Adds log sink that uses the standard logger

tfsdklog/sink.go

@@ -7,6 +7,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"log"
 	"os"
 	"strings"
 	"sync"
@@ -153,3 +154,30 @@ func isValidLogLevel(level string) bool {
 
 	return false
 }
+
+// RegisterStdlogSink sets up a logging sink for use with test sweepers and
+// other cases where plugin logs don't get routed through Terraform and the
+// built-in Go `log` package is also used.
+//
+// RegisterStdlogSink should only ever be called by test sweepers, providers
+// should never call it.
+//
+// RegisterStdlogSink must be called prior to any loggers being setup or
+// instantiated.
+func RegisterStdlogSink(ctx context.Context) context.Context {
+	logger, loggerOptions := newStdlogSink()
+
+	ctx = logging.SetSink(ctx, logger)
+	ctx = logging.SetSinkOptions(ctx, loggerOptions)
+
+	return ctx
+}
+
+func newStdlogSink() (hclog.Logger, *hclog.LoggerOptions) {
+	loggerOptions := &hclog.LoggerOptions{
+		IndependentLevels: true,
+		JSONFormat:        false,
+	}
+
+	return hclog.FromStandardLogger(log.Default(), loggerOptions), loggerOptions
+}