improve: support js,wasm (#683)

Author: shynome

transport.go

@@ -25,7 +25,7 @@ func createTransport(localAddr net.Addr) *http.Transport {
 	}
 	return &http.Transport{
 		Proxy:                 http.ProxyFromEnvironment,
-		DialContext:           dialer.DialContext,
+		DialContext:           transportDialContext(dialer),
 		ForceAttemptHTTP2:     true,
 		MaxIdleConns:          100,
 		IdleConnTimeout:       90 * time.Second,

transport_js.go

@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build js && wasm
+// +build js,wasm
+
+package resty
+
+import (
+	"context"
+	"net"
+)
+
+func transportDialContext(dialer *net.Dialer) func(context.Context, string, string) (net.Conn, error) {
+	return nil
+}

transport_other.go

@@ -0,0 +1,17 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !(js && wasm)
+// +build !js !wasm
+
+package resty
+
+import (
+	"context"
+	"net"
+)
+
+func transportDialContext(dialer *net.Dialer) func(context.Context, string, string) (net.Conn, error) {
+	return dialer.DialContext
+}