From 38920e3be66ab95e48a4e96023853b6305b52070 Mon Sep 17 00:00:00 2001
From: dudaodong <lanliddd.2007@163.com>
Date: Mon, 29 Jan 2024 11:00:50 +0800
Subject: [PATCH] fix: fix issue #162

---
 pointer/pointer.go     | 11 +++++++++--
 structs/field.go       | 14 +++++++++++++-
 structs/struct.go      |  6 ++++++
 structs/struct_test.go | 39 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 67 insertions(+), 3 deletions(-)

diff --git a/pointer/pointer.go b/pointer/pointer.go
index 91439ed..9b630ef 100644
--- a/pointer/pointer.go
+++ b/pointer/pointer.go
@@ -4,7 +4,9 @@
 // Package pointer contains some util functions to operate go pointer.
 package pointer
 
-import "reflect"
+import (
+	"reflect"
+)
 
 // Of returns a pointer to the value `v`.
 // Play: https://go.dev/play/p/HFd70x4DrMj
@@ -47,5 +49,10 @@ func ExtractPointer(value any) any {
 	if t.Kind() != reflect.Pointer {
 		return value
 	}
-	return ExtractPointer(v.Elem().Interface())
+
+	if v.Elem().IsValid() {
+		return ExtractPointer(v.Elem().Interface())
+	}
+
+	return nil
 }
diff --git a/structs/field.go b/structs/field.go
index 5815b12..cff2f43 100644
--- a/structs/field.go
+++ b/structs/field.go
@@ -52,6 +52,16 @@ func (f *Field) IsZero() bool {
 	return reflect.DeepEqual(z, v)
 }
 
+// IsNil returns true if the given field is nil value.
+func (f *Field) IsNil() bool {
+	v := f.Value()
+	if v == nil || (reflect.ValueOf(v)).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil() {
+		return true
+	}
+
+	return false
+}
+
 // Name returns the name of the given field
 func (f *Field) Name() string {
 	return f.field.Name
@@ -111,7 +121,9 @@ func (f *Field) mapValue(value any) any {
 			ret = v.Interface()
 		}
 	default:
-		ret = v.Interface()
+		if v.Kind().String() != "invalid" {
+			ret = v.Interface()
+		}
 	}
 	return ret
 }
diff --git a/structs/struct.go b/structs/struct.go
index 14207ed..ed73202 100644
--- a/structs/struct.go
+++ b/structs/struct.go
@@ -71,9 +71,15 @@ func (s *Struct) ToMap() (map[string]any, error) {
 		if !f.IsExported() || f.tag.IsEmpty() || f.tag.Name == "-" {
 			continue
 		}
+
 		if f.IsZero() && f.tag.HasOption("omitempty") {
 			continue
 		}
+
+		if f.IsNil() {
+			continue
+		}
+
 		result[f.tag.Name] = f.mapValue(f.Value())
 	}
 
diff --git a/structs/struct_test.go b/structs/struct_test.go
index 25ffe2c..8040ced 100644
--- a/structs/struct_test.go
+++ b/structs/struct_test.go
@@ -65,6 +65,45 @@ func TestStruct_ToMap(t *testing.T) {
 	})
 }
 
+func Test_ToMap2(t *testing.T) {
+	t.Parallel()
+	assert := internal.NewAssert(t, "TestStruct_ToMap")
+
+	type M struct {
+		Name string `json:"name"`
+	}
+
+	type S struct {
+		ID int `json:"id"`
+		M  *M  `json:"m"`
+	}
+
+	s1 := &S{
+		ID: 1,
+	}
+	var expect1 = map[string]any{"id": 1}
+	map1, err := ToMap(s1)
+
+	assert.IsNil(err)
+	assert.Equal(expect1, map1)
+
+	s2 := &S{
+		ID: 1,
+		M: &M{
+			Name: "test",
+		},
+	}
+	var expect2 = map[string]any{
+		"id": 1,
+		"m": map[string]any{
+			"name": "test",
+		}}
+	map2, err := ToMap(s2)
+
+	assert.IsNil(err)
+	assert.Equal(expect2, map2)
+}
+
 func TestStruct_Fields(t *testing.T) {
 	t.Parallel()