test: introduces custom chai assertions

[artem-zakharchenko]

These changes introduce custom Chai assertions to use in Gavel unit and integration tests.

Motivation

• To have less verbose test suites
• To have common assertions integrated into chai chainable operators. Common assertions include:
  • result/field validity
  • expected/real type
  • errors
• To get rid of implementation details in test, and centralize validation result references (to rely on validation result structure in a single place–custom assertions declaration)
• To enhance test exceptions with more information about the scenario (include stringified validation result and optional hints)

GitHub

• Closes Consider custom chai assertions #184

Roadmap

• Implement custom assertions
  • result and field validity
  • validator
  • expectedType
  • realType
  • errors / noErrors
• Use expect instead of assert for better readability of custom assertions
• Ensured consistency of assertions between test suites
• Consider using to.not.have.validator as a replacement for .to.have.validator(null)

[artem-zakharchenko]

Experienced #139, restarting the build.

[honzajavorek]

Except the leftover commented-out code I marked with a dramatic chipmunk it is truly... beautiful!

[artem-zakharchenko]

I still would like to provide errors assertions as a part of this pull request, just to make it clear. Focusing on them now.

[honzajavorek]

I think it is completely okay to merge this now and add them in a separate PR, but up to you.

[artem-zakharchenko]

Custom assertions for the errors were also added, so the pull request should be complete!

I ditched an idea to have to.not.have.validator, because I think that conceptually means there is no validator property, which is not the expected behavior.

[honzajavorek]

🚀

[ApiaryBot]

🎉 This PR is included in version 6.1.3 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀