mediocre-go-lib/mtest/mtest.go

66 lines
1.8 KiB
Go
Raw Normal View History

// Package mtest implements functionality useful for testing.
package mtest
import (
"context"
"testing"
"github.com/mediocregopher/mediocre-go-lib/mcfg"
"github.com/mediocregopher/mediocre-go-lib/mlog"
"github.com/mediocregopher/mediocre-go-lib/mrun"
)
type envCtxKey int
// Context creates and returns a root Context suitable for testing.
func Context() context.Context {
ctx := context.Background()
logger := mlog.NewLogger()
logger.SetMaxLevel(mlog.DebugLevel)
return mlog.WithLogger(ctx, logger)
}
// WithEnv sets the given environment variable on the given Context, such that
// it will be used as if it was a real environment variable when the Run
// function from this package is called.
func WithEnv(ctx context.Context, key, val string) context.Context {
prevEnv, _ := ctx.Value(envCtxKey(0)).([][2]string)
env := make([][2]string, len(prevEnv), len(prevEnv)+1)
copy(env, prevEnv)
env = append(env, [2]string{key, val})
return context.WithValue(ctx, envCtxKey(0), env)
}
// Run performs the following using the given Context:
//
// - Calls mcfg.Populate using any variables set by WithEnv.
//
// - Calls mrun.Start
//
// - Calls the passed in body callback.
//
// - Calls mrun.Stop
//
// The intention is that Run is used within a test on a Context created via
// NewCtx, after any setup functions have been called (e.g. mnet.WithListener).
func Run(ctx context.Context, t *testing.T, body func()) {
envTups, _ := ctx.Value(envCtxKey(0)).([][2]string)
env := make([]string, 0, len(envTups))
for _, tup := range envTups {
env = append(env, tup[0]+"="+tup[1])
}
2019-04-04 18:21:44 +00:00
ctx, err := mcfg.Populate(ctx, &mcfg.SourceEnv{Env: env})
if err != nil {
t.Fatal(err)
} else if err := mrun.Start(ctx); err != nil {
t.Fatal(err)
}
body()
if err := mrun.Stop(ctx); err != nil {
t.Fatal(err)
}
}