Components what-changed completed.

Now to move on to the document and finally some perform stress testing.

AND THEN! we're done with this MF. Jesus H Christ, what a mission.

what-changed/model/components_test.go

@@ -5,8 +5,9 @@ package model
 
 import (
 	"github.com/pb33f/libopenapi/datamodel/low"
-	v2 "github.com/pb33f/libopenapi/datamodel/low/v2"
-	v3low "github.com/pb33f/libopenapi/datamodel/low/v3"
+	"github.com/pb33f/libopenapi/datamodel/low/v2"
+	"github.com/pb33f/libopenapi/datamodel/low/v3"
+	"github.com/pb33f/libopenapi/index"
 	"github.com/stretchr/testify/assert"
 	"gopkg.in/yaml.v3"
 	"testing"
@@ -227,7 +228,7 @@ param3:
 	assert.Equal(t, Modified, extChanges.ParameterChanges["param1"].Changes[0].ChangeType)
 	assert.Equal(t, "WIDE AWAKE", extChanges.ParameterChanges["param1"].Changes[0].New)
 	assert.Equal(t, "KINDA SNOOZ", extChanges.ParameterChanges["param3"].Changes[0].New)
-	assert.Equal(t, v3low.NameLabel, extChanges.ParameterChanges["param1"].Changes[0].Property)
+	assert.Equal(t, v3.NameLabel, extChanges.ParameterChanges["param1"].Changes[0].Property)
 
 }
 
@@ -366,7 +367,7 @@ resp2:
 	assert.Equal(t, 1, extChanges.TotalChanges())
 	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
 	assert.Equal(t, 1, extChanges.ResponsesChanges["resp2"].TotalChanges())
-	assert.Equal(t, v3low.DescriptionLabel, extChanges.ResponsesChanges["resp2"].Changes[0].Property)
+	assert.Equal(t, v3.DescriptionLabel, extChanges.ResponsesChanges["resp2"].Changes[0].Property)
 }
 
 func TestCompareComponents_Swagger_Responses_Added(t *testing.T) {
@@ -499,5 +500,856 @@ scheme2:
 	assert.Equal(t, 1, extChanges.TotalChanges())
 	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
 	assert.Equal(t, 1, extChanges.SecuritySchemeChanges["scheme2"].TotalChanges())
-	assert.Equal(t, v3low.DescriptionLabel, extChanges.SecuritySchemeChanges["scheme2"].Changes[0].Property)
+	assert.Equal(t, v3.DescriptionLabel, extChanges.SecuritySchemeChanges["scheme2"].Changes[0].Property)
+}
+
+func TestCompareComponents_OpenAPI_Schemas_Equal(t *testing.T) {
+
+	left := `
+schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.`
+
+	right := `schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Schemas_Refs_FullBuild(t *testing.T) {
+
+	left := `components:
+  schemas:
+    coffee:
+      description: tasty
+    tv:
+      $ref: '#/components/schemas/coffee'`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+
+	idx := index.NewSpecIndex(&lNode)
+
+	_ = lDoc.Build(lNode.Content[0], idx)
+	_ = rDoc.Build(rNode.Content[0], idx)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Schemas_Modify(t *testing.T) {
+
+	left := `
+schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.`
+
+	right := `schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring, except when it is sci-fi`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+	assert.Equal(t, 1, extChanges.SchemaChanges["tv"].TotalChanges())
+	assert.Equal(t, v3.DescriptionLabel, extChanges.SchemaChanges["tv"].Changes[0].Property)
+}
+
+func TestCompareComponents_OpenAPI_Schemas_Add(t *testing.T) {
+
+	left := `
+schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.`
+
+	right := `schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.
+  herbs:
+    description: need a massive slowdown`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "herbs", extChanges.Changes[0].New)
+}
+
+func TestCompareComponents_OpenAPI_Schemas_Remove(t *testing.T) {
+
+	left := `
+schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.`
+
+	right := `schemas:
+  coffee:
+    description: tasty
+  tv:
+    description: mostly boring.
+  herbs:
+    description: need a massive slowdown`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&rDoc, &lDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 1, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "herbs", extChanges.Changes[0].Original)
+}
+
+func TestCompareComponents_OpenAPI_Responses_Equal(t *testing.T) {
+
+	left := `
+responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Responses_FullBuild(t *testing.T) {
+	left := `components:
+  responses:
+    coffee:
+      description: tasty
+    tv:
+      $ref: '#/components/responses/coffee'`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+
+	idx := index.NewSpecIndex(&lNode)
+
+	_ = lDoc.Build(lNode.Content[0], idx)
+	_ = rDoc.Build(rNode.Content[0], idx)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Responses_FullBuild_IdenticalRef(t *testing.T) {
+	left := `components:
+  responses:
+    coffee:
+      description: tasty
+    tv:
+      $ref: '#/components/responses/coffee'`
+
+	right := `components:
+  responses:
+    coffee:
+      $ref: '#/components/responses/tv'
+    tv:
+      description: tasty`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+
+	idx := index.NewSpecIndex(&lNode)
+	idx2 := index.NewSpecIndex(&rNode)
+
+	_ = lDoc.Build(lNode.Content[0], idx)
+	_ = rDoc.Build(rNode.Content[0], idx2)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Responses_Modify(t *testing.T) {
+
+	left := `responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please`
+
+	right := `responses:
+  niceResponse:
+    description: hello my matey
+  badResponse:
+    description: go away please, now!`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&rDoc, &lDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_Responses_Add(t *testing.T) {
+
+	left := `responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please!`
+
+	right := `responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please!
+  indifferent:
+    description: stay, or go, who cares?`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "indifferent", extChanges.Changes[0].New)
+}
+
+func TestCompareComponents_OpenAPI_Responses_Remove(t *testing.T) {
+
+	left := `responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please!`
+
+	right := `responses:
+  niceResponse:
+    description: hello
+  badResponse:
+    description: go away please!
+  indifferent:
+    description: stay, or go, who cares?`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&rDoc, &lDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 1, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "indifferent", extChanges.Changes[0].Original)
+}
+
+func TestCompareComponents_OpenAPI_Parameters_Equal(t *testing.T) {
+
+	left := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Parameters_Modified(t *testing.T) {
+
+	left := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param`
+
+	right := `parameters:
+  param1:
+    name: a parameter modified
+  param2:
+    name: another param but modified`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 2, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_Parameters_Added(t *testing.T) {
+
+	left := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param`
+
+	right := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param
+  param3:
+    name: do you like code?`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "param3", extChanges.Changes[0].New)
+}
+
+func TestCompareComponents_OpenAPI_Parameters_Removed(t *testing.T) {
+
+	left := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param`
+
+	right := `parameters:
+  param1:
+    name: a parameter
+  param2:
+    name: another param
+  param3:
+    name: do you like code?`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&rDoc, &lDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
+	assert.Equal(t, 1, extChanges.TotalBreakingChanges())
+	assert.Equal(t, "param3", extChanges.Changes[0].Original)
+}
+
+func TestCompareComponents_OpenAPI_Examples_Equal(t *testing.T) {
+
+	left := `examples:
+  example1:
+    description: an example
+  example2:
+    description: another example`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Examples_Modified(t *testing.T) {
+
+	left := `examples:
+  example1:
+    description: an example
+  example2:
+    description: another example`
+
+	right := `examples:
+  example1:
+    description: change me
+  example2:
+    description: grow me`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_RequestBodies_Equal(t *testing.T) {
+
+	left := `requestBodies:
+  body1:
+    description: a request
+  body2:
+    description: another request`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_RequestBodies_Modified(t *testing.T) {
+
+	left := `requestBodies:
+  body1:
+    description: a request
+  body2:
+    description: another request`
+
+	right := `requestBodies:
+  body1:
+    description: a request but changed
+  body2:
+    description: another request, also changed`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_Headers_Equal(t *testing.T) {
+
+	left := `headers:
+  header1:
+    description: a header
+  header2:
+    description: another header`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Headers_Modified(t *testing.T) {
+
+	left := `headers:
+  header1:
+    description: a header
+  header2:
+    description: another header`
+
+	right := `headers:
+  header1:
+    description: a header but different
+  header2:
+    description: another header, also different`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 0, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_SecuritySchemes_Equal(t *testing.T) {
+
+	left := `securitySchemes:
+  scheme1:
+    description: a scheme
+  scheme2:
+    description: another scheme`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Links_Equal(t *testing.T) {
+
+	left := `links:
+  link1:
+    operationId: link1
+  link2:
+    operationId: link2`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Links_Modified(t *testing.T) {
+
+	left := `links:
+  link1:
+    operationId: link1
+  link2:
+    operationId: link2`
+
+	right := `links:
+  link1:
+    operationId: somethingFresh
+  link2:
+    operationId: somethingNew`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 2, extChanges.TotalChanges())
+	assert.Equal(t, 2, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_Callbacks_Equal(t *testing.T) {
+
+	left := `callbacks:
+  link1:
+    url: https://pb33f.io
+  link2:
+    url: https://pb33f.io`
+
+	right := left
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Nil(t, extChanges)
+}
+
+func TestCompareComponents_OpenAPI_Callbacks_Modified(t *testing.T) {
+
+	left := `callbacks:
+  link1:
+    '{$request.query.queryUrl}':
+      post:
+        description: a nice callback
+  link2:
+    '{$pizza.cake.burgers}':
+      post:
+        description: pizza and cake, and burgers.`
+
+	right := `callbacks:
+  link1:
+    '{$request.query.queryUrl}':
+      post:
+        description: a nice callback, but changed
+  link2:
+    '{$pizza.cake.burgers}':
+      get:
+        description: pizza and cake, and burgers, and ketchup.`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 3, extChanges.TotalChanges())
+	assert.Equal(t, 1, extChanges.TotalBreakingChanges())
+}
+
+func TestCompareComponents_OpenAPI_Extensions_Modified(t *testing.T) {
+
+	left := `x-components: are done"`
+
+	right := `x-components: I hope`
+
+	var lNode, rNode yaml.Node
+	_ = yaml.Unmarshal([]byte(left), &lNode)
+	_ = yaml.Unmarshal([]byte(right), &rNode)
+
+	// create low level objects
+	var lDoc v3.Components
+	var rDoc v3.Components
+	_ = low.BuildModel(lNode.Content[0], &lDoc)
+	_ = low.BuildModel(rNode.Content[0], &rDoc)
+	_ = lDoc.Build(lNode.Content[0], nil)
+	_ = rDoc.Build(rNode.Content[0], nil)
+
+	// compare.
+	extChanges := CompareComponents(&lDoc, &rDoc)
+	assert.Equal(t, 1, extChanges.TotalChanges())
 }