Add linter

.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 # extensively used in the test files
+    - 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

README.md

@@ -65,8 +65,10 @@ func handleGet(c *gin.Context) {
 ## 🚀 Development
 
 1. Clone the repository
-2. Run `make t` to run unit tests
-3. Run `make fmt` to format code
+2. Run `make tools` to install necessary tools
+3. Run `make t` to run unit tests
+4. Run `make fmt` to format code
+4. Run `make lint` to lint your code
 
 You can run `make` to see a list of useful commands.
 

errors.go

@@ -9,8 +9,10 @@ const defaultCode = http.StatusInternalServerError
 
 var DefaultErrorRegistry = NewErrorRegistry()
 
-type internalHandler func(err error) (int, any)
-type internalStringHandler func(err string) (int, any)
+type (
+	internalHandler       func(err error) (int, any)
+	internalStringHandler func(err string) (int, any)
+)
 
 // CustomErrorHandler is the template for unexported errors. For example binding.SliceValidationError
 // or uuid.invalidLengthError
@@ -64,13 +66,17 @@ func (e *ErrorRegistry) SetDefaultResponse(code int, response any) {
 }
 
 // NewErrorResponse Returns an error response using the DefaultErrorRegistry. If no specific handler could be found,
-// it will return the defaults.
+// it will return the defaults. It returns an HTTP status code and a response object.
+//
+//nolint:gocritic // Unnamed return arguments are described
 func NewErrorResponse(err error) (int, any) {
 	return NewErrorResponseFrom(DefaultErrorRegistry, err)
 }
 
 // NewErrorResponseFrom Returns an error response using the given registry. If no specific handler could be found,
-// it will return the defaults.
+// it will return the defaults. It returns an HTTP status code and a response object.
+//
+//nolint:gocritic // Unnamed return arguments are described
 func NewErrorResponseFrom(registry *ErrorRegistry, err error) (int, any) {
 	errorType := fmt.Sprintf("%T", err)
 
@@ -98,6 +104,7 @@ func RegisterErrorHandlerOn[E error, R any](registry *ErrorRegistry, handler Err
 	// be available in the closure when it is called. Check out TestErrorResponseFrom_ReturnsErrorBInInterface for an example.
 	registry.handlers[errorType] = func(err error) (int, any) {
 		// We can safely cast it here, because we know it's the right type.
+		//nolint:errorlint // Not relevant, we're casting anyway
 		return handler(err.(E))
 	}
 }

errors_test.go

@@ -2,9 +2,10 @@ package ginerr
 
 import (
 	"errors"
-	"github.com/stretchr/testify/assert"
 	"net/http"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestDefaultErrorGenerator_IsSet(t *testing.T) {
@@ -18,37 +19,38 @@ func TestDefaultErrorGenerator_IsSet(t *testing.T) {
 
 // Register functions are tested through NewErrorResponse[E error]
 
-type ErrorA struct {
+type aError struct {
 	message string
 }
 
-func (e ErrorA) Error() string {
+func (e aError) Error() string {
 	return e.message
 }
 
-type ErrorB struct {
+type bError struct {
 	message string
 }
 
-func (e ErrorB) Error() string {
+func (e bError) Error() string {
 	return e.message
 }
 
 // The top ones are not parallel because it uses the DefaultErrorRegistry, which is a global
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponse_UsesDefaultErrorRegistry(t *testing.T) {
 	// Arrange
 	expectedResponse := Response{
 		Errors: map[string]any{"error": "It was the man with one hand!"},
 	}
 
-	callback := func(err *ErrorA) (int, Response) {
+	callback := func(err *aError) (int, Response) {
 		return 634, Response{
 			Errors: map[string]any{"error": err.Error()},
 		}
 	}
 
-	err := &ErrorA{message: "It was the man with one hand!"}
+	err := &aError{message: "It was the man with one hand!"}
 
 	RegisterErrorHandler(callback)
 
@@ -60,6 +62,7 @@ func TestErrorResponse_UsesDefaultErrorRegistry(t *testing.T) {
 	assert.Equal(t, expectedResponse, response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponse_UsesDefaultErrorRegistryForStrings(t *testing.T) {
 	// Arrange
 	expectedResponse := Response{
@@ -84,6 +87,7 @@ func TestErrorResponse_UsesDefaultErrorRegistryForStrings(t *testing.T) {
 	assert.Equal(t, expectedResponse, response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponse_UsesDefaultErrorRegistryForCustomTypes(t *testing.T) {
 	// Arrange
 	expectedResponse := Response{
@@ -108,6 +112,7 @@ func TestErrorResponse_UsesDefaultErrorRegistryForCustomTypes(t *testing.T) {
 	assert.Equal(t, expectedResponse, response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponseFrom_ReturnsGenericErrorOnNotFound(t *testing.T) {
 	t.Parallel()
 	// Arrange
@@ -123,6 +128,7 @@ func TestErrorResponseFrom_ReturnsGenericErrorOnNotFound(t *testing.T) {
 	assert.Equal(t, "test", response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponseFrom_ReturnsErrorA(t *testing.T) {
 	t.Parallel()
 	// Arrange
@@ -131,11 +137,11 @@ func TestErrorResponseFrom_ReturnsErrorA(t *testing.T) {
 		Errors: map[string]any{"error": "It was the man with one hand!"},
 	}
 
-	callback := func(err *ErrorA) (int, Response) {
+	callback := func(err *aError) (int, Response) {
 		return 500, expectedResponse
 	}
 
-	err := &ErrorA{message: "It was the man with one hand!"}
+	err := &aError{message: "It was the man with one hand!"}
 
 	RegisterErrorHandlerOn(registry, callback)
 
@@ -147,6 +153,7 @@ func TestErrorResponseFrom_ReturnsErrorA(t *testing.T) {
 	assert.Equal(t, expectedResponse, response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponseFrom_ReturnsErrorB(t *testing.T) {
 	t.Parallel()
 	// Arrange
@@ -155,11 +162,11 @@ func TestErrorResponseFrom_ReturnsErrorB(t *testing.T) {
 		Errors: map[string]any{"error": "It was the man with one hand!"},
 	}
 
-	callback := func(err *ErrorB) (int, Response) {
+	callback := func(err *bError) (int, Response) {
 		return 500, expectedResponse
 	}
 
-	err := &ErrorB{message: "It was the man with one hand!"}
+	err := &bError{message: "It was the man with one hand!"}
 
 	RegisterErrorHandlerOn(registry, callback)
 
@@ -171,6 +178,7 @@ func TestErrorResponseFrom_ReturnsErrorB(t *testing.T) {
 	assert.Equal(t, expectedResponse, response)
 }
 
+//nolint:paralleltest // Because of global state
 func TestErrorResponseFrom_ReturnsErrorBInInterface(t *testing.T) {
 	t.Parallel()
 	// Arrange
@@ -179,11 +187,11 @@ func TestErrorResponseFrom_ReturnsErrorBInInterface(t *testing.T) {
 		Errors: map[string]any{"error": "It was the man with one hand!"},
 	}
 
-	callback := func(err *ErrorB) (int, Response) {
+	callback := func(err *bError) (int, Response) {
 		return 500, expectedResponse
 	}
 
-	var err error = &ErrorB{message: "It was the man with one hand!"}
+	var err error = &bError{message: "It was the man with one hand!"}
 
 	RegisterErrorHandlerOn(registry, callback)
 
@@ -196,6 +204,7 @@ func TestErrorResponseFrom_ReturnsErrorBInInterface(t *testing.T) {
 }
 
 func TestErrorResponseFrom_ReturnsErrorStrings(t *testing.T) {
+	t.Parallel()
 	tests := []string{
 		"Something went completely wrong!",
 		"Record not found",
@@ -204,6 +213,7 @@ func TestErrorResponseFrom_ReturnsErrorStrings(t *testing.T) {
 	for _, errorString := range tests {
 		errorString := errorString
 		t.Run(errorString, func(t *testing.T) {
+			t.Parallel()
 			// Arrange
 			registry := NewErrorRegistry()
 			expectedResponse := Response{
@@ -231,6 +241,7 @@ func TestErrorResponseFrom_ReturnsErrorStrings(t *testing.T) {
 }
 
 func TestErrorResponseFrom_CanConfigureMultipleErrorStrings(t *testing.T) {
+	t.Parallel()
 	// Arrange
 	registry := NewErrorRegistry()
 
@@ -258,6 +269,7 @@ func TestErrorResponseFrom_CanConfigureMultipleErrorStrings(t *testing.T) {
 }
 
 func TestErrorResponseFrom_ReturnsCustomErrorHandlers(t *testing.T) {
+	t.Parallel()
 	tests := []string{
 		"Something went completely wrong!",
 		"Record not found",
@@ -266,6 +278,7 @@ func TestErrorResponseFrom_ReturnsCustomErrorHandlers(t *testing.T) {
 	for _, errorString := range tests {
 		errorString := errorString
 		t.Run(errorString, func(t *testing.T) {
+			t.Parallel()
 			// Arrange
 			registry := NewErrorRegistry()
 			expectedResponse := Response{
@@ -298,7 +311,7 @@ func TestErrorResponseFrom_ReturnsGenericErrorOnTypeNotFound(t *testing.T) {
 	registry := NewErrorRegistry()
 
 	// Act
-	code, response := NewErrorResponseFrom(registry, &ErrorB{})
+	code, response := NewErrorResponseFrom(registry, &bError{})
 
 	// Assert
 	assert.Equal(t, http.StatusInternalServerError, code)

examples_test.go

@@ -6,8 +6,7 @@ type Response struct {
 	Errors map[string]any `json:"errors,omitempty"`
 }
 
-type MyError struct {
-}
+type MyError struct{}
 
 func (m MyError) Error() string {
 	return "Something went wrong!"

v2/errors.go

@@ -10,8 +10,10 @@ const defaultCode = http.StatusInternalServerError
 
 var DefaultErrorRegistry = NewErrorRegistry()
 
-type internalHandler func(ctx context.Context, err error) (int, any)
-type internalStringHandler func(ctx context.Context, err string) (int, any)
+type (
+	internalHandler       func(ctx context.Context, err error) (int, any)
+	internalStringHandler func(ctx context.Context, err string) (int, any)
+)
 
 func NewErrorRegistry() *ErrorRegistry {
 	registry := &ErrorRegistry{

v2/errors_test.go

@@ -3,9 +3,10 @@ package ginerr
 import (
 	"context"
 	"errors"
-	"github.com/stretchr/testify/assert"
 	"net/http"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 // Register functions are tested through NewErrorResponse[E error]

v2/examples_test.go

@@ -9,8 +9,7 @@ type Response struct {
 	Errors map[string]any `json:"errors,omitempty"`
 }
 
-type MyError struct {
-}
+type MyError struct{}
 
 func (m MyError) Error() string {
 	return "Something went wrong!"