016 host line local shadows tor input

// Pins that a tor input is a BINDING, not a token the emitter may rewrite by
// text — and that a host-line local sharing its name cannot reach into the proc
// body at all.
//
// `unrelatedHelper` is never called from `describe`'s chain and its `const
// count` is function-local, so nothing about it is in scope where the proc body
// runs. The only place the two names meet is the emitter.
//
// The string literals are the instrument. A substitution that lands on code
// fails loudly in Zig; one that lands inside a literal produces a program that
// compiles, runs, and prints a corrupted sentence — so the guarantee is only
// observable on stdout, which is why this is a MUST_RUN and not a MUST_ERROR.
//
// Control: rename the helper's local and nothing else, and the sentence comes
// back clean. That is the whole difference this test guards.

const std = @import("std");

fn unrelatedHelper() u32 {
    const count = 7;
    return count;
}

~import std/io

~pub tor describe { count: u32 } -> string

~proc describe|zig {
    _ = unrelatedHelper();
    if (count == 0) {
        return "a count of zero";
    }
    return "a count above zero";
}

~describe(count: 3): text |> std/io:print.ln("{{ text:s }}")