x

core/conf/config.go

@@ -32,7 +32,8 @@ type fieldInfo struct {
 	mapField *fieldInfo
 }
 
-// FillDefault fills the default values for the given v.
+// FillDefault fills the default values for the given v,
+// and the premise is that the value of v must be guaranteed to be empty
 func FillDefault(v any) error {
 	return fillDefaultUnmarshaler.Unmarshal(map[string]any{}, v)
 }

core/conf/config_test.go

@@ -1078,4 +1078,16 @@ func TestFillDefaultUnmarshal(t *testing.T) {
 		assert.Equal(t, st.A, "a")
 		assert.Equal(t, st.C, "c")
 	})
+
+	t.Run("has vaue", func(t *testing.T) {
+		type St struct {
+			A string `json:",default=a"`
+			B string
+		}
+		var st = St{
+			A: "b",
+		}
+		err := FillDefault(&st)
+		assert.Error(t, err)
+	})
 }