Refactored what-changed core code to be ready for buildout.

The designs and patterns are set, the way forward for low-level models is clear. Documentation and cleanliness will now be a side by side process as the rest is built out.

Signed-off-by: Dave Shanley <dave@quobix.com>

what-changed/comparison_functions.go

@@ -0,0 +1,189 @@
+// Copyright 2022 Princess B33f Heavy Industries / Dave Shanley
+// SPDX-License-Identifier: MIT
+
+package what_changed
+
+import (
+	"github.com/pb33f/libopenapi/datamodel/low"
+	"gopkg.in/yaml.v3"
+)
+
+// CreateChange is a generic function that will create a Change of type T, populate all properties if set, and then
+// add a pointer to Change[T] in the slice of Change pointers provided
+func CreateChange[T any](changes *[]*Change[T], changeType int, property string, leftValueNode, rightValueNode *yaml.Node,
+	breaking bool, originalObject, newObject T) *[]*Change[T] {
+
+	// create a new context for the left and right nodes.
+	ctx := CreateContext(leftValueNode, rightValueNode)
+	c := &Change[T]{
+		Context:    ctx,
+		ChangeType: changeType,
+		Property:   property,
+		Breaking:   breaking,
+	}
+	// if the left is not nil, we have an original value
+	if leftValueNode != nil && leftValueNode.Value != "" {
+		c.Original = leftValueNode.Value
+	}
+	// if the right is not nil, then we have a new value
+	if rightValueNode != nil && rightValueNode.Value != "" {
+		c.New = rightValueNode.Value
+	}
+	// original and new objects
+	c.OriginalObject = originalObject
+	c.NewObject = newObject
+
+	// add the change to supplied changes slice
+	*changes = append(*changes, c)
+	return changes
+}
+
+// CreateContext will return a pointer to a ChangeContext containing the original and new line and column numbers
+// of the left and right value nodes.
+func CreateContext(l, r *yaml.Node) *ChangeContext {
+	ctx := new(ChangeContext)
+	if l != nil {
+		ctx.OriginalLine = l.Line
+		ctx.OriginalColumn = l.Column
+	} else {
+		ctx.OriginalLine = -1
+		ctx.OriginalColumn = -1
+	}
+	if r != nil {
+		ctx.NewLine = r.Line
+		ctx.NewColumn = r.Column
+	} else {
+		ctx.NewLine = -1
+		ctx.NewColumn = -1
+	}
+	return ctx
+}
+
+// CheckForObjectAdditionOrRemoval will check for the addition or removal of an object from left and right maps.
+// The label is the key to look for in the left and right maps.
+//
+// To determine this a breaking change for an addition then set breakingAdd to true (however I can't think of many
+// scenarios that adding things should break anything). Removals are generally breaking, except for non contract
+// properties like descriptions, summaries and other non-binding values, so a breakingRemove value can be tuned for
+// these circumstances.
+func CheckForObjectAdditionOrRemoval[T any](l, r map[string]*low.ValueReference[T], label string, changes *[]*Change[T],
+	breakingAdd, breakingRemove bool) {
+	var left, right T
+	if CheckObjectRemoved(l, r) {
+		left = l[label].GetValue()
+		CreateChange[T](changes, ObjectRemoved, label, l[label].GetValueNode(), nil,
+			breakingRemove, left, right)
+	}
+	if added, key := CheckObjectAdded(l, r); added {
+		right = r[key].GetValue()
+		CreateChange[T](changes, ObjectAdded, label, nil, r[key].GetValueNode(),
+			breakingAdd, left, right)
+	}
+}
+
+// CheckObjectRemoved returns true if a key/value in the left map is not present in the right.
+func CheckObjectRemoved[T any](l, r map[string]*T) bool {
+	for i := range l {
+		if r[i] == nil {
+			return true
+		}
+	}
+	return false
+}
+
+// CheckObjectAdded returns true if a key/value in the right map is not present in the left.
+func CheckObjectAdded[T any](l, r map[string]*T) (bool, string) {
+	for i := range r {
+		if l[i] == nil {
+			return true, i
+		}
+	}
+	return false, ""
+}
+
+// CheckProperties will iterate through a slice of PropertyCheck pointers of type T. The method is a convenience method
+// for running checks on the following methods in order:
+//   CheckPropertyAdditionOrRemoval
+//   CheckForModification
+//   CheckForMove
+func CheckProperties[T any](properties []*PropertyCheck[T]) {
+	for _, n := range properties {
+		CheckPropertyAdditionOrRemoval(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
+		CheckForModification(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
+		CheckForMove(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
+	}
+}
+
+// CheckPropertyAdditionOrRemoval will run both CheckForRemoval (first) and CheckForAddition (second)
+func CheckPropertyAdditionOrRemoval[T any](l, r *yaml.Node,
+	label string, changes *[]*Change[T], breaking bool, orig, new T) {
+	CheckForRemoval[T](l, r, label, changes, breaking, orig, new)
+	CheckForAddition[T](l, r, label, changes, breaking, orig, new)
+}
+
+// CheckForRemoval will check left and right yaml.Node instances for changes. Anything that is found missing on the
+// right, but present on the left, is considered a removal. A new Change[T] will be created with the type
+//
+//  PropertyRemoved
+//
+// The Change is then added to the slice of []Change[T] instances provided as a pointer.
+func CheckForRemoval[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
+	if l != nil && l.Value != "" && (r == nil || r.Value == "") {
+		CreateChange[T](changes, PropertyRemoved, label, l, r, breaking, orig, new)
+	}
+}
+
+// CheckForAddition will check left and right yaml.Node instances for changes. Anything that is found missing on the
+// left, but present on the left, is considered an addition. A new Change[T] will be created with the type
+//
+//  PropertyAdded
+//
+// The Change is then added to the slice of []Change[T] instances provided as a pointer.
+func CheckForAddition[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
+	if (l == nil || l.Value == "") && r != nil && r.Value != "" {
+		CreateChange[T](changes, PropertyAdded, label, l, r, breaking, orig, new)
+	}
+}
+
+// CheckForModification will check left and right yaml.Node instances for changes. Anything that is found in both
+// sides, but vary in value is considered a modification. CheckForModification will also check if the position of the
+// value has changed in the source documents.
+//
+// If there is no change to position, but in value the function adds a change type of Modified, if there is both a change
+// in value and a change in position, then it will be set to ModifiedAndMoved
+//
+// The Change is then added to the slice of []Change[T] instances provided as a pointer.
+func CheckForModification[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
+	if l != nil && l.Value != "" && r != nil && r.Value != "" && r.Value != l.Value {
+		changeType := Modified
+		ctx := CreateContext(l, r)
+		if ctx.HasChanged() {
+			changeType = ModifiedAndMoved
+		}
+		CreateChange[T](changes, changeType, label, l, r, breaking, orig, new)
+	}
+}
+
+// CheckForMove will check if left and right yaml.Node instances have moved position, but not changed in value. A change
+// of type Moved is created and added to changes.
+func CheckForMove[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
+	if l != nil && l.Value != "" && r != nil && r.Value != "" && r.Value == l.Value { // everything is equal
+		ctx := CreateContext(l, r)
+		if ctx.HasChanged() {
+			CreateChange[T](changes, Moved, label, l, r, breaking, orig, new)
+		}
+	}
+}
+
+// CheckExtensions is a helper method to un-pack a left and right model that contains extensions. Once unpacked
+// the extensions are compared and returns a pointer to ExtensionChanges. If nothing changed, nil is returned.
+func CheckExtensions[T low.HasExtensions[T]](l, r T) *ExtensionChanges {
+	var lExt, rExt map[low.KeyReference[string]]low.ValueReference[any]
+	if len(l.GetExtensions()) > 0 {
+		lExt = l.GetExtensions()
+	}
+	if len(r.GetExtensions()) > 0 {
+		rExt = r.GetExtensions()
+	}
+	return CompareExtensions(lExt, rExt)
+}

what-changed/contact.go

@@ -8,14 +8,19 @@ import (
 	lowv3 "github.com/pb33f/libopenapi/datamodel/low/v3"
 )
 
+// ContactChanges Represent changes to a Contact object that is a child of Info, part of an OpenAPI document.
 type ContactChanges struct {
 	PropertyChanges[*lowbase.Contact]
 }
 
+// TotalChanges represents the total number of changes that have occurred to a Contact object
 func (c *ContactChanges) TotalChanges() int {
 	return len(c.Changes)
 }
 
+// CompareContact will check a left (original) and right (new) Contact object for any changes. If there
+// were any, a pointer to a ContactChanges object is returned, otherwise if nothing changed - the function
+// returns nil.
 func CompareContact(l, r *lowbase.Contact) *ContactChanges {
 
 	var changes []*Change[*lowbase.Contact]
@@ -64,4 +69,3 @@ func CompareContact(l, r *lowbase.Contact) *ContactChanges {
 	}
 	return dc
 }
-

what-changed/extensions.go

@@ -8,10 +8,17 @@ import (
 	"strings"
 )
 
+// ExtensionChanges represents any changes to custom extensions defined for an OpenAPI object.
 type ExtensionChanges struct {
 	PropertyChanges[any]
 }
 
+// CompareExtensions will compare a left and right map of Key/ValueReference models for any changes to
+// anything. This function does not try and cast the value of an extension to perform checks, it
+// will perform a basic value check.
+//
+// A current limitation relates to extensions being objects and a property of the object changes,
+// there is currently no support for knowing anything changed - so it is ignored.
 func CompareExtensions(l, r map[low.KeyReference[string]]low.ValueReference[any]) *ExtensionChanges {
 
 	// look at the original and then look through the new.

what-changed/extensions_test.go

@@ -49,7 +49,7 @@ x-test: 1`
 
 	assert.Len(t, extChanges.Changes, 1)
 	assert.Equal(t, Moved, extChanges.Changes[0].ChangeType)
-	assert.Equal(t, 2, extChanges.Changes[0].Context.OrigLine)
+	assert.Equal(t, 2, extChanges.Changes[0].Context.OriginalLine)
 	assert.Equal(t, 1, extChanges.Changes[0].Context.NewLine)
 	assert.True(t, extChanges.Changes[0].Context.HasChanged())
 }
@@ -72,7 +72,7 @@ x-test: 1`
 
 	assert.Len(t, extChanges.Changes, 1)
 	assert.Equal(t, ModifiedAndMoved, extChanges.Changes[0].ChangeType)
-	assert.Equal(t, 2, extChanges.Changes[0].Context.OrigLine)
+	assert.Equal(t, 2, extChanges.Changes[0].Context.OriginalLine)
 	assert.Equal(t, 1, extChanges.Changes[0].Context.NewLine)
 	assert.Equal(t, "1", extChanges.Changes[0].Original)
 	assert.Equal(t, "2", extChanges.Changes[0].New)
@@ -97,7 +97,7 @@ x-test: 1`
 
 	assert.Len(t, extChanges.Changes, 1)
 	assert.Equal(t, ObjectRemoved, extChanges.Changes[0].ChangeType)
-	assert.Equal(t, 2, extChanges.Changes[0].Context.OrigLine)
+	assert.Equal(t, 2, extChanges.Changes[0].Context.OriginalLine)
 	assert.Equal(t, -1, extChanges.Changes[0].Context.NewLine)
 	assert.Equal(t, "1", extChanges.Changes[0].Original)
 	assert.True(t, extChanges.Changes[0].Context.HasChanged())
@@ -121,7 +121,7 @@ x-test: 1`
 
 	assert.Len(t, extChanges.Changes, 1)
 	assert.Equal(t, ObjectAdded, extChanges.Changes[0].ChangeType)
-	assert.Equal(t, -1, extChanges.Changes[0].Context.OrigLine)
+	assert.Equal(t, -1, extChanges.Changes[0].Context.OriginalLine)
 	assert.Equal(t, 2, extChanges.Changes[0].Context.NewLine)
 	assert.Equal(t, "1", extChanges.Changes[0].New)
 	assert.True(t, extChanges.Changes[0].Context.HasChanged())

what-changed/external_docs.go

@@ -8,11 +8,13 @@ import (
 	lowv3 "github.com/pb33f/libopenapi/datamodel/low/v3"
 )
 
+// ExternalDocChanges represents changes made to any ExternalDoc object from an OpenAPI document.
 type ExternalDocChanges struct {
 	PropertyChanges[*lowbase.ExternalDoc]
 	ExtensionChanges *ExtensionChanges
 }
 
+// TotalChanges returns a count of everything that changed
 func (e *ExternalDocChanges) TotalChanges() int {
 	c := len(e.Changes)
 	if e.ExtensionChanges != nil {
@@ -21,6 +23,9 @@ func (e *ExternalDocChanges) TotalChanges() int {
 	return c
 }
 
+// CompareExternalDocs will compare a left (original) and a right (new) slice of ValueReference
+// nodes for any changes between them. If there are changes, then a pointer to ExternalDocChanges
+// is returned, otherwise if nothing changed - then nil is returned.
 func CompareExternalDocs(l, r *lowbase.ExternalDoc) *ExternalDocChanges {
 	var changes []*Change[*lowbase.ExternalDoc]
 	var props []*PropertyCheck[*lowbase.ExternalDoc]

what-changed/external_docs_test.go

@@ -46,7 +46,7 @@ x-testing: hiya!`
 	assert.False(t, urlChange.Context.HasChanged())
 	assert.Equal(t, "https://pb33f.io", urlChange.Original)
 	assert.Equal(t, "https://quobix.com", urlChange.New)
-	assert.Equal(t, 1, urlChange.Context.OrigLine)
+	assert.Equal(t, 1, urlChange.Context.OriginalLine)
 	assert.Equal(t, lowv3.URLLabel, urlChange.Property)
 
 	descChange := extChanges.Changes[1]
@@ -54,8 +54,8 @@ x-testing: hiya!`
 	assert.False(t, descChange.Context.HasChanged())
 	assert.Equal(t, "this is another test", descChange.New)
 	assert.Equal(t, "this is a test", descChange.Original)
-	assert.Equal(t, 2, descChange.Context.OrigLine)
-	assert.Equal(t, 14, descChange.Context.OrigCol)
+	assert.Equal(t, 2, descChange.Context.OriginalLine)
+	assert.Equal(t, 14, descChange.Context.OriginalColumn)
 
 	// validate extensions
 	extChange := extChanges.ExtensionChanges.Changes[0]
@@ -63,8 +63,8 @@ x-testing: hiya!`
 	assert.False(t, extChange.Context.HasChanged())
 	assert.Equal(t, "hiya!", extChange.New)
 	assert.Equal(t, "hello", extChange.Original)
-	assert.Equal(t, 3, extChange.Context.OrigLine)
-	assert.Equal(t, 12, extChange.Context.OrigCol)
+	assert.Equal(t, 3, extChange.Context.OriginalLine)
+	assert.Equal(t, 12, extChange.Context.OriginalColumn)
 
 }
 
@@ -101,7 +101,7 @@ url: https://quobix.com`
 	assert.True(t, urlChange.Context.HasChanged())
 	assert.Equal(t, "https://pb33f.io", urlChange.Original)
 	assert.Equal(t, "https://quobix.com", urlChange.New)
-	assert.Equal(t, 1, urlChange.Context.OrigLine)
+	assert.Equal(t, 1, urlChange.Context.OriginalLine)
 	assert.Equal(t, 3, urlChange.Context.NewLine)
 	assert.Equal(t, lowv3.URLLabel, urlChange.Property)
 
@@ -110,10 +110,10 @@ url: https://quobix.com`
 	assert.True(t, descChange.Context.HasChanged())
 	assert.Equal(t, "this is another test", descChange.New)
 	assert.Equal(t, "this is a test", descChange.Original)
-	assert.Equal(t, 2, descChange.Context.OrigLine)
-	assert.Equal(t, 14, descChange.Context.OrigCol)
+	assert.Equal(t, 2, descChange.Context.OriginalLine)
+	assert.Equal(t, 14, descChange.Context.OriginalColumn)
 	assert.Equal(t, 1, descChange.Context.NewLine)
-	assert.Equal(t, 14, descChange.Context.NewCol)
+	assert.Equal(t, 14, descChange.Context.NewColumn)
 
 	// validate extensions
 	extChange := extChanges.ExtensionChanges.Changes[0]
@@ -121,10 +121,10 @@ url: https://quobix.com`
 	assert.True(t, extChange.Context.HasChanged())
 	assert.Equal(t, "hiya!", extChange.New)
 	assert.Equal(t, "hello", extChange.Original)
-	assert.Equal(t, 3, extChange.Context.OrigLine)
-	assert.Equal(t, 12, extChange.Context.OrigCol)
+	assert.Equal(t, 3, extChange.Context.OriginalLine)
+	assert.Equal(t, 12, extChange.Context.OriginalColumn)
 	assert.Equal(t, 2, extChange.Context.NewLine)
-	assert.Equal(t, 12, extChange.Context.NewCol)
+	assert.Equal(t, 12, extChange.Context.NewColumn)
 }
 
 func TestCompareExternalDocs_Identical(t *testing.T) {

what-changed/models.go

@@ -0,0 +1,117 @@
+// Copyright 2022 Princess B33f Heavy Industries / Dave Shanley
+// SPDX-License-Identifier: MIT
+
+package what_changed
+
+import "gopkg.in/yaml.v3"
+
+// Definitions of the possible changes between two items
+const (
+
+	// Modified means that was a modification of a value was made
+	Modified = iota + 1
+
+	// PropertyAdded means that a new property to an object was added
+	PropertyAdded
+
+	// ObjectAdded means that a new object was added
+	ObjectAdded
+
+	// ObjectRemoved means that an object was removed
+	ObjectRemoved
+
+	// PropertyRemoved means that a property of an object was removed
+	PropertyRemoved
+
+	// Moved means that a property or an object was moved, but unchanged (line/columns changed)
+	Moved
+
+	// ModifiedAndMoved means that a property was modified, and it was also moved.
+	ModifiedAndMoved
+)
+
+// WhatChanged is a summary object that contains a high level summary of everything changed.
+type WhatChanged struct {
+	Added            int
+	Removed          int
+	ModifiedAndMoved int
+	Modified         int
+	Moved            int
+	TotalChanges     int
+	Changes          *Changes
+}
+
+// ChangeContext holds a reference to the line and column positions of original and new change.
+type ChangeContext struct {
+	OriginalLine   int
+	OriginalColumn int
+	NewLine        int
+	NewColumn      int
+}
+
+// HasChanged determines if the line and column numbers of the original and new values have changed.
+func (c *ChangeContext) HasChanged() bool {
+	return c.NewLine != c.OriginalLine || c.NewColumn != c.OriginalColumn
+}
+
+// Change represents a change between two different elements inside an OpenAPI specification.
+type Change[T any] struct {
+
+	// Context represents the lines and column numbers of the original and new changes.
+	Context *ChangeContext
+
+	// ChangeType represents the type of change that occurred. stored as an integer, defined by constants above.
+	ChangeType int
+
+	// Property is the property name key being changed.
+	Property string
+
+	// Original is the original value represented as a string.
+	Original string
+
+	// New is the new value represented as a string.
+	New string
+
+	// Breaking determines if the change is a breaking one or not.
+	Breaking bool
+
+	// OriginalObject represents the original object that was changed.
+	OriginalObject T
+
+	// NewObject represents the new object that has been modified.
+	NewObject T
+}
+
+// PropertyChanges holds a slice of Change[T] change pointers
+type PropertyChanges[T any] struct {
+	Changes []*Change[T]
+}
+
+// PropertyCheck is used by functions to check the state of left and right values.
+type PropertyCheck[T any] struct {
+
+	// Original is the property we're checking on the left
+	Original T
+
+	// New is s the property we're checking on the right
+	New T
+
+	// Label is the identifier we're looking for on the left and right hand sides
+	Label string
+
+	// LeftNode is the yaml.Node pointer that holds the original node structure of the value
+	LeftNode *yaml.Node
+
+	// RightNode is the yaml.Node pointer that holds the new node structure of the value
+	RightNode *yaml.Node
+
+	// Breaking determines if the check is a breaking change (modifications or removals etc.)
+	Breaking bool
+
+	// Changes represents a pointer to the slice to contain all changes found.
+	Changes *[]*Change[T]
+}
+
+type Changes struct {
+	TagChanges *TagChanges
+}

what-changed/tags.go

@@ -10,12 +10,14 @@ import (
 	"strings"
 )
 
+// TagChanges represents changes made to the Tags object of an OpenAPI document.
 type TagChanges struct {
 	PropertyChanges[*lowbase.Tag]
 	ExternalDocs     *ExternalDocChanges
 	ExtensionChanges *ExtensionChanges
 }
 
+// TotalChanges returns a count of everything that changed within tags.
 func (t *TagChanges) TotalChanges() int {
 	c := len(t.Changes)
 	if t.ExternalDocs != nil {
@@ -27,6 +29,9 @@ func (t *TagChanges) TotalChanges() int {
 	return c
 }
 
+// CompareTags will compare a left (original) and a right (new) slice of ValueReference nodes for
+// any changes between them. If there are changes, a pointer to TagChanges is returned, if not then
+// nil is returned instead.
 func CompareTags(l, r []low.ValueReference[*lowbase.Tag]) *TagChanges {
 	tc := new(TagChanges)
 

what-changed/tags_test.go

@@ -159,13 +159,13 @@ tags:
 
 	nameChange := changes.Changes[0]
 	assert.Equal(t, Moved, nameChange.ChangeType)
-	assert.Equal(t, 4, nameChange.Context.OrigLine)
+	assert.Equal(t, 4, nameChange.Context.OriginalLine)
 	assert.Equal(t, 3, nameChange.Context.NewLine)
 	assert.True(t, nameChange.Context.HasChanged())
 
 	descChange := changes.Changes[1]
 	assert.Equal(t, Moved, descChange.ChangeType)
-	assert.Equal(t, 3, descChange.Context.OrigLine)
+	assert.Equal(t, 3, descChange.Context.OriginalLine)
 	assert.Equal(t, 5, descChange.Context.NewLine)
 	assert.True(t, descChange.Context.HasChanged())
 
@@ -206,7 +206,7 @@ tags:
 
 	nameChange := changes.Changes[0]
 	assert.Equal(t, Moved, nameChange.ChangeType)
-	assert.Equal(t, 4, nameChange.Context.OrigLine)
+	assert.Equal(t, 4, nameChange.Context.OriginalLine)
 	assert.Equal(t, 8, nameChange.Context.NewLine)
 	assert.True(t, nameChange.Context.HasChanged())
 }
@@ -246,7 +246,7 @@ tags:
 
 	descChange := changes.Changes[1]
 	assert.Equal(t, ModifiedAndMoved, descChange.ChangeType)
-	assert.Equal(t, 3, descChange.Context.OrigLine)
+	assert.Equal(t, 3, descChange.Context.OriginalLine)
 	assert.Equal(t, 5, descChange.Context.NewLine)
 	assert.Equal(t, "a lovelier tag description", descChange.Original)
 	assert.Equal(t, "a different tag description", descChange.New)

what-changed/what_changed.go

@@ -3,197 +3,3 @@
 
 package what_changed
 
-import (
-	"github.com/pb33f/libopenapi/datamodel/low"
-	"gopkg.in/yaml.v3"
-)
-
-const (
-	Modified = iota + 1
-	PropertyAdded
-	ObjectAdded
-	ObjectRemoved
-	PropertyRemoved
-	Moved
-	ModifiedAndMoved
-)
-
-type WhatChanged struct {
-	Added        int
-	Removed      int
-	Modified     int
-	Moved        int
-	TotalChanges int
-	Changes      *Changes
-}
-
-type ChangeContext struct {
-	OrigLine int
-	OrigCol  int
-	NewLine  int
-	NewCol   int
-}
-
-func (c *ChangeContext) HasChanged() bool {
-	return c.NewLine != c.OrigLine || c.NewCol != c.OrigCol
-}
-
-type Change[T any] struct {
-	Context        *ChangeContext
-	ChangeType     int
-	Property       string
-	Original       string
-	New            string
-	Breaking       bool
-	OriginalObject T
-	NewObject      T
-}
-
-type PropertyChanges[T any] struct {
-	Changes []*Change[T]
-}
-
-type Changes struct {
-	TagChanges *TagChanges
-}
-
-func CreateChange[T any](changes *[]*Change[T], changeType int, property string, leftValueNode, rightValueNode *yaml.Node,
-	breaking bool, originalObject, newObject T) *[]*Change[T] {
-
-	ctx := CreateContext(leftValueNode, rightValueNode)
-	c := &Change[T]{
-		Context:    ctx,
-		ChangeType: changeType,
-		Property:   property,
-		Breaking:   breaking,
-	}
-	if leftValueNode != nil && leftValueNode.Value != "" {
-		c.Original = leftValueNode.Value
-	}
-	if rightValueNode != nil && rightValueNode.Value != "" {
-		c.New = rightValueNode.Value
-	}
-	c.OriginalObject = originalObject
-	c.NewObject = newObject
-	*changes = append(*changes, c)
-	return changes
-}
-
-func CreateContext(l, r *yaml.Node) *ChangeContext {
-	ctx := new(ChangeContext)
-	if l != nil {
-		ctx.OrigLine = l.Line
-		ctx.OrigCol = l.Column
-	} else {
-		ctx.OrigLine = -1
-		ctx.OrigCol = -1
-	}
-	if r != nil {
-		ctx.NewLine = r.Line
-		ctx.NewCol = r.Column
-	} else {
-		ctx.NewLine = -1
-		ctx.NewCol = -1
-	}
-	return ctx
-}
-
-type PropertyCheck[T any] struct {
-	Original  T
-	New       T
-	Label     string
-	LeftNode  *yaml.Node
-	RightNode *yaml.Node
-	Breaking  bool
-	Changes   *[]*Change[T]
-}
-
-func CheckForObjectAdditionOrRemoval[T any](l, r map[string]*low.ValueReference[T], label string, changes *[]*Change[T],
-	breakingAdd, breakingRemove bool) {
-	var left, right T
-	if CheckObjectRemoved(l, r) {
-		left = l[label].GetValue()
-		CreateChange[T](changes, ObjectRemoved, label, l[label].GetValueNode(), nil,
-			breakingRemove, left, right)
-	}
-	if added, key := CheckObjectAdded(l, r); added {
-		right = r[key].GetValue()
-		CreateChange[T](changes, ObjectAdded, label, nil, r[key].GetValueNode(),
-			breakingAdd, left, right)
-	}
-}
-
-func CheckObjectRemoved[T any](l, r map[string]*T) bool {
-	for i := range l {
-		if r[i] == nil {
-			return true
-		}
-	}
-	return false
-}
-
-func CheckObjectAdded[T any](l, r map[string]*T) (bool, string) {
-	for i := range r {
-		if l[i] == nil {
-			return true, i
-		}
-	}
-	return false, ""
-}
-
-func CheckProperties[T any](properties []*PropertyCheck[T]) {
-	for _, n := range properties {
-		CheckPropertyAdditionOrRemoval(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
-		CheckForModification(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
-		CheckForMove(n.LeftNode, n.RightNode, n.Label, n.Changes, n.Breaking, n.Original, n.New)
-	}
-}
-
-func CheckPropertyAdditionOrRemoval[T any](l, r *yaml.Node,
-	label string, changes *[]*Change[T], breaking bool, orig, new T) {
-	CheckForRemoval[T](l, r, label, changes, breaking, orig, new)
-	CheckForAddition[T](l, r, label, changes, breaking, orig, new)
-}
-
-func CheckForRemoval[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
-	if l != nil && l.Value != "" && (r == nil || r.Value == "") {
-		CreateChange[T](changes, PropertyRemoved, label, l, r, breaking, orig, new)
-	}
-}
-
-func CheckForAddition[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
-	if (l == nil || l.Value == "") && r != nil && r.Value != "" {
-		CreateChange[T](changes, PropertyAdded, label, l, r, breaking, orig, new)
-	}
-}
-
-func CheckForModification[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
-	if l != nil && l.Value != "" && r != nil && r.Value != "" && r.Value != l.Value {
-		changeType := Modified
-		ctx := CreateContext(l, r)
-		if ctx.HasChanged() {
-			changeType = ModifiedAndMoved
-		}
-		CreateChange[T](changes, changeType, label, l, r, breaking, orig, new)
-	}
-}
-
-func CheckForMove[T any](l, r *yaml.Node, label string, changes *[]*Change[T], breaking bool, orig, new T) {
-	if l != nil && l.Value != "" && r != nil && r.Value != "" && r.Value == l.Value { // everything is equal
-		ctx := CreateContext(l, r)
-		if ctx.HasChanged() {
-			CreateChange[T](changes, Moved, label, l, r, breaking, orig, new)
-		}
-	}
-}
-
-func CheckExtensions[T low.HasExtensions[T]](l, r T) *ExtensionChanges {
-	var lExt, rExt map[low.KeyReference[string]]low.ValueReference[any]
-	if len(l.GetExtensions()) > 0 {
-		lExt = l.GetExtensions()
-	}
-	if len(r.GetExtensions()) > 0 {
-		rExt = r.GetExtensions()
-	}
-	return CompareExtensions(lExt, rExt)
-}