tishlang 2.0.3

//! Full-stack integration tests: run .tish files with interpreter or each backend and compare
//! stdout to static expected files (e.g. `fn_any.tish.expected`).
//!
//! - Run: `cargo test -p tishlang` (or `cargo nextest run -p tishlang`).
//! - Generate/update expected files: `REGENERATE_EXPECTED=1 cargo test -p tishlangtest_mvp_programs_interpreter`
//!   then commit the new/updated `tests/core/*.tish.expected` files.
//! - Compiled outputs are cached under `target/integration_compile_cache/` per backend.
//!   MVP native tests use `native_many/<hash>/` plus one batched nested Cargo build.

use std::collections::hash_map::DefaultHasher;
use std::ffi::OsString;
use std::hash::{Hash, Hasher};
use std::io::Read;
use std::path::{Path, PathBuf};
use std::process::Command;

use rayon::prelude::*;
use tishlang_native::compile_many_to_native;

fn workspace_root() -> PathBuf {
    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
        .join("..")
        .join("..")
}

fn core_dir() -> PathBuf {
    workspace_root().join("tests").join("core")
}

/// Path to the static expected stdout for a .tish file (e.g. fn_any.tish -> fn_any.tish.expected).
fn expected_path(path: &Path) -> PathBuf {
    path.with_file_name(format!(
        "{}.expected",
        path.file_name().unwrap().to_string_lossy()
    ))
}

/// Read static expected stdout for a test file. Returns None if the file does not exist.
fn get_expected(path: &Path) -> Option<String> {
    let p = expected_path(path);
    std::fs::read_to_string(&p).ok()
}

fn target_dir() -> PathBuf {
    std::env::var("CARGO_TARGET_DIR")
        .map(PathBuf::from)
        .unwrap_or_else(|_| workspace_root().join("target"))
}

/// Cache dir for tish build outputs (under target/ so CI rust-cache restores it).
fn integration_compile_cache_dir() -> PathBuf {
    target_dir().join("integration_compile_cache")
}

/// Match `tish build` with no `--feature`: link every capability compiled into this `tish` binary.
fn native_build_features_for_integration_test() -> Vec<String> {
    let mut v: Vec<String> = tishlang_vm::all_compiled_capabilities()
        .into_iter()
        .collect();
    v.sort();
    v
}

fn combined_mvp_native_inputs_hash(paths: &[PathBuf]) -> u64 {
    let mut h = DefaultHasher::new();
    let feats = native_build_features_for_integration_test();
    feats.len().hash(&mut h);
    for f in &feats {
        f.hash(&mut h);
    }
    paths.len().hash(&mut h);
    for p in paths {
        p.file_name()
            .unwrap_or_default()
            .to_string_lossy()
            .hash(&mut h);
        file_content_hash(p).hash(&mut h);
    }
    // Native batch cache must invalidate when the emitter or `value_call` changes — not only
    // when `.tish` sources change; otherwise CI/rust-cache can keep stale nested binaries.
    let codegen_rs = workspace_root().join("crates/tish_compile/src/codegen.rs");
    if codegen_rs.is_file() {
        file_content_hash(&codegen_rs).hash(&mut h);
    }
    let value_rs = workspace_root().join("crates/tish_core/src/value.rs");
    if value_rs.is_file() {
        file_content_hash(&value_rs).hash(&mut h);
    }
    // Inference (struct/param/return typing — M1/M4/M5) also drives native emission, so the
    // native batch cache must invalidate when it changes too.
    let infer_rs = workspace_root().join("crates/tish_compile/src/infer.rs");
    if infer_rs.is_file() {
        file_content_hash(&infer_rs).hash(&mut h);
    }
    h.finish()
}

fn mvp_native_batch_cache_dir(combined: u64) -> PathBuf {
    integration_compile_cache_dir()
        .join("native_many")
        .join(format!("{:016x}", combined))
}

/// Restores the previous process env when dropped (for `TISH_FAST_NATIVE_BUILD` in batch tests).
struct EnvVarGuard {
    key: &'static str,
    previous: Option<std::ffi::OsString>,
}

impl EnvVarGuard {
    fn set(key: &'static str, value: &str) -> Self {
        let previous = std::env::var_os(key);
        std::env::set_var(key, value);
        Self { key, previous }
    }
}

impl Drop for EnvVarGuard {
    fn drop(&mut self) {
        match &self.previous {
            None => std::env::remove_var(self.key),
            Some(v) => std::env::set_var(self.key, v),
        }
    }
}

fn file_content_hash(path: &Path) -> u64 {
    let mut f = std::fs::File::open(path).expect("open file for hash");
    let mut content = Vec::new();
    f.read_to_end(&mut content).expect("read file for hash");
    let mut h = DefaultHasher::new();
    path.to_string_lossy().hash(&mut h);
    content.hash(&mut h);
    h.finish()
}

/// Compile a .tish file with the given backend, using a persistent cache so we only run
/// `tish build` when the file or backend changed. Returns path to the compiled artifact
/// (binary, .js, or .wasm) in a temp dir; caller may run it and then delete it.
///
/// Cache is keyed by backend (native, cranelift, js, wasi) so e.g. cranelift and wasi
/// compiles of the same file do not overwrite each other: .../cranelift/<stem>_<hash> vs .../wasi/<stem>_<hash>.wasm.
///
/// The artifact **basename** must be unique per `(stem, hash, backend)`: nested `tish build`
/// uses it as the Cargo binary name under the workspace `target/release/`. If native and
/// cranelift both used `strict_equality_<hash>`, parallel `cargo nextest` could run those
/// tests concurrently and corrupt the same `target/release/...` output (Linux: ETXTBSY when
/// executing a binary still being written).
fn compile_cached(bin: &Path, path: &Path, backend: &str) -> PathBuf {
    let stem = path.file_stem().unwrap().to_string_lossy();
    // The cache must invalidate when the COMPILER changes, not only the `.tish` source: cranelift/wasi
    // (and native) bake the VM/codegen/runtime into the artifact, so a stale cached binary built before
    // a VM fix would silently use old behaviour. The `tish` binary's mtime is the precise signal — any
    // VM/compiler/runtime/codegen source edit rebuilds it. Mix it into the key alongside the file hash.
    let bin_stamp = std::fs::metadata(bin)
        .and_then(|m| m.modified())
        .ok()
        .and_then(|t| t.duration_since(std::time::UNIX_EPOCH).ok())
        .map(|d| d.as_nanos() as u64)
        .unwrap_or(0);
    let hash = {
        let mut h = DefaultHasher::new();
        file_content_hash(path).hash(&mut h);
        bin_stamp.hash(&mut h);
        h.finish()
    };
    let hash8 = &format!("{:016x}", hash)[..8];
    let cache_base = integration_compile_cache_dir().join(backend);
    let _ = std::fs::create_dir_all(&cache_base);
    // Include `backend` in the leaf name so nested cargo bin names never collide across backends.
    let leaf = format!("{}__{}__{}", stem, backend, hash8);

    let (artifact_path, compile_args): (PathBuf, Vec<OsString>) = match backend {
        "native" => {
            let ext = if cfg!(target_os = "windows") {
                ".exe"
            } else {
                ""
            };
            let cached = cache_base.join(format!("{}{}", leaf, ext));
            let args = vec![
                OsString::from("build"),
                OsString::from(path),
                OsString::from("-o"),
                OsString::from(&cached),
            ];
            (cached, args)
        }
        "cranelift" => {
            let ext = if cfg!(target_os = "windows") {
                ".exe"
            } else {
                ""
            };
            let cached = cache_base.join(format!("{}{}", leaf, ext));
            let args = vec![
                OsString::from("build"),
                OsString::from(path),
                OsString::from("-o"),
                OsString::from(&cached),
                OsString::from("--native-backend"),
                OsString::from("cranelift"),
            ];
            (cached, args)
        }
        "js" => {
            let cached = cache_base.join(format!("{}.js", leaf));
            let args = vec![
                OsString::from("build"),
                OsString::from(path),
                OsString::from("--target"),
                OsString::from("js"),
                OsString::from("-o"),
                OsString::from(&cached),
            ];
            (cached, args)
        }
        "wasi" => {
            let out_base = cache_base.join(&leaf);
            let artifact = out_base.with_extension("wasm");
            let args = vec![
                OsString::from("build"),
                OsString::from(path),
                OsString::from("-o"),
                OsString::from(&out_base),
                OsString::from("--target"),
                OsString::from("wasi"),
            ];
            (artifact, args)
        }
        _ => panic!("unknown backend {}", backend),
    };

    if !artifact_path.exists() {
        let out = Command::new(bin)
            .args(compile_args)
            .current_dir(workspace_root())
            .output()
            .expect("run tish build");
        assert!(
            out.status.success(),
            "Compile failed for {} ({}): {}",
            path.display(),
            backend,
            String::from_utf8_lossy(&out.stderr)
        );
    }

    // Copy to temp so caller can run and delete without touching cache.
    let ext = artifact_path
        .extension()
        .map(|e| e.to_string_lossy().to_string())
        .unwrap_or_default();
    let temp_dest =
        std::env::temp_dir().join(format!("tish_cached_{}_{}_{}", backend, stem, hash8));
    let temp_dest = if ext.is_empty() {
        temp_dest
    } else {
        temp_dest.with_extension(ext)
    };
    std::fs::copy(&artifact_path, &temp_dest).expect("copy cached artifact to temp");
    temp_dest
}

/// Path to the tish CLI binary. When running under cargo-llvm-cov, the build goes to
/// target/llvm-cov-target and CARGO_TARGET_DIR may not be set for the test process.
fn tish_bin() -> PathBuf {
    let bin_name = if cfg!(target_os = "windows") {
        "tish.exe"
    } else {
        "tish"
    };
    let default = target_dir().join("debug").join(bin_name);
    if default.exists() {
        return default;
    }
    let llvm_cov = workspace_root()
        .join("target")
        .join("llvm-cov-target")
        .join("debug")
        .join(bin_name);
    if llvm_cov.exists() {
        return llvm_cov;
    }
    default
}

/// tish -V and --version print the version.
#[test]
fn test_tish_version_flag() {
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found. Run `cargo build -p tishlang` first."
    );
    let out = Command::new(&bin).arg("-V").output().expect("run tish -V");
    assert!(
        out.status.success(),
        "tish -V failed: {}",
        String::from_utf8_lossy(&out.stderr)
    );
    let stdout = String::from_utf8_lossy(&out.stdout);
    assert!(
        stdout.contains(env!("CARGO_PKG_VERSION")),
        "tish -V should print version {}; got: {}",
        env!("CARGO_PKG_VERSION"),
        stdout
    );
    let out2 = Command::new(&bin)
        .arg("--version")
        .output()
        .expect("run tish --version");
    assert!(out2.status.success());
    let stdout2 = String::from_utf8_lossy(&out2.stdout);
    assert!(
        stdout2.contains(env!("CARGO_PKG_VERSION")),
        "tish --version should print version"
    );
}

/// Parse async-await example (validates async fn parsing).
#[test]
fn test_async_await_parse() {
    let path = workspace_root()
        .join("examples")
        .join("async-await")
        .join("src")
        .join("main.tish");
    if path.exists() {
        let source = std::fs::read_to_string(&path).unwrap();
        let result = tishlang_parser::parse(&source);
        assert!(
            result.is_ok(),
            "Parse failed for {}: {:?}",
            path.display(),
            result.err()
        );
    }
}

/// Invoke tish binary to compile async-await and run compiled output (validates non-blocking pipeline).
#[test]
#[cfg(feature = "http")]
fn test_async_await_compile_via_binary() {
    let bin = tish_bin();
    let path = workspace_root()
        .join("examples")
        .join("async-await")
        .join("src")
        .join("main.tish");
    if path.exists() && bin.exists() {
        let out = std::env::temp_dir().join("tish_async_test_out");
        let compile_result = Command::new(&bin)
            .args([
                "build",
                path.to_string_lossy().as_ref(),
                "-o",
                out.to_string_lossy().as_ref(),
            ])
            .current_dir(workspace_root())
            .output();
        let compile_out = compile_result.expect("run tish build");
        assert!(
            compile_out.status.success(),
            "tish build failed: {}",
            String::from_utf8_lossy(&compile_out.stderr)
        );
        // Run compiled binary to validate non-blocking fetchAll executes correctly
        let run_result = Command::new(&out).current_dir(workspace_root()).output();
        let run_out = run_result.expect("run compiled async binary");
        assert!(
            run_out.status.success(),
            "compiled async binary failed: {}",
            String::from_utf8_lossy(&run_out.stderr)
        );
        let stdout = String::from_utf8_lossy(&run_out.stdout);
        assert!(
            stdout.contains("Fetching"),
            "expected output to mention fetching"
        );
        assert!(stdout.contains("Done"), "expected output to contain Done");
    }
}

/// DEFINITIVE VALIDATION: Parallel fetches must be faster than sequential.
/// Uses httpbin.org/delay/1 (1s each). 3 parallel ≈ 1s, 3 sequential ≈ 3s.
#[test]
#[cfg(feature = "http")]
#[ignore = "timing and network sensitive; run manually: cargo test test_async_parallel_vs_sequential_timing -p tishlang--features http -- --ignored"]
fn test_async_parallel_vs_sequential_timing() {
    let bin = tish_bin();
    let parallel_src = workspace_root()
        .join("examples")
        .join("async-await")
        .join("src")
        .join("parallel.tish");
    let sequential_src = workspace_root()
        .join("examples")
        .join("async-await")
        .join("src")
        .join("sequential.tish");
    if !parallel_src.exists() || !sequential_src.exists() || !bin.exists() {
        return;
    }
    let out_parallel = std::env::temp_dir().join("tish_parallel_timing");
    let out_sequential = std::env::temp_dir().join("tish_sequential_timing");

    // Compile both
    let compile_par = Command::new(&bin)
        .args([
            "build",
            parallel_src.to_string_lossy().as_ref(),
            "-o",
            out_parallel.to_string_lossy().as_ref(),
        ])
        .current_dir(workspace_root())
        .output();
    assert!(
        compile_par.as_ref().unwrap().status.success(),
        "compile parallel: {}",
        String::from_utf8_lossy(&compile_par.as_ref().unwrap().stderr)
    );

    let compile_seq = Command::new(&bin)
        .args([
            "build",
            sequential_src.to_string_lossy().as_ref(),
            "-o",
            out_sequential.to_string_lossy().as_ref(),
        ])
        .current_dir(workspace_root())
        .output();
    assert!(
        compile_seq.as_ref().unwrap().status.success(),
        "compile sequential: {}",
        String::from_utf8_lossy(&compile_seq.as_ref().unwrap().stderr)
    );

    // Run parallel and time
    let t_parallel = std::time::Instant::now();
    let run_par = Command::new(&out_parallel)
        .current_dir(workspace_root())
        .output();
    let elapsed_parallel = t_parallel.elapsed();
    assert!(
        run_par.as_ref().unwrap().status.success(),
        "run parallel: {}",
        String::from_utf8_lossy(&run_par.as_ref().unwrap().stderr)
    );

    // Run sequential and time
    let t_sequential = std::time::Instant::now();
    let run_seq = Command::new(&out_sequential)
        .current_dir(workspace_root())
        .output();
    let elapsed_sequential = t_sequential.elapsed();
    assert!(
        run_seq.as_ref().unwrap().status.success(),
        "run sequential: {}",
        String::from_utf8_lossy(&run_seq.as_ref().unwrap().stderr)
    );

    // PARALLEL MUST BE FASTER: parallel < sequential * 0.6 (parallel ~1s, sequential ~3s)
    let parallel_secs = elapsed_parallel.as_secs_f64();
    let sequential_secs = elapsed_sequential.as_secs_f64();
    assert!(
        parallel_secs < sequential_secs * 0.6,
        "Async NOT validated: parallel took {:.2}s but sequential took {:.2}s. Parallel must be < 60% of sequential to prove non-blocking.",
        parallel_secs,
        sequential_secs
    );
}

/// Run async-await example via tishlang_eval (same path as `tish run`).
/// Ignored: tishlang_eval::run() is synchronous and does not run the event loop.
#[test]
#[cfg(feature = "http")]
#[ignore = "requires async runtime; use test_async_await_compile_via_binary for CI"]
fn test_async_await_run() {
    let path = workspace_root()
        .join("examples")
        .join("async-await")
        .join("src")
        .join("main.tish");
    if path.exists() {
        let source = std::fs::read_to_string(&path).unwrap();
        let result = tishlang_eval::run(&source);
        assert!(
            result.is_ok(),
            "Run failed for {}: {:?}",
            path.display(),
            result.err()
        );
    }
}

/// `promise.tish` — full Promise API including `new Promise(executor)`, `.then`, `.catch`,
/// `all`, `race`, `any`, `allSettled`. Runs via the binary (vm + interp), asserts exact output.
/// This was previously `#[ignore]`'d and only checked "doesn't error" — the old fixture also
/// avoided `new Promise` entirely, hiding a bug where the executor never ran on the VM. Now
/// CI-gated and output-asserting. vm ≡ interp.
#[test]
fn test_promise_core() {
    let bin = tish_bin();
    if !bin.exists() {
        return;
    }
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("promise.tish");
    if !path.exists() {
        return;
    }
    let expected = "\
new Promise: new-ctor
Promise sync resolve: 42
Promise.resolve: 100
Promise.reject caught: true
.then chain: 4
.catch: handled: fail
Promise.all: 1 2 3
Promise.race: fast
Promise.any: any-win
Promise.allSettled: fulfilled rejected reason
Promise tests completed
";
    for backend_args in [vec!["run"], vec!["run", "--backend", "interp"]] {
        let mut args = backend_args.clone();
        args.push(path.to_string_lossy().to_string().leak());
        let out = Command::new(&bin)
            .args(&args)
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "promise.tish ({:?}) failed: stderr={}",
            backend_args,
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "Promise output mismatch on backend {:?} — check new Promise/any/allSettled regressions",
            backend_args
        );
    }
}

/// Import aliasing — `{ x as y }` rename and `* as M` namespace. `as` is a dedicated keyword
/// token (shared with type casts), so the import-specifier parser must accept it in that position.
/// Regression: previously `import { a as b }` failed with "Expected Comma, got As". vm ≡ interp.
#[test]
fn test_import_alias() {
    let bin = tish_bin();
    if !bin.exists() {
        return;
    }
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("import_alias.tish");
    if !path.exists() {
        return;
    }
    let expected = "42\nhi there\n42\n1.0\n";
    for backend_args in [vec!["run"], vec!["run", "--backend", "vm"]] {
        let mut args = backend_args.clone();
        args.push(path.to_string_lossy().to_string().leak());
        let out = Command::new(&bin)
            .args(&args)
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "import_alias.tish ({:?}) failed: stderr={}",
            backend_args,
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "import alias output mismatch on backend {:?}",
            backend_args
        );
    }
}

/// Combined validation: async/await + Promise + setTimeout + multiple HTTP requests.
/// #97: a module's non-exported top-level bindings stay private — a same-named binding in
/// another module must not overwrite them (runtime), and the `--target js` bundle must not
/// emit duplicate `let` declarations (SyntaxError). Verified identical across interp / VM /
/// native / node, including parameter and inner-`let` shadowing.
#[test]
fn test_module_private_binding_isolation() {
    let bin = tish_bin();
    if !bin.exists() {
        return;
    }
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("private_isolation.tish");
    if !path.exists() {
        return;
    }
    let expected = "from-a:helper-a from-b:helper-b\narg inner\nhelper-b\n";

    // Interpreter + VM via `tish run`.
    for backend in ["interp", "vm"] {
        let out = Command::new(&bin)
            .args(["run", "--backend", backend])
            .arg(&path)
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "private_isolation.tish ({backend}) failed: stderr={}",
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "module private-binding isolation mismatch on backend {backend}"
        );
    }

    // Native: compile + run.
    let native_bin = compile_cached(&bin, &path, "native");
    let out = Command::new(&native_bin)
        .current_dir(workspace_root())
        .output()
        .expect("run native binary");
    let _ = std::fs::remove_file(&native_bin);
    assert!(
        out.status.success(),
        "private_isolation native run failed: stderr={}",
        String::from_utf8_lossy(&out.stderr)
    );
    assert_eq!(
        String::from_utf8_lossy(&out.stdout),
        expected,
        "module private-binding isolation mismatch on native backend"
    );

    // JS target: compile + run through Node (also asserts no duplicate-`let` SyntaxError).
    let node_available = Command::new("node")
        .arg("--version")
        .output()
        .map(|o| o.status.success())
        .unwrap_or(false);
    if node_available {
        let out_js = compile_cached(&bin, &path, "js");
        let out = Command::new("node")
            .arg(&out_js)
            .current_dir(workspace_root())
            .output()
            .expect("run node");
        let _ = std::fs::remove_file(&out_js);
        assert!(
            out.status.success(),
            "private_isolation JS run failed: stderr={}",
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "module private-binding isolation mismatch on JS target"
        );
    }
}

/// Ignored: tishlang_eval::run() does not run the event loop.
#[test]
#[cfg(feature = "http")]
#[ignore = "requires async runtime"]
fn test_async_promise_settimeout_combined() {
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("async_promise_settimeout.tish");
    if path.exists() {
        let source = std::fs::read_to_string(&path).unwrap();
        let result = tishlang_eval::run(&source);
        assert!(
            result.is_ok(),
            "Failed to run async_promise_settimeout: {:?}",
            result.err()
        );
    }
}

/// VM run with Date global (resolve+merge+bytecode+run pipeline).
#[test]
fn test_vm_date_now() {
    let path = workspace_root()
        .join("tests")
        .join("core")
        .join("date.tish");
    if !path.exists() {
        return;
    }
    // Library path
    let modules = tishlang_compile::resolve_project(&path, path.parent()).expect("resolve");
    tishlang_compile::detect_cycles(&modules).expect("cycles");
    let program = tishlang_compile::merge_modules(modules)
        .expect("merge")
        .program;
    let chunk = tishlang_bytecode::compile(&program).expect("compile");
    let result = tishlang_vm::run(&chunk);
    assert!(
        result.is_ok(),
        "VM run (library) failed: {:?}",
        result.err()
    );
    // Binary path - same flow as `tish run <file>`
    let bin = tish_bin();
    if bin.exists() {
        let out = Command::new(&bin)
            .args(["run", path.to_string_lossy().as_ref()])
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "tish run failed: stdout={} stderr={}",
            String::from_utf8_lossy(&out.stdout),
            String::from_utf8_lossy(&out.stderr)
        );
    }
}

/// `Promise.any`, `Promise.allSettled`, fixed `Promise.race` — cross-backend, network-free, CI-gated.
/// vm ≡ interp exact match.
#[test]
fn test_promise_combinators() {
    let bin = tish_bin();
    if !bin.exists() {
        return;
    }
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("promise_combinators.tish");
    if !path.exists() {
        return;
    }
    let expected = "\
any first-fulfilled: win
any all-rejected: [\"e1\",\"e2\"]
allSettled[0] ok: 10
allSettled[1] rejected: boom
allSettled[2] ok: 30
race winner: A
any passthrough: 42
";
    for backend_args in [vec!["run"], vec!["run", "--backend", "interp"]] {
        let mut args = backend_args.clone();
        args.push(path.to_string_lossy().to_string().leak());
        let out = Command::new(&bin)
            .args(&args)
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "promise_combinators ({:?}) failed: stderr={}",
            backend_args,
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "Promise.any/allSettled/race divergence on backend {:?}",
            backend_args
        );
    }
}

/// Pins tish's DOCUMENTED async/Promise ordering (docs/concurrency-model.md) — network-free, so it
/// runs in CI (unlike the `#[ignore]`'d network async tests). Asserts Promise.all order + non-promise
/// passthrough, `.then` chaining, await-reject catch, Promise.all reject short-circuit, AND the
/// deliberate blocking signature: a 0ms `setTimeout` queued before an `await` fires LAST (a JS event
/// loop would interleave it earlier — tish's `await` blocks instead of yielding). NOT compared to node
/// on purpose; this is tish's own contract. vm ≡ interp guards cross-backend agreement.
#[test]
fn test_async_ordering_documented() {
    let bin = tish_bin();
    if !bin.exists() {
        return;
    }
    let path = workspace_root()
        .join("tests")
        .join("modules")
        .join("async_ordering.tish");
    if !path.exists() {
        return;
    }
    // tish's documented, deliberately-non-JS ordering (timer drains last because await blocks).
    let expected = "\
1: sync-start
2: await = 42
2b: new Promise = ctor-ran
3: all = a b c
4: chain = 13
5: caught = boom
6: all-reject = rej
7: post-await = after-timer-was-queued
9: sync-end
8: timer-fires-LAST (await did not yield)
";
    // Both the bytecode VM and the tree-walking interpreter must agree on this contract.
    for backend_args in [vec!["run"], vec!["run", "--backend", "interp"]] {
        let mut args = backend_args.clone();
        args.push(path.to_string_lossy().to_string().leak());
        let out = Command::new(&bin)
            .args(&args)
            .current_dir(workspace_root())
            .output()
            .expect("run tish binary");
        assert!(
            out.status.success(),
            "async_ordering ({:?}) failed: stderr={}",
            backend_args,
            String::from_utf8_lossy(&out.stderr)
        );
        assert_eq!(
            String::from_utf8_lossy(&out.stdout),
            expected,
            "async ordering divergence on backend {:?} — the documented blocking-await/timer contract changed",
            backend_args
        );
    }
}

/// VM run with parse+compile only (no resolve/merge) - isolates bytecode IndexAssign.
#[test]
fn test_vm_index_assign_direct() {
    let source = r#"let arr = [1, 2, 3]; arr[1] = 99; console.log(arr[1]);"#;
    let program = tishlang_parser::parse(source).expect("parse");
    let chunk = tishlang_bytecode::compile(&program).expect("compile");
    let result = tishlang_vm::run(&chunk);
    assert!(result.is_ok(), "VM IndexAssign failed: {:?}", result.err());
}

/// VM run via resolve+merge (same as tish run) - must also pass.
#[test]
fn test_vm_index_assign_via_resolve() {
    let path = workspace_root()
        .join("tests")
        .join("core")
        .join("array_sort_minimal.tish");
    let modules = tishlang_compile::resolve_project(&path, path.parent()).expect("resolve");
    tishlang_compile::detect_cycles(&modules).expect("cycles");
    let program = tishlang_compile::merge_modules(modules)
        .expect("merge")
        .program;
    let chunk = tishlang_bytecode::compile(&program).expect("compile");
    let result = tishlang_vm::run(&chunk);
    assert!(
        result.is_ok(),
        "VM IndexAssign via resolve failed: {:?}",
        result.err()
    );
}

/// tish run binary must pass array_sort_minimal (ensures CLI works).
#[test]
fn test_tish_run_index_assign() {
    let bin = tish_bin();
    let path = workspace_root()
        .join("tests")
        .join("core")
        .join("array_sort_minimal.tish");
    if !bin.exists() {
        eprintln!("Skipping: tish binary not built");
        return;
    }
    let out = Command::new(&bin)
        .args(["run", path.to_string_lossy().as_ref()])
        .current_dir(workspace_root())
        .output()
        .expect("run tish");
    assert!(
        out.status.success(),
        "tish run failed: stdout={} stderr={}",
        String::from_utf8_lossy(&out.stdout),
        String::from_utf8_lossy(&out.stderr)
    );
    assert!(
        String::from_utf8_lossy(&out.stdout).contains("pass"),
        "Expected 'pass' in output"
    );
}

/// Full stack: lex + parse each .tish file and assert no parse error.
#[test]
fn test_full_stack_parse() {
    let core_dir = core_dir();
    for entry in std::fs::read_dir(&core_dir).unwrap() {
        let path = entry.unwrap().path();
        if path.extension().map(|e| e == "tish").unwrap_or(false) {
            let source = std::fs::read_to_string(&path).unwrap();
            let result = tishlang_parser::parse(&source);
            assert!(
                result.is_ok(),
                "Parse failed for {}: {:?}",
                path.display(),
                result.err()
            );
        }
    }
}

// (The hand-maintained `MVP_TEST_FILES` allowlist was removed in favor of `discover_core_tests()`
// below — every `tests/core/*.tish` with a `.expected` now gets cross-backend coverage automatically.)

/// Tests whose `.expected` embeds elapsed-ms timings (perf/stress/probe) — nondeterministic, so
/// excluded from exact-output comparison. Run them via `just perf-*` instead.
const TIMING_NONDETERMINISTIC: &[&str] = &[
    "array_stress.tish",
    "array_stress_01_large_array_creation.tish",
    "array_stress_02_iteration.tish",
    "array_stress_03_map_filter_reduce.tish",
    "array_stress_04_chained.tish",
    "array_stress_05_sorting.tish",
    "array_stress_06_search.tish",
    "array_stress_07_splice_slice.tish",
    "array_stress_08_concat_spread.tish",
    "array_stress_09_flat.tish",
    "array_stress_10_objects.tish",
    "basic_types.tish",
    "benchmark_granular.tish",
    "new_features_perf.tish",
    "object_stress.tish",
    "objects_perf.tish",
    "string_methods_perf.tish",
    "recursion_stress.tish",
    "jit_probe.tish",
];

/// Known cross-backend gaps skipped on the interp↔vm parity check, with reason + a tracking note.
/// Each is a real divergence to fix, not a permanent exclusion.
///
/// Empty: the former `nested_complex.tish` gap (the VM's fixed 2-level `enclosing` lost captures
/// >2 levels deep — `level4` couldn't see `level1`'s `a`) is fixed. The VM now captures the full
/// lexical chain (`Vm.enclosing: Vec<ScopeMap>`), so closures nested arbitrarily deep resolve
/// every ancestor's locals. interp↔vm parity holds for all discovered tests.
const VM_PARITY_SKIP: &[&str] = &[];

/// Discover every `tests/core/*.tish` that has a `.expected` sibling, minus timing-nondeterministic
/// ones. Replaces the hand-maintained `MVP_TEST_FILES` allowlist so a new `*.tish` + `*.expected`
/// gets cross-backend coverage automatically (the allowlist silently left ~38 tests running nowhere).
fn discover_core_tests() -> Vec<String> {
    let mut v: Vec<String> = std::fs::read_dir(core_dir())
        .expect("read tests/core")
        .filter_map(|e| {
            let p = e.ok()?.path();
            if p.extension().map(|x| x == "tish").unwrap_or(false) && expected_path(&p).exists() {
                Some(p.file_name()?.to_string_lossy().into_owned())
            } else {
                None
            }
        })
        .filter(|n| !TIMING_NONDETERMINISTIC.contains(&n.as_str()))
        .collect();
    v.sort();
    v
}

/// True if `name` has a sibling `.js` (so it can run through the Node oracle).
fn has_js_sibling(name: &str) -> bool {
    core_dir()
        .join(name)
        .with_extension("js")
        .exists()
}

/// The gradual type checker must produce ZERO diagnostics on the (valid) corpus — any diagnostic is
/// a false positive. Lists every offender so they can be inspected/fixed.
#[test]
fn checker_no_false_positives_on_corpus() {
    let mut flagged: Vec<String> = Vec::new();
    for name in discover_core_tests() {
        let src = std::fs::read_to_string(core_dir().join(&name)).unwrap();
        if let Ok(prog) = tishlang_parser::parse(&src) {
            let diags = tishlang_compile::check_program(&prog);
            if !diags.is_empty() {
                let msgs: Vec<String> = diags.iter().map(|d| d.message.clone()).collect();
                flagged.push(format!("{name}: {}", msgs.join(" | ")));
            }
        }
    }
    assert!(
        flagged.is_empty(),
        "type checker flagged valid corpus programs (false positives):\n{}",
        flagged.join("\n")
    );
}

/// Run each .tish file with interpreter and compare stdout to static expected.
/// Set REGENERATE_EXPECTED=1 to write .expected files from interpreter output (run once, then commit).
#[test]
fn test_mvp_programs_interpreter() {
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );
    let regenerate = std::env::var("REGENERATE_EXPECTED").as_deref() == Ok("1");
    for name in &discover_core_tests() {
        let path = core_dir.join(name);
        if !path.exists() {
            continue;
        }
        let path_str = path.to_string_lossy();
        let out = Command::new(&bin)
            .args(["run", path_str.as_ref(), "--backend", "interp"])
            .current_dir(workspace_root())
            .output()
            .expect("run tish interpreter");
        assert!(
            out.status.success(),
            "Interpreter failed for {}: {}",
            path.display(),
            String::from_utf8_lossy(&out.stderr)
        );
        let stdout = String::from_utf8_lossy(&out.stdout).to_string();
        if regenerate {
            std::fs::write(expected_path(&path), &stdout).expect("write expected");
        } else {
            let expected = get_expected(&path).unwrap_or_else(|| {
                panic!(
                    "missing expected file for {}; run with REGENERATE_EXPECTED=1 to generate",
                    path.display()
                )
            });
            assert_eq!(
                stdout,
                expected,
                "Interpreter output mismatch for {}",
                path.display()
            );
        }
    }
}

/// Default bytecode VM must match the tree-walking interpreter for every MVP program.
#[test]
fn test_mvp_programs_interp_vm_stdout_parity() {
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );
    for name in &discover_core_tests() {
        if VM_PARITY_SKIP.contains(&name.as_str()) {
            continue;
        }
        let path = core_dir.join(name);
        if !path.exists() {
            continue;
        }
        let path_str = path.to_string_lossy();
        let out_interp = Command::new(&bin)
            .args(["run", path_str.as_ref(), "--backend", "interp"])
            .current_dir(workspace_root())
            .output()
            .expect("run tish interpreter");
        assert!(
            out_interp.status.success(),
            "Interpreter failed for {}: {}",
            path.display(),
            String::from_utf8_lossy(&out_interp.stderr)
        );
        let out_vm = Command::new(&bin)
            .args(["run", path_str.as_ref()])
            .current_dir(workspace_root())
            .output()
            .expect("run tish VM");
        assert!(
            out_vm.status.success(),
            "VM failed for {}: {}",
            path.display(),
            String::from_utf8_lossy(&out_vm.stderr)
        );
        let s_interp = String::from_utf8_lossy(&out_interp.stdout);
        let s_vm = String::from_utf8_lossy(&out_vm.stdout);
        assert_eq!(
            s_interp,
            s_vm,
            "interp vs VM stdout mismatch for {}",
            path.display()
        );
    }
}

/// Compile each .tish file to native, run, and compare stdout to static expected (parallelized).
#[test]
fn test_mvp_programs_native() {
    let _fast_native = EnvVarGuard::set("TISH_FAST_NATIVE_BUILD", "1");
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );

    let mut paths: Vec<PathBuf> = discover_core_tests()
        .iter()
        .filter_map(|name| {
            let p = core_dir.join(name);
            if p.exists() {
                Some(p)
            } else {
                None
            }
        })
        .collect();
    paths.sort();

    if paths.is_empty() {
        return;
    }

    let combined = combined_mvp_native_inputs_hash(&paths);
    let cache_dir = mvp_native_batch_cache_dir(combined);
    let _ = std::fs::create_dir_all(&cache_dir);

    let ext = if cfg!(target_os = "windows") {
        ".exe"
    } else {
        ""
    };

    let entries_owned: Vec<(PathBuf, PathBuf)> = paths
        .iter()
        .map(|p| {
            let stem = p.file_stem().unwrap().to_string_lossy();
            let cached = cache_dir.join(format!("{}{}", stem, ext));
            (p.clone(), cached)
        })
        .collect();

    let need_build = entries_owned.iter().any(|(_, o)| !o.exists());
    if need_build {
        let refs: Vec<(&Path, &Path)> = entries_owned
            .iter()
            .map(|(a, b)| (a.as_path(), b.as_path()))
            .collect();
        let feats = native_build_features_for_integration_test();
        compile_many_to_native(&refs, Some(workspace_root().as_path()), &feats, true)
            .unwrap_or_else(|e| panic!("compile_many_to_native: {}", e.message));
    }

    // Run each binary sequentially. Parallel `fs::copy` + `exec` caused Linux ETXTBSY (errno 26)
    // in CI when several threads replaced/ran temp executables under load.
    let errors: Vec<String> = entries_owned
        .iter()
        .enumerate()
        .filter_map(|(run_index, (path, cached_bin))| {
            let expected = match get_expected(path) {
                Some(e) => e,
                None => return Some(format!("missing expected: {}", path.display())),
            };
            if !cached_bin.exists() {
                return Some(format!("missing cached binary: {}", cached_bin.display()));
            }
            let stem = path.file_stem().unwrap().to_string_lossy();
            let ext_bin = cached_bin
                .extension()
                .map(|e| e.to_string_lossy().to_string())
                .unwrap_or_default();
            let temp_dest = std::env::temp_dir().join(format!(
                "tish_mvp_native_{}_{:x}_{}_{}",
                stem,
                file_content_hash(path),
                std::process::id(),
                run_index
            ));
            let temp_dest = if ext_bin.is_empty() {
                temp_dest
            } else {
                temp_dest.with_extension(&ext_bin)
            };
            std::fs::copy(cached_bin, &temp_dest).expect("copy cached native bin to temp");
            let out_bin = temp_dest;
            let out = match Command::new(&out_bin)
                .current_dir(workspace_root())
                .output()
            {
                Ok(o) => o,
                Err(e) => {
                    let _ = std::fs::remove_file(&out_bin);
                    return Some(format!("{}: run failed: {}", path.display(), e));
                }
            };
            let _ = std::fs::remove_file(&out_bin);
            if !out.status.success() {
                return Some(format!(
                    "{}: {}",
                    path.display(),
                    String::from_utf8_lossy(&out.stderr)
                ));
            }
            let stdout = String::from_utf8_lossy(&out.stdout);
            if stdout != expected {
                return Some(format!("{}: output mismatch", path.display()));
            }
            None
        })
        .collect();
    assert!(errors.is_empty(), "native failures:\n{}", errors.join("\n"));
}

// cranelift + wasi now use `discover_core_tests()` (full file discovery), like interp/vm/native —
// the former curated `CRANELIFT_TEST_FILES` allowlist is gone. They embed the bytecode VM, which
// has full interp↔vm parity (`VM_PARITY_SKIP` empty), so they inherit it: a disk-safe sweep confirmed
// cranelift 66/66 and wasi 66/66. The old blocker was build COST — each backend build used to emit a
// per-program `target/` (~2-5 GB) that accumulated to ~130 GB; now `tish_cranelift`/`tish_wasm` build
// into a SHARED target dir so the deps compile once (610 MB / 85 MB total for the whole sweep, and a
// repeat build is ~1 s). If a construct ever regresses on a backend, add it to a documented skip set
// rather than re-introducing an allowlist.

/// Compile each .tish file with Cranelift backend, run, and compare stdout to static expected (parallelized).
#[test]
fn test_mvp_programs_cranelift() {
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );
    let errors: Vec<String> = discover_core_tests()
        .par_iter()
        .filter_map(|name| {
            let path = core_dir.join(name);
            if !path.exists() {
                return None;
            }
            let expected = match get_expected(&path) {
                Some(e) => e,
                None => return Some(format!("missing expected: {}", path.display())),
            };
            let out_bin = compile_cached(&bin, &path, "cranelift");
            let out = match Command::new(&out_bin)
                .current_dir(workspace_root())
                .output()
            {
                Ok(o) => o,
                Err(e) => {
                    let _ = std::fs::remove_file(&out_bin);
                    return Some(format!("{}: run failed: {}", path.display(), e));
                }
            };
            let _ = std::fs::remove_file(&out_bin);
            if !out.status.success() {
                return Some(format!(
                    "{}: {}",
                    path.display(),
                    String::from_utf8_lossy(&out.stderr)
                ));
            }
            let stdout = String::from_utf8_lossy(&out.stdout);
            if stdout != expected {
                return Some(format!("{}: output mismatch", path.display()));
            }
            None
        })
        .collect();
    assert!(
        errors.is_empty(),
        "cranelift failures:\n{}",
        errors.join("\n")
    );
}

/// Compile each .tish file to WASI, run with wasmtime, and compare stdout to static expected (parallelized).
/// Skips if wasmtime is not available.
#[test]
fn test_mvp_programs_wasi() {
    let wasmtime_available = Command::new("wasmtime")
        .arg("--version")
        .output()
        .map(|o| o.status.success())
        .unwrap_or(false);
    if !wasmtime_available {
        eprintln!("Skipping test_mvp_programs_wasi: wasmtime not found");
        return;
    }
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );
    let errors: Vec<String> = discover_core_tests()
        .par_iter()
        .filter_map(|name| {
            let path = core_dir.join(name);
            if !path.exists() {
                return None;
            }
            let expected = match get_expected(&path) {
                Some(e) => e,
                None => return Some(format!("missing expected: {}", path.display())),
            };
            let out_wasm = compile_cached(&bin, &path, "wasi");
            let out = match Command::new("wasmtime")
                .arg(out_wasm.as_os_str())
                .current_dir(workspace_root())
                .output()
            {
                Ok(o) => o,
                Err(e) => {
                    let _ = std::fs::remove_file(&out_wasm);
                    return Some(format!("{}: wasmtime failed: {}", path.display(), e));
                }
            };
            let _ = std::fs::remove_file(&out_wasm);
            if !out.status.success() {
                return Some(format!(
                    "{}: {}",
                    path.display(),
                    String::from_utf8_lossy(&out.stderr)
                ));
            }
            let stdout = String::from_utf8_lossy(&out.stdout);
            if stdout != expected {
                return Some(format!("{}: output mismatch", path.display()));
            }
            None
        })
        .collect();
    assert!(errors.is_empty(), "wasi failures:\n{}", errors.join("\n"));
}

/// Files where Tish intentionally differs from JavaScript (typeof, void); skip in JS test since we compare to Tish expected.
const JS_SKIP_FILES: &[&str] = &["typeof.tish", "void.tish"];

/// Compile each .tish file to JS, run with Node, and compare stdout to static expected.
#[test]
fn test_mvp_programs_js() {
    let node_available = Command::new("node")
        .args(["--version"])
        .output()
        .map(|o| o.status.success())
        .unwrap_or(false);
    if !node_available {
        eprintln!("Skipping test_mvp_programs_js: Node.js not found");
        return;
    }
    let core_dir = core_dir();
    let bin = tish_bin();
    assert!(
        bin.exists(),
        "tish binary not found at {}. Run `cargo build -p tishlang` first.",
        bin.display()
    );
    for name in &discover_core_tests() {
        // intentional JS divergences + tests without a `.js` sibling can't use the Node oracle
        if JS_SKIP_FILES.contains(&name.as_str()) || !has_js_sibling(name) {
            continue;
        }
        let path = core_dir.join(name);
        if !path.exists() {
            continue;
        }
        let expected = get_expected(&path).unwrap_or_else(|| {
            panic!(
                "missing expected file for {}; run with REGENERATE_EXPECTED=1 to generate",
                path.display()
            )
        });
        let out_js = compile_cached(&bin, &path, "js");
        let out = Command::new("node")
            .arg(&out_js)
            .current_dir(workspace_root())
            .output()
            .expect("run node");
        let _ = std::fs::remove_file(&out_js);
        assert!(
            out.status.success(),
            "Node failed for {}: {}",
            path.display(),
            String::from_utf8_lossy(&out.stderr)
        );
        let stdout = String::from_utf8_lossy(&out.stdout);
        assert_eq!(
            stdout,
            expected,
            "JS output mismatch for {}",
            path.display()
        );
    }
}