diff --git a/zap/filter_core_test.go b/zap/filter_core_test.go
index ea3a574a392f33051b8cca4920aa8b036a63bbe2..01e4694f9b04c1a7eca79ff12cb662a614c56320 100644
--- a/zap/filter_core_test.go
+++ b/zap/filter_core_test.go
@@ -13,12 +13,14 @@ func TestFilterCore_With(t *testing.T) {
 	core, logs := observer.New(zapcore.InfoLevel)
 	core = WithFilters(core)
 
-	err := core.With([]zapcore.Field{zap.String("k", "v")}).Write(zapcore.Entry{Message: "msg"}, nil)
+	field := zap.String("k", "v")
+	err := core.With([]zapcore.Field{field}).Write(zapcore.Entry{Message: "msg"}, nil)
 	require.NoError(t, err)
 
 	entries := logs.All()
 	require.Len(t, entries, 1)
 	require.Len(t, entries[0].Context, 1)
+	require.True(t, field.Equals(entries[0].Context[0]))
 }
 
 func TestFilterCore_Write(t *testing.T) {