How to use Error method of js Package

Best K6 code snippet using js.Error

fs_js.go

Source:fs_js.go

...418	jsFS.Call(name, append(args, js.FuncOf(func(this js.Value, args []js.Value) interface{} {419		var res callResult420		if len(args) >= 1 { // on Node.js 8, fs.utimes calls the callback without any arguments421			if jsErr := args[0]; jsErr != js.Null() {422				res.err = mapJSError(jsErr)423			}424		}425		res.val = js.Undefined()426		if len(args) >= 2 {427			res.val = args[1]428		}429		c <- res430		return nil431	}))...)432	res := <-c433	return res.val, res.err434}435// checkPath checks that the path is not empty and that it contains no null characters.436func checkPath(path string) error {437	if path == "" {438		return EINVAL439	}440	for i := 0; i < len(path); i++ {441		if path[i] == '\x00' {442			return EINVAL443		}444	}445	return nil446}447func recoverErr(errPtr *error) {448	if err := recover(); err != nil {449		jsErr, ok := err.(js.Error)450		if !ok {451			panic(err)452		}453		*errPtr = mapJSError(jsErr.Value)454	}455}456// mapJSError maps an error given by Node.js to the appropriate Go error457func mapJSError(jsErr js.Value) error {458	errno, ok := errnoByCode[jsErr.Get("code").String()]459	if !ok {460		panic(jsErr)461	}462	return errnoErr(Errno(errno))463}...

roundtrip_js.go

Source:roundtrip_js.go

...128		return nil129	})130	defer success.Release()131	failure := js.FuncOf(func(this js.Value, args []js.Value) interface{} {132		err := fmt.Errorf("net/http: fetch() failed: %s", args[0].String())133		select {134		case errCh <- err:135		case <-req.Context().Done():136		}137		return nil138	})139	defer failure.Release()140	respPromise.Call("then", success, failure)141	select {142	case <-req.Context().Done():143		if ac != js.Undefined() {144			// Abort the Fetch request145			ac.Call("abort")146		}147		return nil, req.Context().Err()148	case resp := <-respCh:149		return resp, nil150	case err := <-errCh:151		return nil, err152	}153}154var errClosed = errors.New("net/http: reader is closed")155// useFakeNetwork is used to determine whether the request is made156// by a test and should be made to use the fake in-memory network.157func useFakeNetwork() bool {158	return len(os.Args) > 0 && strings.HasSuffix(os.Args[0], ".test")159}160// streamReader implements an io.ReadCloser wrapper for ReadableStream.161// See https://fetch.spec.whatwg.org/#readablestream for more information.162type streamReader struct {163	pending []byte164	stream  js.Value165	err     error // sticky read error166}167func (r *streamReader) Read(p []byte) (n int, err error) {168	if r.err != nil {169		return 0, r.err170	}171	if len(r.pending) == 0 {172		var (173			bCh   = make(chan []byte, 1)174			errCh = make(chan error, 1)175		)176		success := js.FuncOf(func(this js.Value, args []js.Value) interface{} {177			result := args[0]178			if result.Get("done").Bool() {179				errCh <- io.EOF180				return nil181			}182			value := make([]byte, result.Get("value").Get("byteLength").Int())183			a := js.TypedArrayOf(value)184			a.Call("set", result.Get("value"))185			a.Release()186			bCh <- value187			return nil188		})189		defer success.Release()190		failure := js.FuncOf(func(this js.Value, args []js.Value) interface{} {191			// Assumes it's a TypeError. See192			// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError193			// for more information on this type. See194			// https://streams.spec.whatwg.org/#byob-reader-read for the spec on195			// the read method.196			errCh <- errors.New(args[0].Get("message").String())197			return nil198		})199		defer failure.Release()200		r.stream.Call("read").Call("then", success, failure)201		select {202		case b := <-bCh:203			r.pending = b204		case err := <-errCh:205			r.err = err206			return 0, err207		}208	}209	n = copy(p, r.pending)210	r.pending = r.pending[n:]211	return n, nil212}213func (r *streamReader) Close() error {214	// This ignores any error returned from cancel method. So far, I did not encounter any concrete215	// situation where reporting the error is meaningful. Most users ignore error from resp.Body.Close().216	// If there's a need to report error here, it can be implemented and tested when that need comes up.217	r.stream.Call("cancel")218	if r.err == nil {219		r.err = errClosed220	}221	return nil222}223// arrayReader implements an io.ReadCloser wrapper for ArrayBuffer.224// https://developer.mozilla.org/en-US/docs/Web/API/Body/arrayBuffer.225type arrayReader struct {226	arrayPromise js.Value227	pending      []byte228	read         bool229	err          error // sticky read error230}231func (r *arrayReader) Read(p []byte) (n int, err error) {232	if r.err != nil {233		return 0, r.err234	}235	if !r.read {236		r.read = true237		var (238			bCh   = make(chan []byte, 1)239			errCh = make(chan error, 1)240		)241		success := js.FuncOf(func(this js.Value, args []js.Value) interface{} {242			// Wrap the input ArrayBuffer with a Uint8Array243			uint8arrayWrapper := js.Global().Get("Uint8Array").New(args[0])244			value := make([]byte, uint8arrayWrapper.Get("byteLength").Int())245			a := js.TypedArrayOf(value)246			a.Call("set", uint8arrayWrapper)247			a.Release()248			bCh <- value249			return nil250		})251		defer success.Release()252		failure := js.FuncOf(func(this js.Value, args []js.Value) interface{} {253			// Assumes it's a TypeError. See254			// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError255			// for more information on this type.256			// See https://fetch.spec.whatwg.org/#concept-body-consume-body for reasons this might error.257			errCh <- errors.New(args[0].Get("message").String())258			return nil259		})260		defer failure.Release()261		r.arrayPromise.Call("then", success, failure)262		select {263		case b := <-bCh:264			r.pending = b265		case err := <-errCh:266			return 0, err267		}268	}...

Error

Using AI Code Generation

1import (2func main() {3	err := js.Global().Get("Error").New("Error message")4	fmt.Println(err.Get("message").String())5	fmt.Println(err.Get("name").String())6	fmt.Println(err.Get("stack").String())7}8import (9func main() {10	err := js.Global().Get("Error").New("Error message")11	fmt.Println(err.Get("message").String())12	fmt.Println(err.Get("name").String())13	fmt.Println(err.Get("stack").String())14}15import (16func main() {17	err := js.Global().Get("Error").New("Error message")18	fmt.Println(err.Get("message").String())19	fmt.Println(err.Get("name").String())20	fmt.Println(err.Get("stack").String())21}22import (23func main() {24	err := js.Global().Get("Error").New("Error message")25	fmt.Println(err.Get("message").String())26	fmt.Println(err.Get("name").String())27	fmt.Println(err.Get("stack").String())28}29import (

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