MEDIUM: switch models generation to go-method-gen

Replaces the internal equal/diff code generator with the external
github.com/haproxytech/go-method-gen package. The new generator produces
separate per-type *_equal_generated.go and *_diff_generated.go files
instead of a single *_compare.go per source file.

Author: ivanmatmati

.gitignore

@@ -2,4 +2,6 @@
 .idea/
 bin/golangci-lint
 bin/swagger
+bin
 .envrc
+bin/go-method-gen

.gitlab-ci.yml

@@ -66,7 +66,7 @@ generate:
   tags:
     - go
   before_script:
-    - rm -rf models/*
+    - rm -rf models/*.go
     - make models
   script:
     - test -z "$(git diff 2> /dev/null)" || exit "Models are not generated, issue \`make models\` and commit the result"

Makefile

@@ -33,15 +33,25 @@ spec:
 	go run cmd/specification/*.go -file specification/haproxy-spec.yaml > specification/build/haproxy_spec.yaml
 
 .PHONY: models
-models: gentypes spec swagger-check
+models: gentypes spec swagger-check go-method-gen-check
 	./bin/swagger generate model --additional-initialism=FCGI -f ${PROJECT_PATH}/specification/build/haproxy_spec.yaml -r ${PROJECT_PATH}/specification/copyright.txt -m models -t ${PROJECT_PATH}
-	rm -rf models/server_params_prepare_for_runtime.go
-	rm -rf models/*_compare.go
-	rm -rf models/*_compare_test.go
+	./bin/go-method-gen --header-file=specification/copyright.txt --scan=models --debug --overrides=models/funcs/overrides.yaml && find ./generated -name "*.go" -exec cp {} ./models \; && rm -rf generated
 	go run cmd/struct_equal_generator/*.go -l ${PROJECT_PATH}/specification/copyright.txt ${PROJECT_PATH}/models
 	go run cmd/struct_tags_checker/*.go ${PROJECT_PATH}/models
 	go run cmd/kubebuilder_marker_generator/*.go  ${PROJECT_PATH}/models
 	go run cmd/server_params_runtime/*.go ${PROJECT_PATH}/models
+	$(MAKE) gofumpt
+
+.PHONY: go-method-gen-check
+go-method-gen-check:
+	@GO_METHOD_GEN_BIN_NAME="go-method-gen"; \
+	GO_METHOD_GEN_GITHUB="github.com/haproxytech/go-method-gen/cmd/go-method-gen@latest"; \
+	if [ -f "$$GO_METHOD_GEN_BIN_NAME" ]; then \
+		echo "✅ $$GO_METHOD_GEN_BIN_NAME already installed"; \
+	else \
+		GOBIN=$(PWD)/bin go install $$GO_METHOD_GEN_GITHUB && \
+		echo "✅ $$GO_METHOD_GEN_BIN_NAME installed"; \
+	fi
 
 .PHONY: swagger-check
 swagger-check:

cmd/struct_equal_generator/embed.go

@@ -7,8 +7,5 @@ import (
 //go:embed header.tmpl
 var tmplHeader string
 
-//go:embed generate.tmpl
-var tmplEqualAndDiff string
-
 //go:embed test.tmpl
 var tmplCompareTest string

cmd/struct_equal_generator/generate.go

@@ -6,49 +6,6 @@ import (
 )
 
 func generateEqualAndDiff(opt generateEqualAndDiffOptions) error {
-	funcMaps := template.FuncMap{
-		"HasPrefix":  strings.HasPrefix,
-		"TrimPrefix": strings.TrimPrefix,
-		"Title":      toTitle,
-		"CamelCase":  toCamelCase,
-		"LowerCase":  toLowerCase,
-		"JSON":       toJSON,
-	}
-	tmpl, err := template.New("generate.tmpl").Funcs(funcMaps).Parse(tmplEqualAndDiff)
-	if err != nil {
-		return err
-	}
-
-	data := map[string]any{
-		"Mode":              opt.Mode,
-		"Name":              opt.Name,
-		"Type":              opt.Type,
-		"Fields":            opt.Fields,
-		"NeedsOptions":      opt.NeedsOptions,
-		"NeedsOptionsIndex": opt.NeedsOptionsIndex,
-		"IsBasicType":       opt.IsBasicType,
-		"IsComplex":         opt.IsComplex,
-		"IsComparable":      opt.IsComparable,
-		"IsPointer":         opt.IsPointer,
-	}
-
-	functions := map[string]any{
-		"Functions": []any{
-			map[string]any{
-				"Name": "Equal",
-				"Data": data,
-			},
-			map[string]any{
-				"Name": "Diff",
-				"Data": data,
-			},
-		},
-	}
-
-	err = tmpl.Execute(opt.File, functions)
-	if err != nil {
-		return err
-	}
 	return generateCompareTests(opt)
 }
 

cmd/struct_equal_generator/main.go

@@ -71,7 +71,7 @@ func scanAllTypes(fileName string) []string {
 	return typesInFile
 }
 
-func generate(fileName string, args Args) (string, error) { //nolint:gocognit,maintidx
+func generate(fileName string, args Args) (string, error) { //nolint:gocognit
 	fset := token.NewFileSet()
 	var packageName string
 
@@ -81,43 +81,19 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 	}
 	sourceOfFile = string(src)
 
-	// node, err := parser.ParseFile(fset, fileName, nil, parser.ParseComments)
 	node, err := parser.ParseFile(fset, "", src, 0)
 	if err != nil {
 		return packageName, err
 	}
-	generatedFileName := strings.TrimSuffix(fileName, ".go") + "_compare.go"
 	generatedFileNameTest := strings.TrimSuffix(fileName, ".go") + "_compare_test.go"
 
-	_ = os.Truncate(generatedFileName, 0)
-	file, err := os.OpenFile(generatedFileName, os.O_CREATE|os.O_WRONLY, 0o600)
-	if err != nil {
-		return packageName, err
-	}
-	defer file.Close()
-
 	_ = os.Truncate(generatedFileNameTest, 0)
 	fileTest, err := os.OpenFile(generatedFileNameTest, os.O_CREATE|os.O_WRONLY, 0o600)
 	if err != nil {
 		return packageName, err
 	}
 	defer fileTest.Close()
 
-	// Adding the header to the generated file
-	tmpl, err := template.New("generate.tmpl").Parse(tmplHeader)
-	// ParseFiles(path.Join(templatePath))
-	if err != nil {
-		return packageName, err
-	}
-
-	err = tmpl.Execute(file, map[string]any{
-		"Package": node.Name.String(),
-		"License": args.License,
-	})
-	if err != nil {
-		return packageName, err
-	}
-
 	// Adding the header to the generated file
 	tmpl2, err := template.New("generate.tmpl").Parse(tmplHeader)
 	// ParseFiles(path.Join(templatePath))
@@ -176,7 +152,6 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 				hasTests = true
 				err = generateEqualAndDiff(generateEqualAndDiffOptions{
 					PackageName:       packageName,
-					File:              file,
 					FileTest:          fileTest,
 					Name:              currSpecType.Name.Name,
 					CurrType:          currSpecType,
@@ -192,7 +167,6 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 				hasTests = true
 				err = generateEqualAndDiff(generateEqualAndDiffOptions{
 					PackageName:  packageName,
-					File:         file,
 					FileTest:     fileTest,
 					Name:         currSpecType.Name.Name,
 					NeedsOptions: false,
@@ -211,7 +185,6 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 				}
 				err = generateEqualAndDiff(generateEqualAndDiffOptions{
 					PackageName:       packageName,
-					File:              file,
 					FileTest:          fileTest,
 					Name:              currSpecType.Name.Name,
 					Type:              res.Name,
@@ -237,7 +210,6 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 				}
 				err = generateEqualAndDiff(generateEqualAndDiffOptions{
 					PackageName:       packageName,
-					File:              file,
 					FileTest:          fileTest,
 					Name:              currSpecType.Name.Name,
 					Type:              res.Name,
@@ -265,11 +237,6 @@ func generate(fileName string, args Args) (string, error) { //nolint:gocognit,ma
 	} else {
 		os.Remove(generatedFileNameTest)
 	}
-	// Format the file
-	err = fmtFile(generatedFileName)
-	if err != nil {
-		return packageName, err
-	}
 	return packageName, nil
 }
 

cmd/struct_equal_generator/misc.go

@@ -5,7 +5,6 @@ import (
 	"os"
 	"strings"
 
-	jsoniter "github.com/json-iterator/go"
 	"golang.org/x/text/cases"
 	"golang.org/x/text/language"
 )
@@ -49,15 +48,6 @@ func toTitle(s string) string {
 	return caser.String(strings.TrimPrefix(s, "*"))
 }
 
-func toJSON(x any) string {
-	json := jsoniter.ConfigCompatibleWithStandardLibrary
-	b, err := json.Marshal(x)
-	if err != nil {
-		panic(err)
-	}
-	return string(b)
-}
-
 func toCamelCase(s string) string {
 	caser := cases.Title(language.Und)
 	words := strings.SplitSeq(s, "_")
@@ -71,19 +61,6 @@ func toCamelCase(s string) string {
 	return result
 }
 
-func toLowerCase(s string) string {
-	caser := cases.Lower(language.Und)
-	words := strings.SplitSeq(s, "_")
-	sb := strings.Builder{}
-	for word := range words {
-		sb.WriteString(caser.String(word))
-	}
-	result := sb.String()
-	result = strings.ToLower(result[:1]) + result[1:]
-
-	return result
-}
-
 // isComparable checks if a given type is comparable.
 // It takes in the name of the type as a string and returns a boolean value.
 func isComparable(typeName string) bool {

cmd/struct_equal_generator/test.tmpl

@@ -112,10 +112,11 @@ func Test{{$.Name}}{{.}}False(t *testing.T) {
 		{{- if eq $.FieldCount 0 }}
 		if len(result) == 0 {
 		{{- else  }}
+		listDiffFields := GetListOfDiffFields(result)
 			{{- if $.HasIndex }}
-				if len(result) != {{$.FieldCount}} -1 {
+		if len(result) != {{$.FieldCount}} -1 {
 			{{- else }}
-				if len(result) != {{$.FieldCount}} {
+		if len(listDiffFields) != {{$.FieldCount}} {
 			{{end -}}
 		{{end -}}
 		{{end -}}

cmd/struct_equal_generator/utils.tmpl

@@ -27,7 +27,7 @@ func equalPointers[T comparable](a, b *T) bool {
 	return *a == *b
 }
 
-func CheckSameNilAndLen[T any](s,t []T, opts ...Options) bool {
+func CheckSameNilAndLen[T any](s, t []T, opts ...Options) bool {
 	opt := getOptions(opts...)
 
 	if !opt.NilSameAsEmpty {
@@ -62,7 +62,7 @@ func CheckSameNilAndLenMap[S comparable, T any](s, t map[S]T, opts ...Options) b
 }
 
 func equalComparableSlice[T comparable](s1, s2 []T, opt Options) bool {
-    if !opt.NilSameAsEmpty {
+	if !opt.NilSameAsEmpty {
 		if s1 == nil && s2 != nil {
 			return true
 		}
@@ -82,7 +82,7 @@ func equalComparableSlice[T comparable](s1, s2 []T, opt Options) bool {
 }
 
 func equalComparableMap[T comparable](m1, m2 map[string]T, opt Options) bool {
-    if !opt.NilSameAsEmpty {
+	if !opt.NilSameAsEmpty {
 		if m1 == nil && m2 != nil {
 			return false
 		}
@@ -129,10 +129,34 @@ func equalMapStringMapSting(m1, m2 map[string]map[string]string, opt Options) bo
 		if v2, ok := m2[k1]; !ok {
 			return false
 		} else {
-			if !equalComparableMap(v1, v2, opt){
+			if !equalComparableMap(v1, v2, opt) {
 				return false
 			}
 		}
 	}
 	return true
 }
+
+func GetListOfDiffFields(diffs map[string][]interface{}) []string {
+	fields := make(map[string]struct{}, len(diffs))
+	for diff := range diffs {
+		var sb strings.Builder
+		for _, r := range diff {
+			if !(unicode.IsLetter(r) || unicode.IsNumber(r)) {
+				break
+			}
+			sb.WriteRune(r)
+		}
+		key := sb.String()
+		if key == "Metadata" {
+			continue
+		}
+		fields[key] = struct{}{}
+	}
+	result := make([]string, 0, len(fields))
+	for k := range fields {
+		result = append(result, k)
+	}
+	return result
+}
+

go.mod

@@ -16,6 +16,7 @@ require (
 	github.com/google/uuid v1.6.0
 	github.com/haproxytech/client-native/v5 v5.1.9
 	github.com/haproxytech/go-logger v1.1.0
+	github.com/haproxytech/go-method-gen v0.1.2
 	github.com/json-iterator/go v1.1.12
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51
 	github.com/mitchellh/mapstructure v1.5.0
@@ -45,14 +46,13 @@ require (
 	github.com/go-openapi/swag/typeutils v0.26.0 // indirect
 	github.com/go-openapi/swag/yamlutils v0.26.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
-	github.com/kr/text v0.2.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/oklog/ulid/v2 v2.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/rogpeppe/go-internal v1.14.1 // indirect
 	go.yaml.in/yaml/v3 v3.0.4 // indirect
 	golang.org/x/mod v0.36.0 // indirect
 	golang.org/x/net v0.54.0 // indirect
 	golang.org/x/sys v0.44.0 // indirect
+	mvdan.cc/gofumpt v0.9.1 // indirect
 )