#!/usr/bin/env nomsu -V2
use "core"
use "compatibility/compatibility.nom"

upgrade %tree to "2" as:
    unless (%tree is "Action" syntax tree): return
    if (all[%tree.stub is "if % % else %", not (%tree.3 is "Var" syntax tree), not (%tree.5 is "Var" syntax tree)]):
        %true_body <- (%tree.3 upgraded from "1.2")
        unless (%true_body is "Block" syntax tree):
            %true_body <- (=lua "Block(\%true_body.source, \%true_body)")
        %false_body <- (%tree.5 upgraded from "1.2")
        unless (%false_body is "Block" syntax tree):
            %false_body <- (=lua "Block(\%false_body.source, \%false_body)")
        return (..)
            \(if %cond %true_body else %false_body)
            ..with vars {..}
                cond:%tree.2 upgraded from "1.2", true_body:%true_body, false_body:%false_body
    
    %need_blocks <- [..]
        "if % %", "unless % %", "for % in % %", "for % = % in % %", "repeat while % %"
        "repeat % times %", "repeat %", "repeat until % %", "for % in % to % by % %",
        "for % in % to % via % %", "for % in % to % %", "for % % in % %", "do %"
        "for % in recursive % %", "test %", "with % %", "result of %"
    for %n in %need_blocks:
        if ((%tree.stub is %n) and (not ((last in %tree) is "Var" syntax tree))):
            %bits <- (((% upgraded from "1.2") if (% is syntax tree) else %) for % in %tree)
            unless ((last in %bits) is "Block" syntax tree):
                %body <- (last in %bits)
                %bits.(length of %bits) <- (=lua "Block(\%body.source, \%body)")
            return (=lua "Action(\%tree.source, unpack(\%bits))")