// This test should pass without crashing.

function testRegExp(re, str, expected)
{
    let match = re.exec(str);

    let errors = "";
    
    if (match) {
        if (!expected)
            errors += "\nExpected no match, but got: " + match;
        else {
            if (match.length != expected.length)
                errors += "\nExpected to match " + expected.length - 1 + " groups, but matched " + match.length - 1 +  " groups.\n";
            if (match[0] != expected[0])
                errors += "\nExpected results \"" + expected[0] + "\", but got \"" + match[0] + "\"";

            let checkLength = Math.min(match.length, expected.length);
            for (i = 1; i < checkLength; ++i) {
                if (match[i] != expected[i])
                    errors += "\nExpected group " + (i - 1) + " to be \"" + expected[i] + "\", but got \"" + match[i] + "\"";
            }
        }
    } else if (expected)
        errors += "\nExpected a match of " + expected + ", but didn't match";

    if (errors.length)
        throw errors.substring(1);
}

testRegExp(/^(.)\1*(\1.)/, "    ", ["    ", " ", "  "]);
testRegExp(/^(.)\1*(\1+?)a/, "    ", undefined);

testRegExp(/^(.)\1*?(.+)/, "xxxx", ["xxxx", "x", "xxx"]);

testRegExp(/^(.{2})\1*(.+)/, "xxxx", ["xxxx", "xx", "xx"]);
testRegExp(/^(.{2})\1*?(.+)/, "xxxx", ["xxxx", "xx", "xx"]);

testRegExp(/^(.{2})\1*(.+)/, "xxx", ["xxx", "xx", "x"]);
testRegExp(/^(.{2})\1*?(.+)/, "xxx", ["xxx", "xx", "x"]);

testRegExp(/^(.)\1*(.+)/s, "=======", ["=======", "=", "="]);
testRegExp(/^(.)\1*?(.+)/s, "=======", ["=======", "=", "======"]);

testRegExp(/^(.)\1*(X)/s, "======X", ["======X", "=", "X"]);
testRegExp(/^(.)\1*?(X)/s, "======X", ["======X", "=", "X"]);