Result of Regex.Match("wtfb",@"(.)()+?b") is not same as new Regex(@"(.)()+?b",RegexOptions.Compiled).Match("wtfb")

[longxia1995]

Description

If pattern includes ()+?, then Regex.Match(input,pattern) will match differnet new Regex(pattern ,RegexOptions.Compiled).Match(input)

Some discussions in GitHub Discussion #110976

Reproduction Steps

using System.Text.RegularExpressions;

string input = "wtfb";
string pattern="^(.)+()+?b";
Match matchInterpreted = new Regex(pattern, RegexOptions.None).Match(input);
Match matchCompiled = new Regex(pattern, RegexOptions.Compiled).Match(input);

Console.WriteLine($"Interpreted: {matchInterpreted.Value}");
Console.WriteLine($"Compiled: {matchCompiled.Value}");

Output:

Interpreted: b
Compiled: wtfb

Expected behavior

Output:

Interpreted: wtfb
Compiled: wtfb

Actual behavior

Output:

Interpreted: b
Compiled: wtfb

It looks like ()+? would make nearest outside brackets start at where the empty loop began, and this effect maybe gradually spread to group 0 or not.

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

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[DL444]

Interpreted: b

Typo in the expected behavior. It is expected that the interpreted result matches compiled.