auto-generated rust code fails to compile

[CrepeGoat]

system

• macbook air M1 2020
• macOS 14.5 Sonoma
• cargo --version -> cargo 1.81.0 (2dbb1af80 2024-08-20)
• rustup --version -> rustc 1.81.0 (eeb90cda1 2024-09-04)
• slint = "1.8.0"

code

build.rs

fn main() {
    slint_build::compile("ui/app-window.slint").expect("Slint build failed");
}

src/main.rs

// Prevent console window in addition to Slint window in Windows release builds when, e.g., starting the app via file manager. Ignored on other platforms.
#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]

slint::include_modules!();

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let ui = AppWindow::new()?;

    ui.run()?;

    Ok(())
}

ui/app-window.slint

import {  HorizontalBox } from "std-widgets.slint";

component DeltasList {
    in property <string> delta;
}

component Changelog inherits Rectangle {
    in-out property <int> count-files-changed;
    in-out property <[string]> changes_log: [];
    in-out property <int> selected: -2;
    callback selection-changed(/*new selection*/ int);
}

export component AppWindow inherits Window {
    in-out property <[string]> changes_log <=> log.changes_log;
    in-out property <int> count-files-changed <=> log.count-files-changed;
    in-out property <string> delta <=> deltas.delta;
    callback request-change-delta(string);
    callback request-diff-delta(string);

    function fill-diff-view() {
        if log.selected >= 0 && log.selected < changes_log.length {
            root.request-change-delta(changes_log[log.selected])
        } else if log.selected == -1 {
            root.request-diff-delta("channel name")
        } else {
            delta = "";
        }
    }

    HorizontalBox {
        log := Changelog {
            horizontal-stretch: 2;
            selection-changed => {
                fill-diff-view();
            }
        }

        deltas := DeltasList {
            horizontal-stretch: 3;
        }
    }
}

problem

running cargo build generates the error:

error[E0425]: cannot find value `tmp_root_1_changes_log` in this scope
   --> /.../target/debug/build/project-3091f44e836850bc/out/app-window.rs:711:66
    |
711 | ... (match & r#tmp_root_1_changes_log . clone () {
    |              ^^^^^^^^^^^^^^^^^^^^^^^^ not found in this scope

error[E0425]: cannot find value `tmp_log_3_selected` in this scope
   --> /.../target/debug/build/project-3091f44e836850bc/out/app-window.rs:713:47
    |
713 | ...   let index = (r#tmp_log_3_selected . clone ()) as usize ;
    |                    ^^^^^^^^^^^^^^^^^^^^ not found in this scope

For more information about this error, try `rustc --explain E0425`.
error: could not compile `project` (bin "project") due to 2 previous errors

this error seems to take place in the generated rust code.

working alternatives

• replace

  root.request-change-delta(changes_log[log.selected])

  with

  root.request-change-delta("")

• replace

  if log.selected >= 0 && log.selected < changes_log.length {
      root.request-change-delta(changes_log[log.selected])
  } else if log.selected == -1 {
      root.request-diff-delta("channel name")
  } else {
      delta = "";
  }

  with

  if log.selected >= 0 && log.selected < changes_log.length {
      root.request-change-delta(changes_log[log.selected])
  } else {
      root.request-diff-delta("channel name")
  }

expected behavior

either:

• compile, or
• emit a slint-contexted error referencing the slint user code, instead of a rust-contexted error referencing the auto-generated rust code