Add simple update test

data/document.go

@@ -28,7 +28,7 @@ type Document struct {
 type UpdateResult int
 
 const (
-	UpdateResultNoAction = iota
+	UpdateResultNoAction UpdateResult = iota
 	UpdateResultAppend
 	UpdateResultRebuild
 )
@@ -56,6 +56,7 @@ func NewDocument(
 func (d *Document) Update(changes ...*threadmodels.RawChange) (DocumentState, UpdateResult, error) {
 	var treeChanges []*Change
 
+	var foundACLChange bool
 	for _, ch := range changes {
 		aclChange, err := d.treeBuilder.makeVerifiedACLChange(ch)
 		if err != nil {
@@ -71,13 +72,14 @@ func (d *Document) Update(changes ...*threadmodels.RawChange) (DocumentState, Up
 		if err != nil {
 			return nil, UpdateResultNoAction, fmt.Errorf("change with id %s cannot be added: %w", ch.Id, err)
 		}
+		if treeChange.IsACLChange() {
+			foundACLChange = true
+		}
 	}
 
-	for _, ch := range treeChanges {
-		if ch.IsACLChange() {
-			res, err := d.Build()
-			return res, UpdateResultRebuild, err
-		}
+	if foundACLChange {
+		res, err := d.Build()
+		return res, UpdateResultRebuild, err
 	}
 
 	prevHeads := d.docContext.fullTree.Heads()
@@ -92,11 +94,28 @@ func (d *Document) Update(changes ...*threadmodels.RawChange) (DocumentState, Up
 		break
 	}
 
+	// decrypting everything, because we have no new keys
+	for _, ch := range treeChanges {
+		if ch.Content.GetChangesData() != nil {
+			key, exists := d.docContext.aclState.userReadKeys[ch.Content.CurrentReadKeyHash]
+			if !exists {
+				err := fmt.Errorf("failed to find key with hash: %d", ch.Content.CurrentReadKeyHash)
+				return nil, UpdateResultNoAction, err
+			}
+
+			err := ch.DecryptContents(key)
+			if err != nil {
+				err = fmt.Errorf("failed to decrypt contents for hash: %d", ch.Content.CurrentReadKeyHash)
+				return nil, UpdateResultNoAction, err
+			}
+		}
+	}
+
 	// because for every new change we know it was after any of the previous heads
 	// each of previous heads must have same "Next" nodes
 	// so it doesn't matter which one we choose
 	// so we choose first one
-	newState, err := d.docStateBuilder.appendFrom(prevHeads[0])
+	newState, err := d.docStateBuilder.appendFrom(prevHeads[0], d.docContext.docState)
 	if err != nil {
 		res, _ := d.Build()
 		return res, UpdateResultRebuild, fmt.Errorf("could not add changes to state, rebuilded")

data/document_test.go

@@ -26,3 +26,28 @@ func TestDocument_Build(t *testing.T) {
 	st := res.(*PlainTextDocumentState)
 	assert.Equal(t, st.Text, "some text|first")
 }
+
+func TestDocument_Update(t *testing.T) {
+	thread, err := threadbuilder.NewThreadBuilderFromFile("threadbuilder/userjoinexample.yml")
+	if err != nil {
+		t.Fatal(err)
+	}
+	keychain := thread.GetKeychain()
+	accountData := &AccountData{
+		Identity: keychain.GetIdentity("A"),
+		EncKey:   keychain.EncryptionKeys["A"],
+	}
+	doc := NewDocument(thread, NewPlainTextDocumentStateProvider(), accountData)
+	res, err := doc.Build()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	st := res.(*PlainTextDocumentState)
+	assert.Equal(t, st.Text, "some text|first")
+
+	rawChs := thread.GetUpdatedChanges()
+	res, updateResult, err := doc.Update(rawChs...)
+	assert.Equal(t, updateResult, UpdateResultAppend)
+	assert.Equal(t, res.(*PlainTextDocumentState).Text, "some text|first|second")
+}

data/documentstatebuilder.go

@@ -63,8 +63,12 @@ func (d *documentStateBuilder) build() (s DocumentState, err error) {
 	return s, err
 }
 
-func (d *documentStateBuilder) appendFrom(fromId string) (s DocumentState, err error) {
+func (d *documentStateBuilder) appendFrom(fromId string, init DocumentState) (s DocumentState, err error) {
+	s = init
 	d.tree.Iterate(fromId, func(c *Change) (isContinue bool) {
+		if c.Id == fromId {
+			return true
+		}
 		if c.DecryptedDocumentChange != nil {
 			s, err = s.ApplyChange(c.DecryptedDocumentChange, c.Id)
 			if err != nil {

data/threadbuilder/userjoinexample.yml

@@ -106,7 +106,7 @@ updatedChanges:
     identity: B
     changes:
       - textAppend:
-          text: "first"
+          text: "second"
     readKey: key.Read.1
 updatedGraph:
   - id: B.1.3