refactor ReplaceFrom()

node/edit.go

@@ -16,6 +16,7 @@ const (
 	editUpsert editStrategy = iota + 1
 	editInsert
 	editUpdate
+	editReplace
 )
 
 type editor struct {
@@ -51,7 +52,6 @@ func (e editor) enter(from *Selection, to *Selection, new bool, strategy editStr
 	} else {
 		ml := newContainerMetaList(from)
 		m := ml.nextMeta()
-		//fmt.Printf("Begin %s\n", meta.SchemaPath(from.Meta()))
 		for m != nil {
 			var err error
 			if meta.IsLeaf(m) {
@@ -64,7 +64,6 @@ func (e editor) enter(from *Selection, to *Selection, new bool, strategy editStr
 			}
 			m = ml.nextMeta()
 		}
-		//fmt.Printf("Ended %s\n", meta.SchemaPath(from.Meta()))
 	}
 	return nil
 }
@@ -84,19 +83,24 @@ func (e editor) leaf(from *Selection, to *Selection, m meta.Leafable, new bool,
 		return err
 	}
 
+	r.Selection = to
+	r.From = from
 	if hnd.Val != nil {
 		// If there is a different choice selected, need to clear it
 		// first if in upsert mode
-		if strategy == editUpsert {
+		if strategy == editUpsert || strategy == editReplace {
 			if err := e.clearOnDifferentChoiceCase(to, m); err != nil {
 				return err
 			}
 		}
-		r.Selection = to
-		r.From = from
 		if err := to.set(&r, &hnd); err != nil {
 			return err
 		}
+	} else if strategy == editReplace {
+		r.Clear = true
+		if err := to.set(&r, &ValueHandle{}); err != nil {
+			return err
+		}
 	}
 	return nil
 }
@@ -147,6 +151,24 @@ func (e editor) clearChoiceCase(sel *Selection, c *meta.ChoiceCase) error {
 func (e editor) node(from *Selection, to *Selection, m meta.HasDataDefinitions, new bool, strategy editStrategy) error {
 	var newChild bool
 	var err error
+	// this ensures that even on panic we release any selections created in this func and it's loop
+	var fromChild *Selection
+	var toChild *Selection
+	releaseFromChild := func() {
+		if fromChild != nil {
+			fromChild.Release()
+			fromChild = nil
+		}
+	}
+	defer releaseFromChild()
+	releaseToChild := func() {
+		if toChild != nil {
+			toChild.Release()
+			toChild = nil
+		}
+	}
+	defer releaseToChild()
+
 	fromRequest := ChildRequest{
 		Request: Request{
 			Selection: from,
@@ -155,11 +177,13 @@ func (e editor) node(from *Selection, to *Selection, m meta.HasDataDefinitions,
 		},
 		Meta: m,
 	}
-	fromChild, err := from.selekt(&fromRequest)
-	if fromChild == nil || err != nil {
+	fromChild, err = from.selekt(&fromRequest)
+	if err != nil {
 		return err
 	}
-	defer fromChild.Release()
+	if fromChild == nil && strategy != editReplace {
+		return nil
+	}
 	toRequest := ChildRequest{
 		Request: Request{
 			Selection: to,
@@ -171,23 +195,34 @@ func (e editor) node(from *Selection, to *Selection, m meta.HasDataDefinitions,
 	toRequest.New = false
 	toRequest.Selection = to
 
-	toChild, err := to.selekt(&toRequest)
+	toChild, err = to.selekt(&toRequest)
 	if err != nil {
 		return err
 	}
-	if toChild != nil {
-		defer toChild.Release()
-	}
-	toRequest.New = true
+
 	switch strategy {
 	case editInsert:
 		if toChild != nil {
 			return fmt.Errorf("%w. item '%s' found in '%s'.  ", fc.ConflictError, m.Ident(), fromRequest.Path)
 		}
+		toRequest.New = true
+		if toChild, err = to.selekt(&toRequest); err != nil {
+			return err
+		}
+		newChild = true
+	case editReplace:
+		if toChild != nil {
+			if err := toChild.delete(); err != nil {
+				return err
+			}
+		}
+		if fromChild == nil {
+			return nil
+		}
+		toRequest.New = true
 		if toChild, err = to.selekt(&toRequest); err != nil {
 			return err
 		}
-		defer toChild.Release()
 		newChild = true
 	case editUpsert:
 
@@ -198,12 +233,10 @@ func (e editor) node(from *Selection, to *Selection, m meta.HasDataDefinitions,
 		}
 
 		if toChild == nil {
+			toRequest.New = true
 			if toChild, err = to.selekt(&toRequest); err != nil {
 				return err
 			}
-			if toChild != nil {
-				defer toChild.Release()
-			}
 			newChild = true
 		}
 	case editUpdate:
@@ -225,7 +258,6 @@ func (e editor) node(from *Selection, to *Selection, m meta.HasDataDefinitions,
 }
 
 func (e editor) list(from *Selection, to *Selection, m *meta.List, new bool, strategy editStrategy) error {
-
 	// this ensures that even on panic we release any selections created in this func and it's loop
 	var fromChild *Selection
 	var toChild *Selection
@@ -257,7 +289,7 @@ func (e editor) list(from *Selection, to *Selection, m *meta.List, new bool, str
 	var key []val.Value
 	var err error
 	fromChild, key, err = from.selectVisibleListItem(fromRequest)
-	if err != nil || fromChild == nil {
+	if err != nil {
 		return err
 	}
 	p.Key = key
@@ -310,6 +342,11 @@ func (e editor) list(from *Selection, to *Selection, m *meta.List, new bool, str
 				return err
 			}
 			newItem = true
+		case editReplace:
+			if toChild, _, _, err = to.selectListItem(&toRequest); err != nil {
+				return err
+			}
+			newItem = true
 		default:
 			return strategyNotImplemented
 		}
@@ -330,5 +367,57 @@ func (e editor) list(from *Selection, to *Selection, m *meta.List, new bool, str
 			return err
 		}
 	}
+	if strategy == editReplace {
+		// Iterate through "to" list, look if such element is in "from" list, delete otherwise
+		p = *to.Path
+		toRequest = ListRequest{
+			Request: Request{
+				Selection: to,
+				Path:      &p,
+				Base:      e.basePath,
+			},
+			First: true,
+			Meta:  m,
+		}
+		fromRequest = &ListRequest{
+			Request: Request{
+				Selection: from,
+				Path:      &p,
+				Base:      e.basePath,
+			},
+			First: true,
+			Meta:  m,
+		}
+		for {
+			if toChild, _, key, err = to.selectListItem(&toRequest); err != nil {
+				return err
+			}
+			if toChild == nil {
+				break
+			}
+
+			fromRequest.First = true
+			fromRequest.SetRow(toRequest.Row64)
+			fromRequest.Selection = to
+			fromRequest.From = toChild
+			fromRequest.Key = key
+			p.Key = key
+			if fromChild, _, _, err = from.selectListItem(fromRequest); err != nil {
+				return err
+			}
+			if fromChild == nil {
+				fmt.Printf("|||||delete fromChild=%v\n", toChild.Path)
+				if err = toChild.delete(); err != nil {
+					return err
+				}
+				toChild = nil
+			}
+
+			releaseToChild()
+			releaseFromChild()
+
+			toRequest.IncrementRow()
+		}
+	}
 	return nil
 }

node/selection.go

@@ -385,6 +385,11 @@ func (sel *Selection) Delete() (err error) {
 		}
 	}()
 
+	err = sel.delete()
+	return
+}
+
+func (sel *Selection) delete() (err error) {
 	if sel.InsideList {
 		r := ListRequest{
 			Request: Request{
@@ -468,12 +473,10 @@ func (sel *Selection) UpdateInto(toNode Node) error {
 	return e.edit(sel, sel.Split(toNode), editUpdate)
 }
 
+// Replace current tree with given one
 func (sel *Selection) ReplaceFrom(fromNode Node) error {
-	parent := sel.parent
-	if err := sel.Delete(); err != nil {
-		return err
-	}
-	return parent.InsertFrom(fromNode)
+	e := editor{basePath: sel.Path}
+	return e.edit(sel.Split(fromNode), sel, editReplace)
 }
 
 // Copy given node into current node.  There must be matching containers of list

node/selection_test.go

@@ -84,25 +84,35 @@ func TestReplaceFrom(t *testing.T) {
 	sel, err := root.Find("bird=robin/species")
 	fc.RequireEqual(t, nil, err)
 	n, _ := nodeutil.ReadJSON(`
-		{"species":{"name":"dragon"}}
+		{"class":"dragon"}
 	`)
 	err = sel.ReplaceFrom(n)
 	fc.AssertEqual(t, nil, err)
 	sel, err = root.Find("bird=robin")
 	fc.RequireEqual(t, nil, err)
 	actual, err := js.JSON(sel)
 	fc.AssertEqual(t, nil, err)
-	fc.AssertEqual(t, `{"name":"robin","wingspan":10,"species":{"name":"dragon"}}`, actual)
+	fc.AssertEqual(t, `{"name":"robin","wingspan":10,"species":{"class":"dragon"}}`, actual)
 
 	// list item
 	sel, err = root.Find("bird=robin")
 	fc.RequireEqual(t, nil, err)
 	n, _ = nodeutil.ReadJSON(`
-		{"bird":[{"name": "robin", "wingspan":11}]}
+		{"name": "robin", "wingspan":11}
 	`)
 	sel.ReplaceFrom(n)
 	fc.AssertEqual(t, nil, err)
 	actual, err = js.JSON(root)
 	fc.AssertEqual(t, nil, err)
 	fc.AssertEqual(t, `{"bird":[{"name":"blue jay","wingspan":0},{"name":"robin","wingspan":11}]}`, actual)
+
+	// whole list
+	n, _ = nodeutil.ReadJSON(`
+		{"bird":[{"name":"blue jay"},{"name":"malak","species":{"class":"jedi"}}]}
+	`)
+	root.ReplaceFrom(n)
+	fc.AssertEqual(t, nil, err)
+	actual, err = js.JSON(root)
+	fc.AssertEqual(t, nil, err)
+	fc.AssertEqual(t, `{"bird":[{"name":"blue jay","wingspan":0},{"name":"malak","wingspan":0,"species":{"class":"jedi"}}]}`, actual)
 }