add platformtest: infrastructure for ZFS compatiblity testing

platformtest/platformtest_logging.go

@@ -0,0 +1,24 @@
+package platformtest
+
+import (
+	"context"
+
+	"github.com/zrepl/zrepl/logger"
+)
+
+type Logger = logger.Logger
+
+type contextKey int
+
+const (
+	contextKeyLogger contextKey = iota
+)
+
+func WithLogger(ctx context.Context, logger Logger) context.Context {
+	ctx = context.WithValue(ctx, contextKeyLogger, logger)
+	return ctx
+}
+
+func getLog(ctx context.Context) Logger {
+	return ctx.Value(contextKeyLogger).(Logger)
+}