We need a testing framework for transformers

[kajogo777]

Proposal

Test case schema

#TestCase: {
	name:        string
	description: string

	transformer: #Transformer
	input:       #Component
	result:      input & transformer

	expect: result
	assert: [string]: true
}

Example test case

package main

import (
	"guku.io/devx/v1"
	"guku.io/devx/v1/traits"
	"guku.io/devx/v1/transformers/compose"
)

_t1: v1.#TestCase & {
	name:        "exposable"
	description: ""

	transformer: compose.#ExposeComposeService
	input: {
		traits.#Exposable
		$metadata: id: "obi"
		endpoints: default: ports: [
			{
				port:   8080
				target: 80
			},
		]
	}
	result: _

	expect: {
		endpoints: default: host: "obi"
		$resources: compose: services: obi: ports: ["8080:80"]
	}
	assert: {
		"host is concrete": (result.endpoints.default.host & "123") == _|_
	}
}

Run test

cue eval

[kajogo777]

added simple test case schema for transformers in 326f0fe