Add auto toString for various APIs (#1033)

libs/core/basic.cpp

@@ -33,6 +33,7 @@ namespace basic {
     //% async
     //% blockId=device_print_message
     //% parts="ledmatrix"
+    //% text.shadowOptions.toString=true
     void showString(String text, int interval = 150) {
       if (interval <= 0)
         interval = 1;

libs/core/serial.cpp

@@ -103,6 +103,7 @@ namespace serial {
     //% help=serial/write-string
     //% weight=87 blockGap=8
     //% blockId=serial_writestring block="serial|write string %text"
+    //% text.shadowOptions.toString=true
     void writeString(String text) {
       if (!text) return;
 

libs/core/serial.ts

@@ -11,6 +11,7 @@ namespace serial {
     //% weight=90
     //% help=serial/write-line blockGap=8
     //% blockId=serial_writeline block="serial|write line %text"
+    //% text.shadowOptions.toString=true
     export function writeLine(text: string): void {
         if (!text) text = "";
         // pad data to the 32 byte boundary

libs/core/shims.d.ts

@@ -153,7 +153,8 @@ declare namespace basic {
     //% block="show|string %text"
     //% async
     //% blockId=device_print_message
-    //% parts="ledmatrix" interval.defl=150 shim=basic::showString
+    //% parts="ledmatrix"
+    //% text.shadowOptions.toString=true interval.defl=150 shim=basic::showString
     function showString(text: string, interval?: int32): void;
 
     /**
@@ -791,7 +792,8 @@ declare namespace serial {
      */
     //% help=serial/write-string
     //% weight=87 blockGap=8
-    //% blockId=serial_writestring block="serial|write string %text" shim=serial::writeString
+    //% blockId=serial_writestring block="serial|write string %text"
+    //% text.shadowOptions.toString=true shim=serial::writeString
     function writeString(text: string): void;
 
     /**

libs/radio/radio.cpp

@@ -244,6 +244,7 @@ namespace radio {
     //% help=radio/send-string
     //% weight=58
     //% blockId=radio_datagram_send_string block="radio send string %msg"
+    //% msg.shadowOptions.toString=true
     void sendString(String msg) {
         if (radioEnable() != MICROBIT_OK || NULL == msg) return;
 

libs/radio/shims.d.ts

@@ -30,7 +30,8 @@ declare namespace radio {
      */
     //% help=radio/send-string
     //% weight=58
-    //% blockId=radio_datagram_send_string block="radio send string %msg" shim=radio::sendString
+    //% blockId=radio_datagram_send_string block="radio send string %msg"
+    //% msg.shadowOptions.toString=true shim=radio::sendString
     function sendString(msg: string): void;
 
     /**