Merge pull request #6 from ing-bank/feature/linter

Add linter to makefile, configuration and fix few linting issues

.golangci.yaml

@@ -0,0 +1,86 @@
+linters-settings:
+  gocritic:
+    disabled-checks:
+      - "paramTypeCombine"
+    enabled-tags:
+      - "performance"
+      - "style"
+      - "diagnostic"
+linters:
+  enable:
+    - asasalint
+    - asciicheck
+    - bidichk
+    - bodyclose
+    - containedctx
+    - contextcheck
+    - cyclop
+    - decorder
+    - dogsled
+    - dupword
+    - durationcheck
+    - errcheck
+    - errname
+    - errorlint
+    - execinquery
+    - exhaustive
+    - exportloopref
+    - forbidigo
+    - ginkgolinter
+    - gocheckcompilerdirectives
+    - gochecknoinits
+    - gocognit
+    - goconst
+    - gocritic
+    - gocyclo
+    - goerr113
+    - gofmt
+    - gofumpt
+    - goheader
+    - goimports
+    - gomoddirectives
+    - gomodguard
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - gosmopolitan
+    - govet
+    - grouper
+    - ifshort
+    - importas
+    - ineffassign
+    - interfacebloat
+    - interfacer
+    - ireturn
+    - loggercheck
+    - maintidx
+    - makezero
+    - mirror
+    - misspell
+    - musttag
+    - nakedret
+    - nestif
+    - nilerr
+    - nilnil
+    - nlreturn
+    - nonamedreturns
+    - nosprintfhostport
+    - paralleltest
+    - prealloc
+    - predeclared
+    - promlinter
+    - reassign
+    - rowserrcheck
+    - sqlclosecheck
+    - staticcheck
+    - tenv
+    - thelper
+    - tparallel
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    - usestdlibvars
+    - wastedassign
+    - whitespace
+    - zerologlint

Makefile

@@ -12,4 +12,11 @@ test: fmt ## Run unit tests, alias: t
 
 fmt: ## Format go code
 	@go mod tidy
-	@go fmt ./...
+	@gofumpt -l -w .
+
+tools: ## Install extra tools for development
+	go install mvdan.cc/gofumpt@latest
+	go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+
+lint: ## Lint the code locally
+	golangci-lint run

generator.go

@@ -4,10 +4,11 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"github.com/survivorbat/go-tsyncmap"
 	"reflect"
 	"regexp"
 	"strings"
+
+	"github.com/survivorbat/go-tsyncmap"
 )
 
 // typeCacheMap is used to easily fetch json keys from a type
@@ -20,6 +21,8 @@ type iKind[T any] interface {
 }
 
 // ensureConcrete ensures that the given value is a value and not a pointer, if it is, convert it to its element type
+//
+//nolint:ireturn // Does not matter in this context
 func ensureConcrete[T iKind[T]](value T) T {
 	if value.Kind() == reflect.Ptr {
 		return ensureConcrete[T](value.Elem())
@@ -28,11 +31,14 @@ func ensureConcrete[T iKind[T]](value T) T {
 	return value
 }
 
+// errNotAStruct can be exported in the future if need be
+var errNotAStruct = errors.New("object is not a struct")
+
 // getFieldNameFromJson returns the field name from the json tag
 func getFieldNameFromJson(object any, jsonKey string) (string, error) {
 	typeInfo := ensureConcrete(reflect.TypeOf(object))
 	if typeInfo.Kind() != reflect.Struct {
-		return "", errors.New("object is not a struct")
+		return "", errNotAStruct
 	}
 
 	typeName := typeNameOf(object)
@@ -62,6 +68,7 @@ func getFieldNameFromJson(object any, jsonKey string) (string, error) {
 	}
 
 	typeCacheMap.Store(typeName, typeCache)
+
 	return typeCache[jsonKey], nil
 }
 
@@ -95,7 +102,7 @@ func injectLinks(registry LinkRegistry, object any, result map[string]any) {
 
 			// Replace the {name} with the actual value
 			matchString := fmt.Sprintf("{%s}", match[1])
-			linkInfo.Href = strings.Replace(linkInfo.Href, matchString, fmt.Sprintf("%v", urlValue), -1)
+			linkInfo.Href = strings.ReplaceAll(linkInfo.Href, matchString, fmt.Sprintf("%v", urlValue))
 		}
 
 		// Save the linkInfo in the object
@@ -159,6 +166,7 @@ func InjectLinks(registry LinkRegistry, object any) []byte {
 
 	var resultObject any
 
+	//nolint:exhaustive // Doesn't make sense to add more here
 	switch ensureConcrete(reflect.ValueOf(object)).Kind() {
 	case reflect.Slice, reflect.Struct, reflect.Array:
 		_ = json.Unmarshal(rawResponseJson, &resultObject)
@@ -170,5 +178,6 @@ func InjectLinks(registry LinkRegistry, object any) []byte {
 	}
 
 	finalResponse, _ := json.Marshal(resultObject)
+
 	return finalResponse
 }

generator_test.go

@@ -3,11 +3,12 @@ package gohateoas
 import (
 	"encoding/json"
 	"fmt"
-	"github.com/stretchr/testify/assert"
 	"net/http"
 	"reflect"
 	"testing"
 	"time"
+
+	"github.com/stretchr/testify/assert"
 )
 
 type cupcake struct {
@@ -503,8 +504,7 @@ func TestInjectLinks_CreatesExpectedJsonWithDeeperSlice(t *testing.T) {
 }
 
 // empty is used as a dummy to make sure the if-statement in InjectLinks doesn't halt execution on no registered links
-type empty struct {
-}
+type empty struct{}
 
 func TestInjectLinks_ReturnsJsonOnUnknownType(t *testing.T) {
 	t.Parallel()
@@ -595,8 +595,7 @@ func TestInjectLinks_IgnoresOnNonStructSlices(t *testing.T) {
 func TestInjectLinks_IgnoresIfRegistryIsEmpty(t *testing.T) {
 	t.Parallel()
 	// Arrange
-	type testType3 struct {
-	}
+	type testType3 struct{}
 
 	registry := NewLinkRegistry()
 
@@ -851,13 +850,12 @@ func BenchmarkInjectLinks(b *testing.B) {
 
 	registryTests := map[string]func() LinkRegistry{
 		// This test won't do much because there's an if-statement blocking execution, but it gives us a bit of insight
-		"no links": func() LinkRegistry {
-			return NewLinkRegistry()
-		},
+		"no links": NewLinkRegistry,
 
 		"3 links for fridge": func() LinkRegistry {
 			registry := NewLinkRegistry()
 			RegisterOn(registry, fridge{}, Self("/api/fridges", "Get this fridge"), Post("/api/fridges", "Create a new fridge"), Delete("/api/v1/fridges/{id}", "Delete a fridge"))
+
 			return registry
 		},
 
@@ -867,6 +865,7 @@ func BenchmarkInjectLinks(b *testing.B) {
 			RegisterOn(registry, vegetable{}, Self("/api/vegetables", "Get this vegetable"), Post("/api/vegetables", "Create a new vegetable"), Delete("/api/v1/vegetables/{id}", "Delete a vegetable"))
 			RegisterOn(registry, fruit{}, Self("/api/fruits", "Get this fruit"), Post("/api/fruits", "Create a new fruit"), Delete("/api/v1/fruits/{id}", "Delete a fruit"))
 			RegisterOn(registry, cake{}, Self("/api/cakes", "Get this cake"), Post("/api/cakes", "Create a new cake"), Delete("/api/v1/cakes/{id}", "Delete a cake"))
+
 			return registry
 		},
 	}

registry_test.go

@@ -1,9 +1,10 @@
 package gohateoas
 
 import (
-	"github.com/stretchr/testify/assert"
 	"net/http"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestGetTypeName_ReturnsNameOnTypeA(t *testing.T) {