Description

This PR resolves several issues:

• This instance now created with any public constructor. Reflection is used only if there's no another ways to createthis instance
• ModelProvider changed its signature to provide a sequence. This is needed to supply values lazily (for example, generate first 10 values and take random)
• For methods without parameters fuzzer will generate models to changethis instance
• No more fallback for a regular value generating. Thus, fuzzer doesn't generate test using reflection anymore (except case withthis instance)

Fixes#511

Type of Change

• Breaking change (fix or feature that would cause existing functionality to not work as expected)

How Has This Been Tested?

Automated Testing

org.utbot.framework.plugin.api.ModelProviderTest

Manual Scenario

Test methodfoo from this example:

packagecom.company.objects;publicclassTestThisInstance {MyObjectvalue;TestThisInstance() {}TestThisInstance(intvalue) {this.value =newMyObject();this.value.setField(value);    }publicbooleanfoo() {if (value.getField() <100 ||value.getField() ==102) {returntrue;        }returnvalue.getField() %2 ==0;    }}classMyObject {privateintfield;publicintgetField() {returnfield;    }publicvoidsetField(intfield) {this.field =field;    }}

Checklist (remove irrelevant options):

• 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
• All tests pass locally with my changes