Providing Multiple Ranges can lead to a edge-case issues

[muhammadtalhas]

Hello, I ran into this issue while scheduling a task to run every X minutes between the hours of 0-2,10-23

It showed sporadic behavior, working sometimes but not other times. The issue is in the range conversion file. I have a fix for it and Ill open a PR, just wanted to post this issue for documentation purposes. Below is a snippet of some code taken from range-conversion (I modified it a bit to show where the issue arises.)

function replaceWithRange(expression, text, init, end) {

        var numbers = [];
        var last = parseInt(end);
        var first = parseInt(init);
        console.log(`first ${first}`)
        console.log(`last ${last}`)


        if (first > last) {
            last = parseInt(init);
            first = parseInt(end);
        }

        for (var i = first; i <= last; i++) {
            numbers.push(i);
        }
        console.log(`numbers ${numbers}`)
        console.log(`expression before actual replace  ${expression}`)
        console.log(`expression after  ${expression.replace(new RegExp(text, 'gi'), numbers.join())}`)

        return expression.replace(new RegExp(text, 'gi'), numbers.join());
    }    
    
    
    
    function convertRange(expression) {
        console.log(`expression  ${expression}`)
        var rangeRegEx = /(^\d+)\-(\d+)/;
        var match = rangeRegEx.exec(expression);
        console.log(`match  ${match}`)
        console.log(`expression after exec  ${expression}`)


        while (match !== null && match.length > 0) {
            console.log(`replaceWithRange(${expression}, ${match[0]}, ${match[1]}, ${match[2]})`)
            expression = replaceWithRange(expression, match[0], match[1], match[2]);
            console.log(`expression after replace  ${expression}`)
            match = rangeRegEx.exec(expression);
        }
        console.log(`expression final  ${expression}`)
        console.log(' ')
        return expression;
    }

    
    console.log(`Original: 0-2,10-23`)
    console.log(` `)
    console.log(`Final: ${convertRange('0-2,10-23')}`)

Heres the output:

Original: 0-2,10-23
 
expression  0-2,10-23
match  0-2,0,2
expression after exec  0-2,10-23
replaceWithRange(0-2,10-23, 0-2, 0, 2)
first 0
last 2
numbers 0,1,2
expression before actual replace  0-2,10-23
expression after  0,1,2,10,1,23
expression after replace  0,1,2,10,1,23
expression final  0,1,2,10,1,23
 
Final: 0,1,2,10,1,23

You can see the output seems to not parse the second range correctly. It seems the replace function uses the g (global) option to replace the original expression everywhere its found. In our case, the original 0-2 also appears in 10-23 ( 1[0-2]3 ) and the next time the loop run, it dosen't find anything that needs to be replaced.