vectorcraft/crates/testkit/src/lib.rs

//! VectorCraft test helpers.
//!
//! - [`fixtures`]: sessions and documents in known states (empty, single/multi selection, a "rich"
//!   document touching most node kinds), plus a [`fixtures::DocBuilder`] for building documents
//!   directly (render tests).
//! - [`strategies`]: proptest strategies for geometry and for engine command sequences ([`strategies::Op`]), and
//!   junk-parameter generators for fuzzing the command registry.
//! - [`invariants`]: structural checks for documents and sessions, and round-trip checks
//!   (`.vectorcraft`, SVG, `document.inspect`).
//! - [`raster`]: rendering helpers and image comparison with a perceptual tolerance.
//! - [`geom`]: geometry assertions (approximate equality, curve sampling, Hausdorff distance).
//! - [`pdf`]: hand-written PDF files (page boxes, colour spaces, encryption) for import tests.
//!
//! This crate may only be used as a dev-dependency (enforced by `cargo xtask layers`).
// Test support only (a dev-dependency of every crate that uses it): a failed setup or assertion
// must panic, like `assert!`, so the shipped-code ban on panicking (AGENTS.md › Robustness) doesn't
// apply here.
#![allow(clippy::unwrap_used, clippy::expect_used, clippy::panic)]
#![forbid(unsafe_code)]

pub mod fixtures;
pub mod geom;
pub mod invariants;
pub mod pdf;
pub mod raster;
pub mod strategies;

pub use serde_json::{Value, json};
pub use vectorcraft_engine::{Session, doc::NodeId};
/// Re-exports so dependents without direct dependencies (e.g. app test crates) can use them.
pub use {vectorcraft_doc as doc, vectorcraft_format as format, vectorcraft_render as render, vectorcraft_svg as svg};

/// A per-process temporary directory for test output (created on first use).
pub fn temp_dir(tag: &str) -> std::path::PathBuf {
    let dir = std::env::temp_dir().join(format!("vectorcraft-testkit-{tag}-{}", std::process::id()));
    std::fs::create_dir_all(&dir).expect("create temp dir");
    dir
}

thread_local! {
    static QUIET: std::cell::Cell<bool> = const { std::cell::Cell::new(false) };
}

/// Run `f`, catching a panic without printing it (other threads' panics still print). Returns the
/// panic message on panic.
pub fn catch_quiet<T>(f: impl FnOnce() -> T) -> Result<T, String> {
    static HOOK: std::sync::Once = std::sync::Once::new();
    HOOK.call_once(|| {
        let prev = std::panic::take_hook();
        std::panic::set_hook(Box::new(move |info| {
            if !QUIET.with(|q| q.get()) {
                prev(info);
            }
        }));
    });
    QUIET.with(|q| q.set(true));
    let r = std::panic::catch_unwind(std::panic::AssertUnwindSafe(f));
    QUIET.with(|q| q.set(false));
    r.map_err(|p| p.downcast_ref::<String>().cloned().or_else(|| p.downcast_ref::<&str>().map(|s| s.to_string())).unwrap_or_else(|| "panic".into()))
}