[NEP25] - Validate circular reference

[ajara87]

Description

• Add circular reference detection for namedtypes in ContractAbi. This validation needs global visibility of all namedtype relations, so it is implemented at the ABI level.
• Tests coverage for circular references:
• • A => A. Invalid
• • A => B, B => A. Invalid
• • A => B => C => A. Invalid
• • A => B => C => B. Invalid
• • A => value, B => A, C => A. Valid
• • A => value, value => A. Valid
• • A => value, value => B | B => value, value => A. Valid
• • A => B => C. Valid

Type of change

• Optimization (the change is only an optimization)
• Style (the change is only a code style for better maintenance or standard purpose)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• FromJson_Circular_Reference_A_A_ShouldThrow
• FromJson_Circular_Reference_A_B_B_A_ShouldThrow
• FromJson_Circular_Reference_A_B_C_A_ShouldThrow
• FromJson_Circular_Reference_A_B_C_B_ShouldThrow
• FromJson_No_Circular_Reference_A_B_C
• FromJson_Circular_Reference_A_NO_B_A_C_A
• FromJson_Circular_Reference_A_VALUE_A
• FromJson_Circular_Reference_A_VALUE_B_B_VALUE_A

Test Configuration:

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[shargon]

Could you add a test for
A
B-> A
C-> A

[ajara87]

Could you add a test for A B-> A C-> A

added