orderdmap: add json tests

Author: alessio-perugini

internal/orderedmap/orderedmap.go

@@ -18,6 +18,7 @@ package orderedmap
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"slices"
 )
 
@@ -38,10 +39,15 @@ type Map[K any, V any] interface {
 	MarshalJSON() ([]byte, error)
 }
 
+type scalars interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64 | ~uint | ~uint8 |
+		~uint16 | ~uint32 | ~uint64 | ~uintptr | ~float32 | ~float64 | ~string
+}
+
 // NewWithConversionFunc creates a map using the given conversion function
 // to convert non-comparable key type to comparable items.
 // The conversion function must be bijective.
-func NewWithConversionFunc[K any, V any, C comparable](conv func(K) C) Map[K, V] {
+func NewWithConversionFunc[K any, V any, C scalars](conv func(K) C) Map[K, V] {
 	return &mapImpl[K, V, C]{
 		conv: conv,
 		kv:   map[C]V{},
@@ -50,15 +56,15 @@ func NewWithConversionFunc[K any, V any, C comparable](conv func(K) C) Map[K, V]
 }
 
 // New creates a map
-func New[K comparable, V any]() Map[K, V] {
+func New[K scalars, V any]() Map[K, V] {
 	return &mapImpl[K, V, K]{
 		conv: func(in K) K { return in }, // identity
 		kv:   map[K]V{},
 		o:    []K{},
 	}
 }
 
-type mapImpl[K any, V any, C comparable] struct {
+type mapImpl[K any, V any, C scalars] struct {
 	conv func(K) C
 	kv   map[C]V
 	o    []K
@@ -91,7 +97,8 @@ func (m *mapImpl[K, V, C]) MarshalJSON() ([]byte, error) {
 	buf.WriteByte('{')
 	encoder := json.NewEncoder(&buf)
 	for _, k := range m.o {
-		if err := encoder.Encode(k); err != nil {
+		// Here we convert non string keys in string.
+		if err := encoder.Encode(fmt.Sprintf("%v", m.conv(k))); err != nil {
 			return nil, err
 		}
 		buf.WriteByte(':')

internal/orderedmap/orderedmap_test.go

@@ -67,36 +67,6 @@ func TestGet(t *testing.T) {
 		require.True(t, ok)
 	})
 
-	t.Run("the key is a pointer", func(t *testing.T) {
-		m := orderedmap.New[*string, int]()
-
-		notExistingKey := toPtr("not-existing-key")
-		require.Equal(t, 0, m.Get(notExistingKey))
-		v, ok := m.GetOk(notExistingKey)
-		require.Zero(t, v)
-		require.False(t, ok)
-
-		existingKey := toPtr("existing-key")
-		m.Set(existingKey, 1)
-		require.Equal(t, 1, m.Get(existingKey))
-		v, ok = m.GetOk(existingKey)
-		require.Equal(t, 1, v)
-		require.True(t, ok)
-
-		// Using a different pointer with the same value returns no result
-		require.Equal(t, 0, m.Get(toPtr("existing-key")))
-		v, ok = m.GetOk(toPtr("existing-key"))
-		require.Zero(t, v)
-		require.False(t, ok)
-
-		// test empty key
-		m.Set(nil, 2)
-		require.Equal(t, 2, m.Get(nil))
-		v, ok = m.GetOk(nil)
-		require.Equal(t, 2, v)
-		require.True(t, ok)
-	})
-
 	t.Run("custom comparable key", func(t *testing.T) {
 		type A struct {
 			b []byte
@@ -345,6 +315,47 @@ func TestClone(t *testing.T) {
 	})
 }
 
+func TestMarshallJSON(t *testing.T) {
+	t.Run("empty map", func(t *testing.T) {
+		m := orderedmap.New[string, int]()
+		mapJSON, err := m.MarshalJSON()
+		require.NoError(t, err)
+		require.JSONEq(t, `{}`, string(mapJSON))
+	})
+	t.Run("respect the order of insertion", func(t *testing.T) {
+		m := orderedmap.New[string, int]()
+		m.Set("a", 1)
+		m.Set("b", 2)
+		m.Set("c", 3)
+		mapJSON, err := m.MarshalJSON()
+		require.NoError(t, err)
+		require.JSONEq(t, `{"a":1,"b":2,"c":3}`, string(mapJSON))
+	})
+	t.Run("can serialize int keys", func(t *testing.T) {
+		m := orderedmap.New[int, bool]()
+		m.Set(1, true)
+		m.Set(2, true)
+		m.Set(3, true)
+		mapJSON, err := m.MarshalJSON()
+		require.NoError(t, err)
+		require.JSONEq(t, `{"1":true,"2":true,"3":true}`, string(mapJSON))
+	})
+	t.Run("can serialize pointer keys", func(t *testing.T) {
+		m := orderedmap.NewWithConversionFunc[*int, bool, int](func(i *int) int {
+			if i == nil {
+				return 0
+			}
+			return *i
+		})
+		m.Set(toPtr(1), true)
+		m.Set(toPtr(2), true)
+		m.Set(toPtr(3), true)
+		mapJSON, err := m.MarshalJSON()
+		require.NoError(t, err)
+		require.JSONEq(t, `{"1":true,"2":true,"3":true}`, string(mapJSON))
+	})
+}
+
 func toPtr[V any](v V) *V {
 	return &v
 }