Pretty-print driver.Valuer

Author: ammario

internal/entryhuman/entry.go

@@ -4,6 +4,7 @@ package entryhuman
 
 import (
 	"bytes"
+	"database/sql/driver"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -56,6 +57,13 @@ func reset(w io.Writer, termW io.Writer) {
 }
 
 func formatValue(v interface{}) string {
+	if vr, ok := v.(driver.Valuer); ok {
+		var err error
+		v, err = vr.Value()
+		if err != nil {
+			return fmt.Sprintf("error calling Value: %v", err)
+		}
+	}
 	if v == nil {
 		return "<nil>"
 	}

internal/entryhuman/entry_test.go

@@ -2,6 +2,7 @@ package entryhuman_test
 
 import (
 	"bytes"
+	"database/sql"
 	"flag"
 	"fmt"
 	"io"
@@ -108,6 +109,16 @@ func TestEntry(t *testing.T) {
 				),
 			},
 		},
+		{
+			"driverValue",
+			slog.SinkEntry{
+				Level: slog.LevelWarn,
+				Fields: slog.M(
+					slog.F("val", sql.NullString{String: "dog", Valid: true}),
+					slog.F("inval", sql.NullString{String: "cat", Valid: false}),
+				),
+			},
+		},
 		{
 			"object",
 			slog.SinkEntry{

internal/entryhuman/testdata/driverValue.golden

@@ -0,0 +1 @@
+0001-01-01 00:00:00.000 [warn]    val=dog  inval=<nil>