isle/go/cmd/entrypoint/main_test.go

package main

import (
	"bytes"
	"context"
	"isle/daemon"
	"isle/daemon/jsonrpc2"
	"isle/toolkit"
	"net/http/httptest"
	"reflect"
	"testing"

	"dev.mediocregopher.com/mediocre-go-lib.git/mlog"
	"github.com/stretchr/testify/assert"
	"gopkg.in/yaml.v3"
)

type runHarness struct {
	ctx             context.Context
	logger          *mlog.Logger
	stdout          *bytes.Buffer
	daemonRPC       *daemon.MockRPC
	daemonRPCServer *httptest.Server
}

func newRunHarness(t *testing.T) *runHarness {
	t.Parallel()

	var (
		ctx    = context.Background()
		logger = toolkit.NewTestLogger(t)
		stdout = new(bytes.Buffer)

		daemonRPC        = daemon.NewMockRPC(t)
		daemonRPCHandler = jsonrpc2.NewHTTPHandler(daemon.NewRPCHandler(
			logger.WithNamespace("rpc"), daemonRPC,
		))
		daemonRPCServer = httptest.NewServer(daemonRPCHandler)
	)

	t.Cleanup(daemonRPCServer.Close)

	return &runHarness{ctx, logger, stdout, daemonRPC, daemonRPCServer}
}

func (h *runHarness) run(t *testing.T, args ...string) error {
	httpClient := toolkit.NewHTTPClient(h.logger.WithNamespace("http"))
	t.Cleanup(func() {
		assert.NoError(t, httpClient.Close())
	})

	daemonRPCClient := daemon.RPCFromClient(
		jsonrpc2.NewHTTPClient(httpClient, h.daemonRPCServer.URL),
	)

	return doRootCmd(h.ctx, h.logger, &subCmdCtxOpts{
		args:      args,
		daemonRPC: daemonRPCClient,
		stdout:    h.stdout,
	})
}

func (h *runHarness) runAssertStdout(
	t *testing.T,
	want any,
	args ...string,
) {
	var (
		gotType = reflect.ValueOf(want)
		got     = reflect.New(gotType.Type())
	)

	h.stdout.Reset()
	assert.NoError(t, h.run(t, args...))
	assert.NoError(t, yaml.Unmarshal(h.stdout.Bytes(), got.Interface()))
	assert.Equal(t, want, got.Elem().Interface())
}