feat(tfbuilder): add more assertion functions

tfbuilder/assertions.go

@@ -0,0 +1,18 @@
+package tfbuilder
+
+import (
+	"github.com/hashicorp/terraform-plugin-testing/helper/resource"
+	"github.com/hashicorp/terraform-plugin-testing/plancheck"
+)
+
+func CheckReapplyPlanEmpty(builder *Builder) resource.TestStep {
+	return resource.TestStep{
+		// Re-apply the same config and ensure no changes occur
+		Config: builder.Build(),
+		ConfigPlanChecks: resource.ConfigPlanChecks{
+			PreApply: []plancheck.PlanCheck{
+				plancheck.ExpectEmptyPlan(),
+			},
+		},
+	}
+}

tfbuilder/builder_test.go

@@ -27,7 +27,10 @@ func TestBuilder_KongMeshWithPolicy(t *testing.T) {
 			WithLabels(map[string]string{
 				"kuma.io/mesh": "kong-mesh_mesh.default.name",
 			}).
-			WithSpecHCL(tfbuilder.AllowAllTrafficPermissionSpec),
+			WithSpec(tfbuilder.AllowAllTrafficPermissionSpec).
+			AddToSpec(`kind = "Mesh"`, `proxy_types = ["Sidecar"]`).
+			UpdateSpec(`kind = "Mesh"`, `kind = "MeshSubset"`).
+			RemoveFromSpec(`action = "Allow"`),
 	)
 
 	actual := builder.Build()

tfbuilder/go.mod

@@ -2,10 +2,64 @@ module github.com/Kong/shared-speakeasy/tfbuilder
 
 go 1.24.1
 
-require github.com/stretchr/testify v1.10.0
+require (
+	github.com/hashicorp/terraform-plugin-testing v1.12.0
+	github.com/stretchr/testify v1.10.0
+)
 
 require (
+	github.com/ProtonMail/go-crypto v1.1.3 // indirect
+	github.com/agext/levenshtein v1.2.2 // indirect
+	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
+	github.com/cloudflare/circl v1.3.7 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/fatih/color v1.16.0 // indirect
+	github.com/golang/protobuf v1.5.4 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
+	github.com/hashicorp/errwrap v1.0.0 // indirect
+	github.com/hashicorp/go-checkpoint v0.5.0 // indirect
+	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
+	github.com/hashicorp/go-cty v1.5.0 // indirect
+	github.com/hashicorp/go-hclog v1.6.3 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/go-plugin v1.6.2 // indirect
+	github.com/hashicorp/go-retryablehttp v0.7.7 // indirect
+	github.com/hashicorp/go-uuid v1.0.3 // indirect
+	github.com/hashicorp/go-version v1.7.0 // indirect
+	github.com/hashicorp/hc-install v0.9.1 // indirect
+	github.com/hashicorp/hcl/v2 v2.23.0 // indirect
+	github.com/hashicorp/logutils v1.0.0 // indirect
+	github.com/hashicorp/terraform-exec v0.22.0 // indirect
+	github.com/hashicorp/terraform-json v0.24.0 // indirect
+	github.com/hashicorp/terraform-plugin-go v0.26.0 // indirect
+	github.com/hashicorp/terraform-plugin-log v0.9.0 // indirect
+	github.com/hashicorp/terraform-plugin-sdk/v2 v2.36.1 // indirect
+	github.com/hashicorp/terraform-registry-address v0.2.4 // indirect
+	github.com/hashicorp/terraform-svchost v0.1.1 // indirect
+	github.com/hashicorp/yamux v0.1.1 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mitchellh/copystructure v1.2.0 // indirect
+	github.com/mitchellh/go-testing-interface v1.14.1 // indirect
+	github.com/mitchellh/go-wordwrap v1.0.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/oklog/run v1.0.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/vmihailenco/msgpack v4.0.4+incompatible // indirect
+	github.com/vmihailenco/msgpack/v5 v5.4.1 // indirect
+	github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
+	github.com/zclconf/go-cty v1.16.2 // indirect
+	golang.org/x/crypto v0.36.0 // indirect
+	golang.org/x/mod v0.22.0 // indirect
+	golang.org/x/net v0.37.0 // indirect
+	golang.org/x/sync v0.12.0 // indirect
+	golang.org/x/sys v0.31.0 // indirect
+	golang.org/x/text v0.23.0 // indirect
+	golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d // indirect
+	google.golang.org/appengine v1.6.8 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20241015192408-796eee8c2d53 // indirect
+	google.golang.org/grpc v1.69.4 // indirect
+	google.golang.org/protobuf v1.36.3 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

tfbuilder/mesh.go

@@ -36,6 +36,21 @@ func (m *MeshBuilder) WithDependsOn(deps ...string) *MeshBuilder {
 	return m
 }
 
+func (m *MeshBuilder) AddToSpec(after, newLine string) *MeshBuilder {
+	m.Spec = addToSpec(m.Spec, after, newLine)
+	return m
+}
+
+func (m *MeshBuilder) RemoveFromSpec(match string) *MeshBuilder {
+	m.Spec = removeFromSpec(m.Spec, match)
+	return m
+}
+
+func (m *MeshBuilder) UpdateSpec(match, newValue string) *MeshBuilder {
+	m.Spec = updateSpec(m.Spec, match, newValue)
+	return m
+}
+
 func (m *MeshBuilder) Render(provider *Builder) string {
 	data := map[string]interface{}{
 		"Provider":         provider.provider,

tfbuilder/plan.go

@@ -0,0 +1,24 @@
+package tfbuilder
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+
+	"github.com/hashicorp/terraform-plugin-testing/plancheck"
+)
+
+type debugPlan struct{}
+
+func (e debugPlan) CheckPlan(ctx context.Context, req plancheck.CheckPlanRequest, resp *plancheck.CheckPlanResponse) {
+	reqPlan, err := json.Marshal(req.Plan)
+	if err != nil {
+		log.Fatalf("error marshaling plan request: %s", err)
+	}
+	reqPlanStr := string(reqPlan)
+	log.Printf("req.Plan - %s\n", reqPlanStr)
+}
+
+func DebugPlan() plancheck.PlanCheck {
+	return debugPlan{}
+}

tfbuilder/policy.go

@@ -28,7 +28,7 @@ type PolicyBuilder struct {
 	Labels       map[string]string
 	PolicyName   string
 	Type         string
-	SpecHCL      string // literal HCL block
+	Spec         string // literal HCL block
 	CPID         string // Optional
 }
 
@@ -57,8 +57,8 @@ func (p *PolicyBuilder) WithDependsOn(deps ...string) *PolicyBuilder {
 	return p
 }
 
-func (p *PolicyBuilder) WithSpecHCL(hcl string) *PolicyBuilder {
-	p.SpecHCL = hcl
+func (p *PolicyBuilder) WithSpec(hcl string) *PolicyBuilder {
+	p.Spec = hcl
 	return p
 }
 
@@ -67,6 +67,21 @@ func (p *PolicyBuilder) WithCPID(cpID string) *PolicyBuilder {
 	return p
 }
 
+func (p *PolicyBuilder) AddToSpec(after, newLine string) *PolicyBuilder {
+	p.Spec = addToSpec(p.Spec, after, newLine)
+	return p
+}
+
+func (p *PolicyBuilder) RemoveFromSpec(match string) *PolicyBuilder {
+	p.Spec = removeFromSpec(p.Spec, match)
+	return p
+}
+
+func (p *PolicyBuilder) UpdateSpec(match, newValue string) *PolicyBuilder {
+	p.Spec = updateSpec(p.Spec, match, newValue)
+	return p
+}
+
 func (p *PolicyBuilder) Render(provider *Builder) string {
 	tmplBytes, err := templatesFS.ReadFile("templates/policy.tmpl")
 	if err != nil {
@@ -89,7 +104,7 @@ func (p *PolicyBuilder) Render(provider *Builder) string {
 		"Labels":           p.Labels,
 		"Name":             p.PolicyName,
 		"Type":             p.Type,
-		"Spec":             p.SpecHCL,
+		"Spec":             p.Spec,
 		"CPID":             p.CPID,
 	}); err != nil {
 		panic(err)

tfbuilder/spec.go

@@ -0,0 +1,56 @@
+package tfbuilder
+
+import (
+	"log"
+	"strings"
+)
+
+func addToSpec(spec string, after, newLine string) string {
+	lines := strings.Split(spec, "\n")
+	var result []string
+	inserted := false
+
+	for i := 0; i < len(lines); i++ {
+		line := lines[i]
+		result = append(result, line)
+
+		if !inserted && strings.Contains(line, after) {
+			indent := getIndentation(line)
+			result = append(result, indent+newLine)
+			inserted = true
+		}
+	}
+
+	if !inserted {
+		log.Fatalf("AddToSpec failed: could not find line containing: %q", after)
+	}
+
+	return strings.Join(result, "\n")
+}
+
+func removeFromSpec(spec string, match string) string {
+	lines := strings.Split(spec, "\n")
+	var filtered []string
+	for _, l := range lines {
+		if !strings.Contains(l, match) {
+			filtered = append(filtered, l)
+		}
+	}
+	return strings.Join(filtered, "\n")
+}
+
+func updateSpec(spec, match, newValue string) string {
+	return strings.ReplaceAll(spec, match, newValue)
+}
+
+func getIndentation(line string) string {
+	indent := ""
+	for _, r := range line {
+		if r == ' ' || r == '\t' {
+			indent += string(r)
+		} else {
+			break
+		}
+	}
+	return indent
+}

tfbuilder/testdata/expected_kong_mesh_with_policy.tf

@@ -25,10 +25,10 @@ resource "kong-mesh_mesh_traffic_permission" "allow_all" {
     from = [
       {
         target_ref = {
-          kind = "Mesh"
+          kind = "MeshSubset"
+          proxy_types = ["Sidecar"]
         }
         default = {
-          action = "Allow"
         }
       }
     ]