[#586] fixed nested multiple expands with shared path

models/record.go

@@ -132,6 +132,72 @@ func (m *Record) SetExpand(expand map[string]any) {
 	m.expand = shallowCopy(expand)
 }
 
+// MergeExpand merges recursively the provided expand data into
+// the current model's expand (if any).
+//
+// Note that if an expanded prop with the same key is a slice (old or new expand)
+// then both old and new records will be merged into a new slice (aka. a :merge: [b,c] => [a,b,c]).
+// Otherwise the "old" expanded record will be replace with the "new" one (aka. a :merge: aNew => aNew).
+func (m *Record) MergeExpand(expand map[string]any) {
+	for key, new := range expand {
+		old, ok := m.expand[key]
+		if !ok {
+			m.expand[key] = new
+			continue
+		}
+
+		var wasOldSlice bool
+		var oldSlice []*Record
+		switch v := old.(type) {
+		case *Record:
+			oldSlice = []*Record{v}
+		case []*Record:
+			wasOldSlice = true
+			oldSlice = v
+		default:
+			// invalid old expand data -> assign directly the new
+			// (no matter whether new is valid or not)
+			m.expand[key] = new
+			continue
+		}
+
+		var wasNewSlice bool
+		var newSlice []*Record
+		switch v := new.(type) {
+		case *Record:
+			newSlice = []*Record{v}
+		case []*Record:
+			wasNewSlice = true
+			newSlice = v
+		default:
+			// invalid new expand data -> skip
+			continue
+		}
+
+		oldIndexed := map[string]*Record{}
+		for _, oldRecord := range oldSlice {
+			oldIndexed[oldRecord.Id] = oldRecord
+		}
+
+		for _, newRecord := range newSlice {
+			oldRecord := oldIndexed[newRecord.Id]
+			if oldRecord != nil {
+				// note: there is no need to update oldSlice since oldRecord is a reference
+				oldRecord.MergeExpand(newRecord.Expand())
+			} else {
+				// missing new entry
+				oldSlice = append(oldSlice, newRecord)
+			}
+		}
+
+		if wasOldSlice || wasNewSlice {
+			m.expand[key] = oldSlice
+		} else {
+			m.expand[key] = oldSlice[0]
+		}
+	}
+}
+
 // SchemaData returns a shallow copy ONLY of the defined record schema fields data.
 func (m *Record) SchemaData() map[string]any {
 	result := map[string]any{}

models/record_test.go

@@ -358,7 +358,7 @@ func TestRecordOriginalCopy(t *testing.T) {
 	}
 }
 
-func TestRecordExpand(t *testing.T) {
+func TestRecordSetAndGetExpand(t *testing.T) {
 	collection := &models.Collection{}
 	m := models.NewRecord(collection)
 
@@ -375,6 +375,98 @@ func TestRecordExpand(t *testing.T) {
 	}
 }
 
+func TestRecordMergeExpandDirect(t *testing.T) {
+	collection := &models.Collection{}
+	m := models.NewRecord(collection)
+	m.Id = "m"
+
+	// a
+	a := models.NewRecord(collection)
+	a.Id = "a"
+	a1 := models.NewRecord(collection)
+	a1.Id = "a1"
+	a2 := models.NewRecord(collection)
+	a2.Id = "a2"
+	a3 := models.NewRecord(collection)
+	a3.Id = "a3"
+	a31 := models.NewRecord(collection)
+	a31.Id = "a31"
+	a32 := models.NewRecord(collection)
+	a32.Id = "a32"
+	a.SetExpand(map[string]any{
+		"a1":  a1,
+		"a23": []*models.Record{a2, a3},
+	})
+	a3.SetExpand(map[string]any{
+		"a31": a31,
+		"a32": []*models.Record{a32},
+	})
+
+	// b
+	b := models.NewRecord(collection)
+	b.Id = "b"
+	b1 := models.NewRecord(collection)
+	b1.Id = "b1"
+	b.SetExpand(map[string]any{
+		"b1": b1,
+	})
+
+	// c
+	c := models.NewRecord(collection)
+	c.Id = "c"
+
+	// load initial expand
+	m.SetExpand(map[string]any{
+		"a": a,
+		"b": b,
+		"c": []*models.Record{c},
+	})
+
+	// a (new)
+	aNew := models.NewRecord(collection)
+	aNew.Id = a.Id
+	a3New := models.NewRecord(collection)
+	a3New.Id = a3.Id
+	a32New := models.NewRecord(collection)
+	a32New.Id = "a32New"
+	a33New := models.NewRecord(collection)
+	a33New.Id = "a33New"
+	a3New.SetExpand(map[string]any{
+		"a32":    []*models.Record{a32New},
+		"a33New": a33New,
+	})
+	aNew.SetExpand(map[string]any{
+		"a23": []*models.Record{a2, a3New},
+	})
+
+	// b (new)
+	bNew := models.NewRecord(collection)
+	bNew.Id = "bNew"
+	dNew := models.NewRecord(collection)
+	dNew.Id = "dNew"
+
+	// merge expands
+	m.MergeExpand(map[string]any{
+		"a":    aNew,
+		"b":    []*models.Record{bNew},
+		"dNew": dNew,
+	})
+
+	result := m.Expand()
+
+	raw, err := json.Marshal(result)
+	if err != nil {
+		t.Fatal(err)
+	}
+	rawStr := string(raw)
+
+	expected := `{"a":{"collectionId":"","collectionName":"","created":"","expand":{"a1":{"collectionId":"","collectionName":"","created":"","id":"a1","updated":""},"a23":[{"collectionId":"","collectionName":"","created":"","id":"a2","updated":""},{"collectionId":"","collectionName":"","created":"","expand":{"a31":{"collectionId":"","collectionName":"","created":"","id":"a31","updated":""},"a32":[{"collectionId":"","collectionName":"","created":"","id":"a32","updated":""},{"collectionId":"","collectionName":"","created":"","id":"a32New","updated":""}],"a33New":{"collectionId":"","collectionName":"","created":"","id":"a33New","updated":""}},"id":"a3","updated":""}]},"id":"a","updated":""},"b":[{"collectionId":"","collectionName":"","created":"","expand":{"b1":{"collectionId":"","collectionName":"","created":"","id":"b1","updated":""}},"id":"b","updated":""},{"collectionId":"","collectionName":"","created":"","id":"bNew","updated":""}],"c":[{"collectionId":"","collectionName":"","created":"","id":"c","updated":""}],"dNew":{"collectionId":"","collectionName":"","created":"","id":"dNew","updated":""}}`
+
+	if expected != rawStr {
+		t.Fatalf("Expected \n%v, \ngot \n%v", expected, rawStr)
+	}
+}
+
 func TestRecordSchemaData(t *testing.T) {
 	collection := &models.Collection{
 		Type: models.CollectionTypeAuth,