preview.go

// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package e2e

import (
	"fmt"
	"os"
	"strings"
	"testing"

	"google.golang.org/grpc"

	"go.ate.dev/substrate/internal/preview"

	"github.com/spf13/pflag"
)

// previewFlag lists the preview gates the install under test enabled, in the
// same syntax as ate-setup's ATE_PREVIEW: comma- or space-separated gate
// names, or "ALL" for all of them. Empty means none.
var previewFlag string

// previewRequired reports whether --preview must be passed. A lane that
// forgets it would otherwise skip every preview test and still pass, so CI
// must declare its preview mode, even if only as empty.
func previewRequired() bool {
	return os.Getenv("CI") == "true"
}

// previewGates returns the gates in value. set reports whether --preview was
// passed at all.
func previewGates(value string, set bool) ([]string, error) {
	if !set && previewRequired() {
		return nil, fmt.Errorf("--preview must be passed in CI (empty for no preview gates)")
	}
	return strings.FieldsFunc(value, func(r rune) bool {
		return r == ',' || r == ' ' || r == '\t' || r == '\n'
	}), nil
}

// initPreview sets the process-wide preview gates from --preview.
func initPreview() error {
	gates, err := previewGates(previewFlag, pflag.CommandLine.Changed("preview"))
	if err != nil {
		return err
	}
	if err := preview.Init(gates...); err != nil {
		return fmt.Errorf("--preview: %w", err)
	}
	return nil
}

// previewDialOptions returns the options for the ATE API client to opt in to
// preview features, if the install under test enabled any.
func previewDialOptions() []grpc.DialOption {
	for _, enabled := range preview.AsMap() {
		if enabled {
			return preview.DialOptionsWithOptIn()
		}
	}
	return nil
}

// RequirePreview skips t unless the install under test enabled gate. Tests of
// a preview feature call it first, so a run without the gate skips them.
func RequirePreview(t testing.TB, gate preview.Gate) {
	t.Helper()
	if !preview.IsEnabled(gate) {
		t.Skipf("preview gate %q is not enabled (pass --preview)", gate)
	}
}