Make lang-test0 work

libs/lang-test0/lang-test0.ts

@@ -1,3 +1,8 @@
+//
+// Note that this is supposed to run from command line.
+// Do not use anything besides basic.pause, control.inBackground, console.log
+//
+
 //% shim=ksrt::panic
 function panic(code2: number): void { }
 
@@ -79,15 +84,11 @@ var unusedInit = incrXyz();
 
 assert(xyz == 13, "init2")
 
+
 testClass()
 
-basic.showLeds(`
-    # # . # #
-    # # . # #
-    . . # . .
-    # . . . #
-    . # # # .
-    `)
+basic.showNumber(1)
+
 
 console.log("ALL TESTS OK")