package main

import "errors"

func shouldDeclareErrInSignature() error { // want "return signature should use named error parameter err"
	// Should use variable declared in signature. We don't need to report this
	// as if the variable is declared in the signature, a redeclaration causes
	// a compile error.
	var err error

	err = nil
	if err != nil {
		return err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	return nil // want "does not return 'err'"
}

func doesDeclareErrInSignature() (err error) {
	err = nil
	if err != nil {
		return err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	return nil // want "does not return 'err'"
}

func returnedErrorMustMatchDeferErrorName() (err error) {
	err = nil
	if err != nil {
		return err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	err2 := errors.New("returned error")

	return err2 // want "does not return 'err'"
}

func deferUsesUnconventionalErrName() error { // want "return signature should use named error parameter anErr"
	var anErr error

	anErr = nil
	if anErr != nil {
		return anErr
	}

	defer func() {
		anErr = errors.New("defer error")
	}()

	return anErr
}


func multipleReturnValuesString() (string, error) { // want "return signature should use named error parameter err"
	var err error = nil
	if err != nil {
		return "", err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	return "ret", err
}

type AStruct struct {}

func multipleReturnValuesStructBool() (*AStruct, bool, error) { // want "return signature should use named error parameter err"
	var err error = nil
	if err != nil {
		return nil, false, err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	return &AStruct{}, true, err
}

func good() (err error) {
	err = nil
	if err != nil {
		return err
	}

	defer func() {
		err = errors.New("defer error")
	}()

	return err
}

func noErrorInReturn() string {
	return "test"
}