envgen

internal/gen/envgen

Code generator that walks k8s.io/client-go/kubernetes.Interface and emits typed resource getters on *env.Env plus a type-switching AssertPartial/AssertNone dispatcher.

What it produces

For every resource discovered through the clientset (e.g. AppsV1Interface.Deployments(ns).Get(...)) the generator emits:

// GetDeployment fetches a Deployment by name, failing the test on error.
func (env *Env) GetDeployment(t *testing.T, name string) *appsv1.Deployment { ... }

// GetDeploymentE fetches a Deployment by name, returning the error for
// non-existence checks.
func (env *Env) GetDeploymentE(t *testing.T, name string) (*appsv1.Deployment, error) { ... }

Plus a single dispatcher pair:

func (env *Env) AssertPartial(t *testing.T, name string, asn assert.Assertable) {
	switch a := asn.(type) {
	case assert.DeploymentAssertion:
		assert.Partial(t, env.GetDeployment(t, name), a, name)
	case *assert.DeploymentAssertion:
		assert.Partial(t, env.GetDeployment(t, name), *a, name)
	// ... 75+ more cases ...
	default:
		t.Fatalf("env.AssertPartial: no resource registered for assertion type %T", asn)
	}
}

func (env *Env) AssertNone(t *testing.T, name string, asn assert.Assertable) { ... }

Only resources whose Go type lives in one of the assertgen scan packages get dispatched — the rest are fetch-only.

Invocation

go run github.com/mridang/wilhelm/internal/gen/envgen \
  -out zz_generated.go \
  -package env

Wired through env/doc.go:

//go:generate go run ../internal/gen/envgen -out zz_generated.go -package env

Name disambiguation

The same Go type name (e.g. HorizontalPodAutoscaler) can be reached via multiple API group versions (v1, v2, v1beta1). Method names must be unique, so the generator scores each candidate and keeps the highest-priority one at the short name (GetHorizontalPodAutoscaler). The rest get prefixed with the group method name (e.g. GetAutoscalingV1Beta1HorizontalPodAutoscaler).

Priority order:

1. Has an assertion struct (+1000)
2. Stable > beta > alpha (+200 / +100 / +0)
3. Higher version number wins ties (e.g. v2 > v1)

Determinism

Resources are sorted by (GroupMethod, Name) before rendering. Two runs of go generate in a clean checkout produce byte-identical output.

What it does not do

• No CRD support yet. The current generator only knows about resources exposed through kubernetes.Interface. CRD subpackages will get a dynamic-client-based getter generator (planned).