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slog ​

Test-friendly slog.Handler that writes log output through testing.TB.

Import ​

go
import goslog "github.com/foomo/go/slog"

API ​

NewTestHandler ​

go
func NewTestHandler(tb testing.TB, opts ...TestHandlerOption) slog.Handler

Returns an slog.Handler that writes log records to tb.Output in a compact format:

file.go:42: [LEVEL] msg key=value ...

Defaults to slog.LevelDebug. Supports WithAttrs and WithGroup for structured context.

TestHandlerWithLevel ​

go
func TestHandlerWithLevel(level slog.Leveler) TestHandlerOption

Sets the minimum log level for the test handler.

Example ​

go
func TestService(t *testing.T) {
	logger := slog.New(goslog.NewTestHandler(t))
	logger.Info("starting", "port", 8080)
	// Output via t.Log: testfile_test.go:4: [INFO] starting port=8080
}

With minimum level ​

go
func TestServiceWarn(t *testing.T) {
	logger := slog.New(goslog.NewTestHandler(t, goslog.TestHandlerWithLevel(slog.LevelWarn)))
	logger.Debug("ignored") // not printed
	logger.Warn("something happened", "err", "timeout")
}