Use regex for generating string when regex pattern is found #778

[Markoutte]

Description

Now fuzzer searches for regexes from these places:

String.matches(regex)
Pattern.*(regex)

If any is found then it generates and mutates string values using found regex.

Fixes #778

Type of Change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Automated Testing

org.utbot.framework.plugin.api.ModelProviderTest

Manual Scenario

Try this example with only fuzzing:

public boolean isValidDouble(String value) {
    return value.matches("[-+]?[0-9]*\\.?[0-9]+([eE][-+]?[0-9]+)?([fFdD]?)\n") && value.contains("E") && value.contains("-");
}

It should generate the correct values like +727498D, +0.402E-816f, +0046.827E+92629d.

Checklist:

• The change followed the style guidelines of the UTBot project
• Self-review of the code is passed
• The change contains enough commentaries, particularly in hard-to-understand areas
• New documentation is provided or existed one is altered
• No new warnings
• New tests have been added
• All tests pass locally with my changes

[dtim]

LGTM (there is a stylistic comment, but it seems to be just a matter of taste)

[dtim]

Java Comparator<T> interface (and its counterpart in the Kotlin stdlib) has reversed method that returns a comparator with reverse ordering. What do you think about using reversed() instead of reverse() here? I think it could be a bit more readable (at least it would be for me -- I used to read 'reverse()` as an in-place operation on collections).