Ask user to install platform when it hasn't been installed yet

platformio/commands/run.py

@@ -59,7 +59,10 @@ def cli(environment, target, upload_port):
 
         telemetry.on_run_environment(config.items(section), envtargets)
 
-        p = PlatformFactory().newPlatform(config.get(section, "platform"))
+        if (platform not in PlatformFactory.get_platforms(installed=True) and
+                click.confirm("The platform '%s' has not been installed yet. "
+                              "Would you like to install it now?" % platform)):
+            ctx.invoke(cmd_install, platforms=[platform])
         result = p.run(variables, envtargets)
         secho(result['out'], fg="green")
         secho(result['err'],

platformio/commands/show.py

@@ -18,7 +18,11 @@ def cli(platform):
         installed=True).keys()
 
     if platform not in installed_platforms:
-        raise PlatformNotInstalledYet(platform)
+        if click.confirm("The platform '%s' has not been installed yet. "
+                         "Would you like to install it now?" % platform):
+            ctx.invoke(cmd_install, platforms=[platform])
+        else:
+            raise PlatformNotInstalledYet(platform)
 
     p = PlatformFactory().newPlatform(platform)
     echo("{name:<20} - {info}".format(name=style(p.get_name(), fg="cyan"),