Adding more use cases

Fleshing out design to see how it holds up, needs more work.

what-changed/external_docs.go

@@ -24,8 +24,41 @@ func (e *ExternalDocChanges) TotalChanges() int {
 
 func CompareExternalDocs(l, r *lowbase.ExternalDoc) *ExternalDocChanges {
 	var changes []*Change[*lowbase.ExternalDoc]
-	changeType := 0
+
-	if l != nil && r != nil && l.URL.Value != r.URL.Value {
+	skipURL := false
+	skipDescription := false
+
+	// check if url was removed
+	if r.URL.Value == "" && l.URL.Value != "" {
+		CreateChange[*lowbase.ExternalDoc](&changes, PropertyRemoved, lowv3.URLLabel, l.URL.ValueNode,
+			nil, false, l, nil)
+		skipURL = true
+	}
+
+	// check if description was removed
+	if r.Description.Value == "" && l.Description.Value != "" {
+		CreateChange[*lowbase.ExternalDoc](&changes, PropertyRemoved, lowv3.DescriptionLabel, l.Description.ValueNode,
+			nil, false, l, nil)
+		skipDescription = true
+	}
+
+	// check if url was added
+	if r.URL.Value != "" && l.URL.Value == "" {
+		CreateChange[*lowbase.ExternalDoc](&changes, PropertyAdded, lowv3.URLLabel, nil,
+			r.URL.ValueNode, false, nil, r)
+		skipURL = true
+	}
+
+	// check if description was added
+	if r.Description.Value != "" && l.Description.Value == "" {
+		CreateChange[*lowbase.ExternalDoc](&changes, PropertyAdded, lowv3.DescriptionLabel, nil,
+			r.Description.ValueNode, false, nil, r)
+		skipDescription = true
+	}
+
+	// if left and right URLs are set but not equal
+	if !skipURL && l != nil && r != nil && l.URL.Value != r.URL.Value {
+		var changeType int
 		changeType = Modified
 		ctx := CreateContext(l.URL.ValueNode, r.URL.ValueNode)
 		if ctx.HasChanged() {
@@ -34,7 +67,10 @@ func CompareExternalDocs(l, r *lowbase.ExternalDoc) *ExternalDocChanges {
 		CreateChange[*lowbase.ExternalDoc](&changes, changeType, lowv3.URLLabel, l.URL.ValueNode,
 			r.URL.ValueNode, false, l, r)
 	}
-	if l != nil && r != nil && l.Description.Value != r.Description.Value {
+
+	// if left and right descriptions are set, but not equal
+	if !skipDescription && l != nil && r != nil && l.Description.Value != r.Description.Value {
+		var changeType int
 		changeType = Modified
 		ctx := CreateContext(l.Description.ValueNode, r.Description.ValueNode)
 		if ctx.HasChanged() {
@@ -43,10 +79,6 @@ func CompareExternalDocs(l, r *lowbase.ExternalDoc) *ExternalDocChanges {
 		CreateChange[*lowbase.ExternalDoc](&changes, changeType, lowv3.DescriptionLabel, l.Description.ValueNode,
 			r.Description.ValueNode, false, l, r)
 	}
-	if changeType == 0 {
-		// no change, return nothing.
-		return nil
-	}
 	dc := new(ExternalDocChanges)
 	dc.Changes = changes
 	var lExt, rExt map[low.KeyReference[string]]low.ValueReference[any]
@@ -57,5 +89,8 @@ func CompareExternalDocs(l, r *lowbase.ExternalDoc) *ExternalDocChanges {
 		rExt = r.Extensions
 	}
 	dc.ExtensionChanges = CompareExtensions(lExt, rExt)
+	if len(dc.Changes) <= 0 && dc.ExtensionChanges == nil {
+		return nil
+	}
 	return dc
 }

what-changed/external_docs_test.go

@@ -153,3 +153,109 @@ x-testing: hello`
 	extChanges := CompareExternalDocs(&lDoc, &rDoc)
 	assert.Nil(t, extChanges)
 }
+
+func TestCompareExternalDocs_DescriptionAdded(t *testing.T) {
+
+	left := `url: https://pb33f.io
+x-testing: hello`
+
+	right := `url: https://pb33f.io
+description: this is a test
+x-testing: hello`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc lowbase.ExternalDoc
+	var rDoc lowbase.ExternalDoc
+	_ = low.BuildModel(&lNode, &lDoc)
+	_ = low.BuildModel(&rNode, &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	// compare.
+	extChanges := CompareExternalDocs(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, PropertyAdded, extChanges.Changes[0].ChangeType)
+}
+
+func TestCompareExternalDocs_URLAdded(t *testing.T) {
+
+	left := `description: hi!`
+
+	right := `description: hi!
+url: https://pb33f.io`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc lowbase.ExternalDoc
+	var rDoc lowbase.ExternalDoc
+	_ = low.BuildModel(&lNode, &lDoc)
+	_ = low.BuildModel(&rNode, &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	// compare.
+	extChanges := CompareExternalDocs(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, PropertyAdded, extChanges.Changes[0].ChangeType)
+}
+
+func TestCompareExternalDocs_DescriptionRemoved(t *testing.T) {
+
+	left := `url: https://pb33f.io
+description: something`
+
+	right := `url: https://pb33f.io`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc lowbase.ExternalDoc
+	var rDoc lowbase.ExternalDoc
+	_ = low.BuildModel(&lNode, &lDoc)
+	_ = low.BuildModel(&rNode, &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	// compare.
+	extChanges := CompareExternalDocs(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, PropertyRemoved, extChanges.Changes[0].ChangeType)
+}
+
+func TestCompareExternalDocs_URLRemoved(t *testing.T) {
+
+	left := `url: https://pb33f.io
+description: something`
+
+	right := `description: something`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc lowbase.ExternalDoc
+	var rDoc lowbase.ExternalDoc
+	_ = low.BuildModel(&lNode, &lDoc)
+	_ = low.BuildModel(&rNode, &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	// compare.
+	extChanges := CompareExternalDocs(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, PropertyRemoved, extChanges.Changes[0].ChangeType)
+}