err, result)
module.exports = function(a, b, asMarkdown, callback) {
//!!! this nested file-open is not a good pattern
// better would be to use promises and write the two files asynchronously
// open the first file
temp.open('wdiffa-', function(err, filea) {
//handle errors
if (err)
return callback(err);
//write the string to the file
fs.write(filea.fd, a);
//close the file
fs.close(filea.fd, function(err) {
if (err)
return callback(err);
//open the second file
temp.open('wdiffa-', function(err, fileb) {
if (err)
return callback(err);
//write the string to the file
fs.write(fileb.fd, b);
//close the file
fs.close(fileb.fd, function(err) {
if (err)
return callback(err);
var cmd = "./bin/wdiff " + filea.path + " " +fileb.path;
exec(cmd, function(err, stdout) {
if (err && err.code!=1 && err.code!=0) {
return callback(err);
}
//if no difference was found by wdiff, err.code will be 0
var wdiffSame;
wdiffSame = (err && err.code == 0) ? true:false;
var resData = {wdiff:stdout, same: wdiffSame};
if (asMarkdown) {
//!!! this needs more sophisticated parsing
//sub del and ins for the wdiff tags
var markdown = stdout;
markdown = markdown.replace(/\[-/g, '');
markdown = markdown.replace(/-\]/g, '');
markdown = markdown.replace(/{\+/g, '');
markdown = markdown.replace(/\+}/g, '');
resData.wdiff=markdown;
}
return callback(null, resData);
});
});
});
});
});
}