cljrs_runtime/interp/

eval.rs

//! Top-level `eval` dispatcher and form-to-value conversion.

use std::sync::Arc;

use crate::builtins::form::{expand_pairs, expand_reader_conds, expand_reader_conds_cow};
use crate::builtins::special::SPECIAL_FORMS;
use crate::env::env::Env;
use crate::env::error::{EvalError, EvalResult};
use crate::interp::apply::eval_call;
use crate::interp::special::eval_special;
use crate::interp::syntax_quote::syntax_quote;
use cljrs_gc::GcPtr;
use cljrs_reader::Form;
use cljrs_reader::form::FormKind;
use cljrs_value::value::SetValue;
use cljrs_value::{
    FutureState, Keyword, MapValue, PersistentHashSet, PersistentList, PersistentVector, Symbol,
    Value,
};
use regex::Regex;

/// Evaluate a `Form` in the given `Env`.
pub fn eval(form: &Form, env: &mut Env) -> EvalResult {
    if !crate::env::gas::charge(1) {
        return Err(EvalError::GasExhausted);
    }
    match &form.kind {
        // ── Atoms ─────────────────────────────────────────────────────────
        FormKind::Nil => Ok(Value::Nil),
        FormKind::Bool(b) => Ok(Value::Bool(*b)),
        FormKind::Int(n) => Ok(Value::Long(*n)),
        FormKind::Float(f) => Ok(Value::Double(*f)),
        FormKind::Symbolic(f) => Ok(Value::Double(*f)), // ##Inf etc.
        FormKind::Str(s) => Ok(Value::string(s.clone())),
        FormKind::Char(c) => Ok(Value::Char(*c)),
        FormKind::BigInt(s) => crate::builtins::parse_bigint(s),
        FormKind::BigDecimal(s) => crate::builtins::parse_bigdecimal(s),
        FormKind::Ratio(s) => crate::builtins::parse_ratio(s),
        FormKind::Regex(s) => {
            let r = Regex::new(s);
            match r {
                Ok(r) => Ok(Value::Pattern(GcPtr::new(r))),
                Err(e) => Err(EvalError::Runtime(e.to_string())),
            }
        }

        // ── Identifiers ───────────────────────────────────────────────────
        FormKind::Symbol(s) => eval_symbol(s, env),
        FormKind::Keyword(s) => Ok(Value::keyword(Keyword::parse(s))),
        FormKind::AutoKeyword(s) => {
            let full = env
                .globals
                .resolve_auto_keyword(&env.current_ns, s)
                .map_err(EvalError::Runtime)?;
            Ok(Value::keyword(Keyword::parse(&full)))
        }
        // A symbol key from an auto-resolved namespaced map: in evaluated
        // position it names a var, exactly as a written-out symbol key does.
        FormKind::AutoSymbol(s) => {
            let full = env
                .globals
                .resolve_auto_keyword(&env.current_ns, s)
                .map_err(EvalError::Runtime)?;
            eval_symbol(&full, env)
        }

        // ── Collections ───────────────────────────────────────────────────
        FormKind::List(forms) => eval_list(forms, env),
        FormKind::Vector(forms) => {
            let forms = expand_reader_conds_cow(forms);
            let mut vals: Vec<Value> = Vec::with_capacity(forms.len());
            for f in forms.iter() {
                let _root = crate::env::gc_roots::root_values(&vals);
                vals.push(eval(f, env)?);
            }
            Ok(Value::Vector(GcPtr::new(PersistentVector::from_iter(vals))))
        }
        FormKind::Map(forms) => {
            let forms = expand_pairs(forms).map_err(|_| {
                EvalError::Runtime("map literal must have an even number of forms".into())
            })?;
            let mut pairs: Vec<Value> = Vec::with_capacity(forms.len());
            for f in forms.iter() {
                let _root = crate::env::gc_roots::root_values(&pairs);
                pairs.push(eval(f, env)?);
            }
            let kv_pairs: Vec<(Value, Value)> = pairs
                .chunks(2)
                .map(|pair| (pair[0].clone(), pair[1].clone()))
                .collect();
            Ok(Value::Map(MapValue::from_pairs(kv_pairs)))
        }
        FormKind::Set(forms) => {
            let forms = expand_reader_conds_cow(forms);
            let mut vals: Vec<Value> = Vec::with_capacity(forms.len());
            for f in forms.iter() {
                let _root = crate::env::gc_roots::root_values(&vals);
                vals.push(eval(f, env)?);
            }
            Ok(Value::Set(SetValue::Hash(GcPtr::new(
                PersistentHashSet::from_iter(vals),
            ))))
        }

        // ── Reader macros ─────────────────────────────────────────────────
        // `'x` sugar: like the `quote` special form, `::kw` and an
        // auto-resolved map's symbol keys resolve against the reading
        // namespace before the form becomes data.
        FormKind::Quote(inner) => {
            let resolved = crate::builtins::form::resolve_auto_forms(inner, env)?;
            crate::builtins::form::form_to_value(&resolved)
        }
        FormKind::SyntaxQuote(inner) => syntax_quote(inner, env),
        FormKind::Unquote(_) => Err(EvalError::Runtime("unquote outside syntax-quote".into())),
        FormKind::UnquoteSplice(_) => Err(EvalError::Runtime(
            "unquote-splice outside syntax-quote".into(),
        )),
        FormKind::Deref(inner) => {
            let v = eval(inner, env)?;
            if env.is_async && matches!(v, Value::Future(_)) {
                return Err(EvalError::Runtime(
                    "deref (@) on a future is not allowed inside an ^:async function; use (await ...) instead".into(),
                ));
            }
            deref_value(v)
        }
        FormKind::Var(inner) => {
            if let FormKind::Symbol(s) = &inner.kind {
                let parsed = Symbol::parse(s);
                let ns: Arc<str> = match parsed.namespace.as_deref() {
                    Some(ns_part) => env
                        .globals
                        .resolve_alias(&env.current_ns, ns_part)
                        .unwrap_or_else(|| Arc::from(ns_part)),
                    None => env.current_ns.clone(),
                };
                env.globals
                    .lookup_var_in_ns(&ns, &parsed.name)
                    .map(Value::Var)
                    .ok_or_else(|| EvalError::UnboundSymbol(s.clone()))
            } else {
                Err(EvalError::Runtime("var requires a symbol".into()))
            }
        }
        FormKind::Meta(_, form) => {
            // Ignore metadata in Phase 4; just eval the annotated form.
            eval(form, env)
        }

        // ── Dispatch ──────────────────────────────────────────────────────
        FormKind::AnonFn(body) => {
            let expanded = crate::builtins::form::expand_anon_fn(body, form.span.clone());
            eval(&expanded, env)
        }
        FormKind::ReaderCond {
            splicing: _,
            clauses,
        } => eval_reader_cond(clauses, env),
        FormKind::TaggedLiteral(tag, inner) => eval_tagged_literal(tag, inner, env),
    }
}

/// Evaluate a form with a cooperative execution-credit budget.
///
/// Nested tree-walker, IR-interpreter, and JIT work shares this budget.  The
/// existing [`eval`] entry point remains unmetered unless called inside this
/// dynamic scope.
pub fn eval_with_gas(form: &Form, env: &mut Env, credits: u64) -> EvalResult {
    let meter = crate::env::gas::GasMeter::new(credits);
    let _guard = crate::env::gas::GasGuard::install(meter);
    eval(form, env)
}

// ── List / call dispatch ──────────────────────────────────────────────────────

fn eval_list(forms: &[Form], env: &mut Env) -> EvalResult {
    if forms.is_empty() {
        return Ok(Value::List(GcPtr::new(PersistentList::empty())));
    }

    // Expand reader conditionals (both splicing and non-splicing) before dispatch.
    let expanded: Vec<Form>;
    let forms: &[Form] = if forms
        .iter()
        .any(|f| matches!(f.kind, FormKind::ReaderCond { .. }))
    {
        expanded = expand_reader_conds(forms);
        if expanded.is_empty() {
            return Ok(Value::List(GcPtr::new(PersistentList::empty())));
        }
        &expanded
    } else {
        forms
    };

    // Check for special form.
    if let FormKind::Symbol(s) = &forms[0].kind
        && is_special_form(s)
    {
        return eval_special(s, &forms[1..], env);
    }

    eval_call(&forms[0], &forms[1..], env)
}

// ── Symbol resolution ─────────────────────────────────────────────────────────

fn eval_symbol(s: &str, env: &mut Env) -> EvalResult {
    let sym = Symbol::parse(s);

    // Explicit version suffix (`name@hash` or `ns/name@hash`): always a
    // namespace-level lookup — no local-frame fallback.
    #[cfg(not(target_arch = "wasm32"))]
    if let Some(ref commit) = sym.version.clone() {
        crate::env::policy::check_versioned_lookup()?;
        return crate::interp::versioned::resolve_versioned_symbol(&sym, commit, env);
    }
    #[cfg(target_arch = "wasm32")]
    if sym.version.is_some() {
        return Err(crate::env::error::EvalError::Runtime(
            "versioned symbols are not supported in WASM".to_string(),
        ));
    }

    // Local frames (params, let-bindings, closed-over vars) take priority for
    // unversioned symbols.
    if let Some(v) = env.lookup_local_frames(s) {
        return Ok(v);
    }

    // Inherited versioned context: if we are evaluating inside a versioned
    // function body, unversioned same-namespace symbols resolve at the inherited
    // commit rather than HEAD.  "Same namespace" includes a qualified
    // self-reference written with the base name (`mylib/x` inside `mylib@hash`).
    #[cfg(not(target_arch = "wasm32"))]
    if let Some(commit) = env.versioned_eval_commit.clone() {
        let is_same_ns = sym.namespace.is_none()
            || sym.namespace.as_deref() == Some(env.current_ns.as_ref())
            || sym.namespace.as_deref()
                == Some(crate::env::versioned::base_ns_name(&env.current_ns));
        if is_same_ns {
            return crate::interp::versioned::resolve_versioned_symbol(&sym, &commit, env);
        }
    }

    // Fall through to normal global namespace lookup.
    if let Some(v) = env.globals.lookup_in_ns(&env.current_ns, s) {
        return Ok(v);
    }

    // Namespace-qualified external symbol: `ns/name`
    if s.contains('/')
        && !s.starts_with('/')
        && let Some(ns_part) = &sym.namespace
    {
        let resolved: Arc<str> = env
            .globals
            .resolve_alias(&env.current_ns, ns_part)
            .unwrap_or_else(|| Arc::from(ns_part.as_ref()));
        // Qualified self-reference inside a versioned namespace: `mylib/x`
        // written in `mylib@hash`'s own source resolves at the pinned commit,
        // i.e. inside the versioned namespace itself.
        #[cfg(not(target_arch = "wasm32"))]
        let resolved: Arc<str> = if env.current_ns.as_ref() != resolved.as_ref()
            && crate::env::versioned::base_ns_name(&env.current_ns) == resolved.as_ref()
        {
            env.current_ns.clone()
        } else {
            resolved
        };
        return env
            .globals
            .lookup_in_ns(&resolved, &sym.name)
            .ok_or_else(|| EvalError::UnboundSymbol(s.to_string()));
    }

    // JVM class names resolve to themselves as symbols (for instance?, catch, etc.)
    if is_jvm_class_name(s) {
        return Ok(Value::symbol(Symbol::simple(s)));
    }

    Err(EvalError::UnboundSymbol(s.to_string()))
}

/// Recognise JVM-style class names used in Clojure for `instance?`, `catch`, etc.
pub fn is_jvm_class_name(s: &str) -> bool {
    matches!(
        s,
        "clojure.lang.BigInt"
            | "java.math.BigDecimal"
            | "java.math.BigInteger"
            | "clojure.lang.Ratio"
            | "java.lang.Long"
            | "java.lang.Double"
            | "java.lang.String"
            | "java.lang.Boolean"
            | "java.lang.Character"
            | "java.lang.Number"
            | "clojure.lang.Symbol"
            | "clojure.lang.Keyword"
            | "clojure.lang.PersistentList"
            | "clojure.lang.PersistentVector"
            | "clojure.lang.PersistentHashMap"
            | "clojure.lang.PersistentHashSet"
            | "clojure.lang.PersistentArrayMap"
            | "clojure.lang.IFn"
            | "clojure.lang.ISeq"
            | "clojure.lang.IPending"
            | "clojure.lang.Atom"
            | "clojure.lang.Var"
            | "clojure.lang.Namespace"
            | "java.util.UUID"
            | "java.lang.Exception"
            | "java.lang.Throwable"
            | "java.lang.Error"
            | "Exception"
            | "Throwable"
            | "Error"
            | "clojure.lang.ExceptionInfo"
            | "clojure.lang.IEditableCollection"
            | "Boolean"
            | "clojure.lang.PersistentQueue"
            | "java.util.regex.Pattern"
    )
}

// ── is_special_form ───────────────────────────────────────────────────────────

pub fn is_special_form(s: &str) -> bool {
    SPECIAL_FORMS.contains(&s)
}

// ── eval_body ─────────────────────────────────────────────────────────────────

/// Dereference a value: used by `@x` reader macro and the `deref` builtin.
pub fn deref_value(v: Value) -> EvalResult {
    match v {
        Value::Atom(a) => Ok(a.get().deref()),
        Value::SharedAtom(sa) => Ok(cljrs_value::demote(&sa.deref_val())),
        Value::Var(var) => crate::env::dynamics::deref_var(&var)
            .ok_or_else(|| EvalError::Runtime("unbound var".into())),
        Value::Volatile(vol) => Ok(vol.get().deref()),
        Value::Delay(d) => d.get().force().map_err(EvalError::Runtime),
        Value::Agent(a) => Ok(a.get().get_state()),
        Value::Reduced(inner) => Ok(*inner),
        Value::Promise(p) => Ok(p.get().deref_blocking()),
        Value::Future(f) => {
            let mut guard = f.get().state.lock().unwrap();
            loop {
                match &*guard {
                    FutureState::Done(v) => {
                        f.get().mark_observed();
                        return Ok(v.clone());
                    }
                    FutureState::Failed(v) => {
                        f.get().mark_observed();
                        return Err(EvalError::Thrown(v.clone()));
                    }
                    FutureState::GasExhausted => {
                        f.get().mark_observed();
                        return Err(EvalError::GasExhausted);
                    }
                    FutureState::Cancelled => {
                        return Err(EvalError::Runtime("future was cancelled".into()));
                    }
                    FutureState::Running => {
                        guard = f.get().cond.wait(guard).unwrap();
                    }
                }
            }
        }
        other => Err(EvalError::Runtime(format!(
            "cannot deref {}",
            other.type_name()
        ))),
    }
}

/// Evaluate a sequence of forms and return the value of the last one.
pub fn eval_body(forms: &[Form], env: &mut Env) -> EvalResult {
    let mut result = Value::Nil;
    for form in forms {
        result = eval(form, env)?;
    }
    Ok(result)
}

// ── reader cond ───────────────────────────────────────────────────────────────

fn eval_reader_cond(clauses: &[Form], env: &mut Env) -> EvalResult {
    // clauses = [kw form kw form ...]
    let mut i = 0;
    let mut default: Option<&Form> = None;
    while i + 1 < clauses.len() {
        match &clauses[i].kind {
            FormKind::Keyword(k) if k == "rust" => {
                return eval(&clauses[i + 1], env);
            }
            FormKind::Keyword(k) if k == "default" => {
                default = Some(&clauses[i + 1]);
            }
            _ => {}
        }
        i += 2;
    }
    match default {
        Some(f) => eval(f, env),
        None => Ok(Value::Nil),
    }
}

// ── tagged literals ──────────────────────────────────────────────────────────

fn eval_tagged_literal(tag: &str, inner: &Form, env: &mut Env) -> EvalResult {
    match tag {
        "uuid" => {
            let val = eval(inner, env)?;
            match &val {
                Value::Str(s) => {
                    let uuid = uuid::Uuid::parse_str(s.get())
                        .map_err(|e| EvalError::Runtime(format!("invalid UUID: {e}")))?;
                    Ok(Value::Uuid(uuid.as_u128()))
                }
                _ => Err(EvalError::Runtime(format!(
                    "#uuid expects a string, got {}",
                    val.type_name()
                ))),
            }
        }
        "inst" => {
            // TODO: implement #inst for date/time literals
            let val = eval(inner, env)?;
            Ok(val)
        }
        _ => Err(EvalError::Runtime(format!(
            "unknown tagged literal: #{tag}"
        ))),
    }
}

// ── Tests ─────────────────────────────────────────────────────────────────────

#[cfg(test)]
mod tests {
    use super::*;
    use crate::env::env::GlobalEnv;
    use std::sync::Arc;

    fn make_env() -> (Arc<GlobalEnv>, Env) {
        let globals = crate::interp::standard_env(None, None, None);
        let env = Env::new(globals.clone(), "user");
        (globals, env)
    }

    fn eval_str(src: &str) -> EvalResult {
        let (_, mut env) = make_env();
        eval_src(src, &mut env)
    }

    fn eval_src(src: &str, env: &mut Env) -> EvalResult {
        let mut parser = cljrs_reader::Parser::new(src.to_string(), "<test>".to_string());
        let forms = parser.parse_all().map_err(EvalError::Read)?;
        let mut result = Value::Nil;
        for form in forms {
            result = eval(&form, env)?;
        }
        Ok(result)
    }

    fn long(n: i64) -> Value {
        Value::Long(n)
    }
    fn bool_v(b: bool) -> Value {
        Value::Bool(b)
    }

    // ── Atoms ─────────────────────────────────────────────────────────────

    #[test]
    fn test_literal_int() {
        assert_eq!(eval_str("42").unwrap(), long(42));
    }

    #[test]
    fn test_literal_string() {
        assert!(matches!(eval_str("\"hello\"").unwrap(), Value::Str(_)));
    }

    #[test]
    fn test_literal_nil() {
        assert_eq!(eval_str("nil").unwrap(), Value::Nil);
    }

    #[test]
    fn test_literal_true() {
        assert_eq!(eval_str("true").unwrap(), bool_v(true));
    }

    #[test]
    fn test_literal_false() {
        assert_eq!(eval_str("false").unwrap(), bool_v(false));
    }

    // ── Arithmetic ────────────────────────────────────────────────────────

    #[test]
    fn test_add() {
        assert_eq!(eval_str("(+ 1 2)").unwrap(), long(3));
    }

    #[test]
    fn test_mul() {
        assert_eq!(eval_str("(* 2 3)").unwrap(), long(6));
    }

    #[test]
    fn test_div_exact() {
        assert_eq!(eval_str("(/ 10 2)").unwrap(), long(5));
    }

    #[test]
    fn test_sub() {
        assert_eq!(eval_str("(- 10 3)").unwrap(), long(7));
    }

    // ── let ───────────────────────────────────────────────────────────────

    #[test]
    fn test_let_simple() {
        assert_eq!(eval_str("(let* [x 1 y 2] (+ x y))").unwrap(), long(3));
    }

    #[test]
    fn test_let_shadowing() {
        assert_eq!(eval_str("(let* [x 1] (let* [x 10] x))").unwrap(), long(10));
    }

    // ── fn + call ─────────────────────────────────────────────────────────

    #[test]
    fn test_fn_call() {
        assert_eq!(eval_str("((fn* [x] (* x x)) 5)").unwrap(), long(25));
    }

    #[test]
    fn test_closure_capture() {
        assert_eq!(
            eval_str("(let* [n 3] ((fn* [x] (+ x n)) 4))").unwrap(),
            long(7)
        );
    }

    #[test]
    fn test_multi_arity_fn() {
        assert_eq!(
            eval_str("((fn* ([x] x) ([x y] (+ x y))) 1 2)").unwrap(),
            long(3)
        );
    }

    // ── recur / loop ──────────────────────────────────────────────────────

    #[test]
    fn test_loop_recur() {
        let result =
            eval_str("(loop* [i 0 acc 0] (if (= i 5) acc (recur (inc i) (+ acc i))))").unwrap();
        assert_eq!(result, long(10));
    }

    // ── def / defn ────────────────────────────────────────────────────────

    #[test]
    fn test_def() {
        let (_, mut env) = make_env();
        eval_src("(def x 42)", &mut env).unwrap();
        assert_eq!(eval_src("x", &mut env).unwrap(), long(42));
    }

    #[test]
    fn test_defn() {
        let (_, mut env) = make_env();
        eval_src("(defn square [x] (* x x))", &mut env).unwrap();
        assert_eq!(eval_src("(square 7)", &mut env).unwrap(), long(49));
    }

    // ── if ────────────────────────────────────────────────────────────────

    #[test]
    fn test_if_truthy() {
        assert_eq!(eval_str("(if true 1 2)").unwrap(), long(1));
    }

    #[test]
    fn test_if_falsy() {
        assert_eq!(eval_str("(if false 1 2)").unwrap(), long(2));
    }

    #[test]
    fn test_if_nil_branch() {
        assert_eq!(eval_str("(if false 1)").unwrap(), Value::Nil);
    }

    // ── do ────────────────────────────────────────────────────────────────

    #[test]
    fn test_do() {
        assert_eq!(eval_str("(do 1 2 3)").unwrap(), long(3));
    }

    // ── quote ─────────────────────────────────────────────────────────────

    #[test]
    fn test_quote_list() {
        let v = eval_str("'(1 2 3)").unwrap();
        assert!(matches!(v, Value::List(_)));
    }

    // ── keyword lookup ────────────────────────────────────────────────────

    #[test]
    fn test_keyword_lookup() {
        assert_eq!(eval_str("(:a {:a 1})").unwrap(), long(1));
    }

    #[test]
    fn test_keyword_lookup_missing() {
        assert_eq!(eval_str("(:b {:a 1})").unwrap(), Value::Nil);
    }

    // ── Map / Vector / Set literals ───────────────────────────────────────

    #[test]
    fn test_map_literal() {
        let v = eval_str("{:a 1 :b 2}").unwrap();
        assert!(matches!(v, Value::Map(_)));
        if let Value::Map(m) = &v {
            assert_eq!(m.count(), 2);
        }
    }

    #[test]
    fn test_vector_literal() {
        let v = eval_str("[1 2 3]").unwrap();
        assert!(matches!(v, Value::Vector(_)));
    }

    #[test]
    fn test_set_literal() {
        let v = eval_str("#{1 2 3}").unwrap();
        assert!(matches!(v, Value::Set(_)));
    }

    #[test]
    fn test_contains_q_vector_non_integer_key_returns_false() {
        // Regression for #206: non-integer key on a vector must return false,
        // not throw a WrongType error.
        assert_eq!(eval_str("(contains? [1 2 3] :a)").unwrap(), bool_v(false));
        assert_eq!(
            eval_str("(contains? [1 2 3] \"x\")").unwrap(),
            bool_v(false)
        );
        // Integer keys still work correctly.
        assert_eq!(eval_str("(contains? [1 2 3] 0)").unwrap(), bool_v(true));
        assert_eq!(eval_str("(contains? [1 2 3] 9)").unwrap(), bool_v(false));
    }

    // ── set! ──────────────────────────────────────────────────────────────

    #[test]
    fn test_set_bang() {
        let (_, mut env) = make_env();
        eval_src("(def x 1)", &mut env).unwrap();
        eval_src("(set! x 99)", &mut env).unwrap();
        assert_eq!(eval_src("x", &mut env).unwrap(), long(99));
    }

    // ── throw / try / catch ───────────────────────────────────────────────

    #[test]
    fn test_throw_catch() {
        let v = eval_str("(try (throw (ex-info \"oops\" {})) (catch Exception e (ex-message e)))")
            .unwrap();
        assert!(matches!(v, Value::Str(_)));
    }

    #[test]
    fn test_try_no_throw() {
        assert_eq!(eval_str("(try 42)").unwrap(), long(42));
    }

    #[test]
    fn test_catch_default_catches_internal_value_errors() {
        // Regression for #168: internal `ValueError`s (IndexOutOfBounds, WrongType)
        // raised by core ops must be caught by the ClojureScript `:default` keyword,
        // not just by symbol catch types.
        for src in [
            "(try (nth [1 2 3] 10) (catch :default e \"caught\"))",
            "(try (aget (long-array 3) 10) (catch :default e \"caught\"))",
            "(try (aset (long-array 3) 10 5) (catch :default e \"caught\"))",
        ] {
            let v = eval_str(src).unwrap();
            assert_eq!(v, Value::string("caught"), "{src}");
        }
    }

    #[test]
    fn test_catch_default_binds_clean_ex_message() {
        // The caught value is a normalized exception: `ex-message` returns the
        // plain `ValueError` text with no `runtime error:` prefix, matching how a
        // user `throw` / `ex-info` value behaves.
        let v = eval_str("(try (nth [1 2 3] 10) (catch :default e (ex-message e)))").unwrap();
        assert_eq!(v, Value::string("index out of bounds: 10 >= 3"));
    }

    #[test]
    fn test_finally_runs_and_value_is_discarded() {
        // finally executes for its side effect, but the `try` value is the body's.
        let v = eval_str("(let [a (atom 0)] (try 1 (finally (reset! a 5))) @a)").unwrap();
        assert_eq!(v, long(5));
        assert_eq!(eval_str("(try 1 (finally 2))").unwrap(), long(1));
    }

    #[test]
    fn test_finally_runs_after_catch() {
        let v = eval_str(
            "(let [a (atom 0)]
               (try (throw (ex-info \"x\" {})) (catch Exception e :caught)
                 (finally (reset! a 9)))
               @a)",
        )
        .unwrap();
        assert_eq!(v, long(9));
    }

    #[test]
    fn test_finally_exception_propagates() {
        // An exception thrown from `finally` supersedes the body's result.
        assert!(eval_str("(try 1 (finally (throw (ex-info \"boom\" {}))))").is_err());
    }

    #[test]
    fn test_catch_reader_conditional_type() {
        // Regression for #210: a reader conditional in the catch type position must
        // be resolved before matching — previously the catch clause was silently
        // dropped and the exception escaped.

        // Single-branch: #?(:rust Exception)
        let v =
            eval_str(r#"(try (throw (ex-info "boom" {})) (catch #?(:rust Exception) e :caught))"#)
                .unwrap();
        let kw_caught = Value::keyword(cljrs_value::Keyword::simple("caught"));
        assert_eq!(v, kw_caught, "single-branch reader cond");

        // Multi-branch: the :rust branch must win over :clj/:cljs/:default ordering
        let v = eval_str(concat!(
            "(try (throw (ex-info \"boom\" {})) ",
            "(catch #?(:clj Throwable :cljs :default :rust Exception) e :caught))",
        ))
        .unwrap();
        assert_eq!(v, kw_caught, "multi-branch reader cond");

        // A reader conditional whose :rust branch resolves to :default is also a
        // catch-all and must match any exception.
        let v =
            eval_str(r#"(try (throw (ex-info "boom" {})) (catch #?(:rust :default) e :caught))"#)
                .unwrap();
        assert_eq!(v, kw_caught, "reader cond resolves to :default");

        // A reader conditional with no :rust branch must NOT catch the exception.
        let result =
            eval_str(r#"(try (throw (ex-info "boom" {})) (catch #?(:clj Throwable) e :caught))"#);
        assert!(
            result.is_err(),
            "no matching :rust branch must let exception escape"
        );
    }

    #[test]
    fn test_nth_negative_index() {
        // Negative index returns the not-found default, or throws without one.
        assert_eq!(
            eval_str("(= (nth [10 20 30] -1 :nf) :nf)").unwrap(),
            bool_v(true)
        );
        assert!(eval_str("(nth [10 20 30] -1)").is_err());
        assert!(eval_str("(nth '(1 2 3) -1)").is_err());
        // Crucially, must NOT hang walking an infinite lazy seq to usize::MAX.
        assert_eq!(
            eval_str("(= (nth (range) -1 :nf) :nf)").unwrap(),
            bool_v(true)
        );
        assert_eq!(
            eval_str("(= (nth '(1 2 3) -1 :nf) :nf)").unwrap(),
            bool_v(true)
        );
    }

    // ── destructuring ─────────────────────────────────────────────────────

    #[test]
    fn test_sequential_destructure() {
        assert_eq!(eval_str("(let* [[a b] [1 2]] (+ a b))").unwrap(), long(3));
    }

    #[test]
    fn test_rest_destructure() {
        let v = eval_str("(let* [[h & t] [1 2 3]] t)").unwrap();
        assert!(matches!(v, Value::List(_)));
        if let Value::List(l) = &v {
            assert_eq!(l.get().count(), 2);
        }
    }

    // ── defmacro ──────────────────────────────────────────────────────────

    #[test]
    fn test_defmacro() {
        let (_, mut env) = make_env();
        eval_src("(defmacro my-if [t a b] (list 'if t a b))", &mut env).unwrap();
        assert_eq!(eval_src("(my-if true 1 2)", &mut env).unwrap(), long(1));
        assert_eq!(eval_src("(my-if false 1 2)", &mut env).unwrap(), long(2));
    }

    // ── syntax-quote ──────────────────────────────────────────────────────

    #[test]
    fn test_syntax_quote_basic() {
        let (_, mut env) = make_env();
        eval_src("(def b 2)", &mut env).unwrap();
        let v = eval_src("`(a ~b)", &mut env).unwrap();
        assert!(matches!(v, Value::List(_)));
        if let Value::List(l) = &v {
            // Should be (user/a 2)
            let items: Vec<_> = l.get().iter().cloned().collect();
            assert_eq!(items.len(), 2);
            assert_eq!(items[1], long(2));
        }
    }

    // ── reader conditionals ───────────────────────────────────────────────

    #[test]
    fn test_reader_cond_rust() {
        // :rust branch selected.
        assert_eq!(eval_str("#?(:rust 1 :clj 2)").unwrap(), long(1));
    }

    #[test]
    fn test_reader_cond_default() {
        // No :rust; fall through to :default.
        assert_eq!(eval_str("#?(:clj 2 :default 99)").unwrap(), long(99));
    }

    #[test]
    fn test_reader_cond_splice_in_vector() {
        assert_eq!(
            eval_str("[1 #?@(:rust [:a :b]) 2]").unwrap(),
            eval_str("[1 :a :b 2]").unwrap()
        );
    }

    #[test]
    fn test_reader_cond_splice_in_set() {
        assert_eq!(
            eval_str("#{1 #?@(:rust [2 3]) 4}").unwrap(),
            eval_str("#{1 2 3 4}").unwrap()
        );
    }

    #[test]
    fn test_reader_cond_splice_in_map() {
        assert_eq!(
            eval_str("{:a 1 #?@(:rust [:b 2]) :c 3}").unwrap(),
            eval_str("{:a 1 :b 2 :c 3}").unwrap()
        );
    }

    #[test]
    fn test_reader_cond_splice_in_call_args() {
        assert_eq!(
            eval_str("(vector 1 #?@(:rust [2 3]) 4)").unwrap(),
            eval_str("[1 2 3 4]").unwrap()
        );
    }

    #[test]
    fn test_reader_cond_splice_no_match_removed() {
        assert_eq!(
            eval_str("[1 #?@(:clj [:a :b]) 2]").unwrap(),
            eval_str("[1 2]").unwrap()
        );
    }

    proptest::proptest! {
        #![proptest_config(proptest::prelude::ProptestConfig::with_cases(48))]
        /// Splicing `#?@(:rust mid)` into any container evaluates to the same
        /// value as inlining `mid` literally - for vector, set, data-list, and
        /// call arguments. Elements are distinct so set literals stay legal.
        #[test]
        fn prop_splice_evals_as_inline_in_every_container(
            np in 0usize..3, nm in 0usize..3, ns in 0usize..3,
        ) {
            let kw_run = |start: usize, n: usize| {
                (start..start + n)
                    .map(|i| format!(":v{i}"))
                    .collect::<Vec<_>>()
                    .join(" ")
            };
            let p = kw_run(0, np);
            let m = kw_run(np, nm);
            let s = kw_run(np + nm, ns);
            for (open, close, quote) in
                [("[", "]", ""), ("#{", "}", ""), ("(", ")", "'"), ("(vector ", ")", "")]
            {
                let spliced = format!("{quote}{open}{p} #?@(:rust [{m}]) {s}{close}");
                let inlined = format!("{quote}{open}{p} {m} {s}{close}");
                proptest::prop_assert_eq!(
                    eval_str(&spliced).unwrap(),
                    eval_str(&inlined).unwrap(),
                    "container {}{}",
                    open,
                    close
                );
            }
        }
    }

    // ── Reader conditionals: cross-path and binding-vector properties ─────
    //
    // One generated position in a container or binding vector. Names are
    // assigned by index, so generated elements are distinct and set literals
    // stay legal.

    #[derive(Clone, Debug)]
    enum Slot {
        /// A plain element; contributes 1.
        Plain,
        /// `#?(…)`; contributes 1 when the branch key matches, else 0.
        NonSplice { matches: bool },
        /// `#?@(…)`; contributes `n` when the branch key matches, else 0.
        Splice { matches: bool, n: usize },
    }

    fn slot_strat() -> impl proptest::strategy::Strategy<Value = Slot> {
        use proptest::strategy::{Just, Strategy};
        proptest::prop_oneof![
            Just(Slot::Plain),
            proptest::bool::ANY.prop_map(|matches| Slot::NonSplice { matches }),
            (proptest::bool::ANY, 0usize..3).prop_map(|(matches, n)| Slot::Splice { matches, n }),
        ]
    }

    /// Render `slots` twice - conditionals written out, and branches inlined -
    /// with `unit` forms per contributed position. `unit(i)` renders element
    /// `i`; a unit of two tokens (`x0 0`) keeps pair parity even, which is what
    /// binding vectors need.
    fn render_slots(slots: &[Slot], unit: &dyn Fn(usize) -> String) -> (String, String) {
        let mut next = 0usize;
        let (mut written, mut inlined) = (Vec::new(), Vec::new());
        for slot in slots {
            match *slot {
                Slot::Plain => {
                    let u = unit(next);
                    next += 1;
                    written.push(u.clone());
                    inlined.push(u);
                }
                Slot::NonSplice { matches } => {
                    let u = unit(next);
                    next += 1;
                    let key = if matches { "rust" } else { "clj" };
                    written.push(format!("#?(:{key} {u})"));
                    if matches {
                        inlined.push(u);
                    }
                }
                Slot::Splice { matches, n } => {
                    let us: Vec<String> = (0..n)
                        .map(|_| {
                            let u = unit(next);
                            next += 1;
                            u
                        })
                        .collect();
                    let key = if matches { "rust" } else { "clj" };
                    written.push(format!("#?@(:{key} [{}])", us.join(" ")));
                    if matches {
                        inlined.extend(us);
                    }
                }
            }
        }
        (written.join(" "), inlined.join(" "))
    }

    /// Binding vectors take pairs, and a non-splicing `#?` selects exactly one
    /// form - so it cannot carry a `name init` pair. Only plain positions and
    /// `#?@` splices can appear there.
    fn pair_slot_strat() -> impl proptest::strategy::Strategy<Value = Slot> {
        use proptest::strategy::{Just, Strategy};
        proptest::prop_oneof![
            Just(Slot::Plain),
            (proptest::bool::ANY, 0usize..3).prop_map(|(matches, n)| Slot::Splice { matches, n }),
        ]
    }

    fn kw_unit(i: usize) -> String {
        format!(":k{i}")
    }

    /// `x<i> <i>` - one binding pair, so every contributed position keeps the
    /// vector's parity even.
    fn binding_unit(i: usize) -> String {
        format!("x{i} {i}")
    }

    proptest::proptest! {
        #![proptest_config(proptest::prelude::ProptestConfig::with_cases(48))]

        /// A form's meaning must not depend on which path reads it. For the same
        /// container, evaluating it, quoting it, and syntax-quoting it all agree
        /// with the hand-inlined spelling. Before this fix the quoted and
        /// syntax-quoted paths dropped or nil-filled splices that the evaluated
        /// path expanded.
        #[test]
        fn prop_splice_agrees_across_eval_quote_and_syntax_quote(
            slots in proptest::collection::vec(slot_strat(), 0..5),
        ) {
            let (written, inlined) = render_slots(&slots, &kw_unit);
            let even = inlined.split_whitespace().count().is_multiple_of(2);
            for (open, close) in [("[", "]"), ("#{", "}"), ("{", "}")] {
                if open == "{" && !even {
                    continue;
                }
                for prefix in ["", "'", "`"] {
                    let got = eval_str(&format!("{prefix}{open}{written}{close}"));
                    let want = eval_str(&format!("{prefix}{open}{inlined}{close}"));
                    proptest::prop_assert_eq!(
                        got.map_err(|e| e.to_string()),
                        want.map_err(|e| e.to_string()),
                        "prefix {:?} container {}{}", prefix, open, close
                    );
                }
            }
            // Data lists have no evaluated spelling; check both quoted forms.
            for prefix in ["'", "`"] {
                let got = eval_str(&format!("{prefix}({written})"));
                let want = eval_str(&format!("{prefix}({inlined})"));
                proptest::prop_assert_eq!(
                    got.map_err(|e| e.to_string()),
                    want.map_err(|e| e.to_string()),
                    "prefix {:?} list", prefix
                );
            }
        }

        /// Every binding vector resolves conditionals: `let*`, `loop*` and
        /// `binding` bind exactly what the inlined spelling binds.
        #[test]
        fn prop_splice_in_binding_vectors_equals_inline(
            slots in proptest::collection::vec(pair_slot_strat(), 0..4),
        ) {
            let (written, inlined) = render_slots(&slots, &binding_unit);
            let names: Vec<String> = inlined
                .split_whitespace()
                .step_by(2)
                .map(str::to_string)
                .collect();
            let body = format!("[{}]", names.join(" "));
            for head in ["let*", "loop*"] {
                let got = eval_str(&format!("({head} [{written}] {body})"));
                let want = eval_str(&format!("({head} [{inlined}] {body})"));
                proptest::prop_assert_eq!(
                    got.map_err(|e| e.to_string()),
                    want.map_err(|e| e.to_string()),
                    "{}", head
                );
            }
        }
    }

    #[test]
    fn quoted_map_splice_lands_in_key_value_positions() {
        assert_eq!(
            eval_str("'{:a 1 #?@(:rust [:b 2]) :c 3}").unwrap(),
            eval_str("{:a 1 :b 2 :c 3}").unwrap()
        );
    }

    #[test]
    fn syntax_quoted_splice_is_expanded_not_nil() {
        assert_eq!(
            eval_str("`(1 #?@(:rust [2 3]) 4)").unwrap(),
            eval_str("'(1 2 3 4)").unwrap()
        );
    }

    #[test]
    fn map_literal_with_only_an_unmatched_conditional_reads_as_empty() {
        // The written parity is odd, the expansion is empty - the reader must
        // defer rather than reject.
        assert_eq!(eval_str("{#?(:clj :a)}").unwrap(), eval_str("{}").unwrap());
    }

    #[test]
    fn loop_binding_vector_expands_splices() {
        assert_eq!(eval_str("(loop* [#?@(:rust [x 1])] x)").unwrap(), long(1));
    }

    // ── Error cases ───────────────────────────────────────────────────────

    #[test]
    fn test_unbound_symbol() {
        let r = eval_str("undefined-var-xyz");
        assert!(matches!(r, Err(EvalError::UnboundSymbol(_))));
    }

    #[test]
    fn test_wrong_arity() {
        let (_, mut env) = make_env();
        eval_src("(defn one-arg [x] x)", &mut env).unwrap();
        let r = eval_src("(one-arg 1 2)", &mut env);
        assert!(matches!(r, Err(EvalError::Arity { .. })));
    }

    #[test]
    fn test_not_callable() {
        let r = eval_str("(42 1 2)");
        assert!(matches!(r, Err(EvalError::NotCallable(_))));
    }

    // ── Higher-order functions (bootstrap) ────────────────────────────────

    #[test]
    fn test_map_fn() {
        assert_eq!(
            eval_str("(vec (map inc [1 2 3]))").unwrap(),
            eval_str("[2 3 4]").unwrap()
        );
    }

    #[test]
    fn test_filter_fn() {
        assert_eq!(
            eval_str("(vec (filter odd? [1 2 3 4 5]))").unwrap(),
            eval_str("[1 3 5]").unwrap()
        );
    }

    #[test]
    fn test_reduce_fn() {
        assert_eq!(eval_str("(reduce + [1 2 3 4 5])").unwrap(), long(15));
    }

    #[test]
    fn test_apply_fn() {
        assert_eq!(eval_str("(apply + [1 2 3])").unwrap(), long(6));
    }

    #[test]
    fn test_atom_ops() {
        let (_, mut env) = make_env();
        eval_src("(def a (atom 0))", &mut env).unwrap();
        eval_src("(swap! a inc)", &mut env).unwrap();
        assert_eq!(eval_src("(deref a)", &mut env).unwrap(), long(1));
    }

    #[test]
    fn test_when_macro() {
        assert_eq!(eval_str("(when true 42)").unwrap(), long(42));
        assert_eq!(eval_str("(when false 42)").unwrap(), Value::Nil);
    }

    #[test]
    fn test_cond_macro() {
        assert_eq!(eval_str("(cond false 1 true 2)").unwrap(), long(2));
    }

    #[test]
    fn test_and_or() {
        assert_eq!(eval_str("(and 1 2 3)").unwrap(), long(3));
        assert_eq!(eval_str("(and 1 false 3)").unwrap(), bool_v(false));
        assert_eq!(eval_str("(or false nil 42)").unwrap(), long(42));
        assert_eq!(eval_str("(or false nil)").unwrap(), Value::Nil);
    }

    // ── Phase 5: Lazy sequences ───────────────────────────────────────────

    #[test]
    fn test_lazy_range() {
        assert_eq!(
            eval_str("(= (into [] (take 5 (range))) [0 1 2 3 4])").unwrap(),
            bool_v(true)
        );
    }

    #[test]
    fn test_lazy_range_bounded() {
        assert_eq!(
            eval_str("(= (into [] (range 3)) [0 1 2])").unwrap(),
            bool_v(true)
        );
    }

    #[test]
    fn test_lazy_iterate() {
        assert_eq!(
            eval_str("(= (into [] (take 3 (iterate inc 0))) [0 1 2])").unwrap(),
            bool_v(true)
        );
    }

    #[test]
    fn test_lazy_repeat() {
        assert_eq!(
            eval_str("(= (into [] (take 3 (repeat :x))) [:x :x :x])").unwrap(),
            bool_v(true)
        );
    }

    #[test]
    fn test_lazy_cycle() {
        assert_eq!(
            eval_str("(= (into [] (take 5 (cycle [1 2]))) [1 2 1 2 1])").unwrap(),
            bool_v(true)
        );
    }

    // ── Phase 5: Associative destructuring ───────────────────────────────

    #[test]
    fn test_assoc_destructure() {
        assert_eq!(
            eval_str("(let [{:keys [a b]} {:a 1 :b 2}] (+ a b))").unwrap(),
            long(3)
        );
    }

    #[test]
    fn test_assoc_destructure_or() {
        assert_eq!(
            eval_str("(let [{:keys [a b] :or {b 99}} {:a 1}] b)").unwrap(),
            long(99)
        );
    }

    // ── Phase 5: letfn ───────────────────────────────────────────────────

    #[test]
    fn test_letfn() {
        assert_eq!(
            eval_str("(letfn [(fact [n] (if (= n 0) 1 (* n (fact (dec n)))))] (fact 5))").unwrap(),
            long(120)
        );
    }

    // ── Phase 5: namespace ops ────────────────────────────────────────────

    #[test]
    fn test_in_ns() {
        let (_, mut env) = make_env();
        eval_src("(in-ns 'mytest)", &mut env).unwrap();
        assert_eq!(env.current_ns.as_ref(), "mytest");
        eval_src("(in-ns 'user)", &mut env).unwrap();
        assert_eq!(env.current_ns.as_ref(), "user");
    }

    // ── Phase 5: spit / slurp ─────────────────────────────────────────────

    #[test]
    fn test_spit_slurp() {
        let path = std::env::temp_dir().join("cljrs_test_spit_slurp.txt");
        let path_str = path.to_str().unwrap();
        let src = format!(
            r#"(do (spit "{}" "hello clojurust") (slurp "{}"))"#,
            path_str, path_str
        );
        let result = eval_str(&src).unwrap();
        if let Value::Str(s) = result {
            assert_eq!(s.get().as_str(), "hello clojurust");
        } else {
            panic!("expected string result from slurp");
        }
        let _ = std::fs::remove_file(path);
    }

    // ── Phase 5: update-in ───────────────────────────────────────────────

    #[test]
    fn test_update_in() {
        assert_eq!(
            eval_str("(= (update-in {:a {:b 1}} [:a :b] inc) {:a {:b 2}})").unwrap(),
            bool_v(true)
        );
    }

    // ── Phase 5: if-let / when-let ────────────────────────────────────────

    #[test]
    fn test_if_let_truthy() {
        assert_eq!(eval_str("(if-let [x 42] x :nope)").unwrap(), long(42));
    }

    #[test]
    fn test_if_let_falsy() {
        assert_eq!(
            eval_str("(if-let [x nil] x :nope)").unwrap(),
            eval_str(":nope").unwrap()
        );
    }

    #[test]
    fn test_when_let_truthy() {
        assert_eq!(eval_str("(when-let [x 7] (* x 2))").unwrap(), long(14));
    }

    #[test]
    fn test_when_let_falsy() {
        assert_eq!(eval_str("(when-let [x nil] 99)").unwrap(), Value::Nil);
    }

    // ── Phase 5: math functions ───────────────────────────────────────────

    #[test]
    fn test_math_trig() {
        // sin(0) = 0, cos(0) = 1
        assert_eq!(eval_str("(Math/sin 0)").unwrap(), Value::Double(0.0));
        assert_eq!(eval_str("(Math/cos 0)").unwrap(), Value::Double(1.0));
    }

    #[test]
    fn test_math_constants() {
        assert!(
            matches!(eval_str("Math/PI").unwrap(), Value::Double(v) if (v - std::f64::consts::PI).abs() < 1e-10)
        );
        assert!(
            matches!(eval_str("Math/E").unwrap(), Value::Double(v) if (v - std::f64::consts::E).abs() < 1e-10)
        );
    }

    #[test]
    fn test_math_log_exp() {
        // exp(0) = 1, log(1) = 0
        assert_eq!(eval_str("(Math/exp 0)").unwrap(), Value::Double(1.0));
        assert_eq!(eval_str("(Math/log 1)").unwrap(), Value::Double(0.0));
    }

    // ── Phase 6: Protocols & Multimethods ─────────────────────────────────

    #[test]
    fn test_defprotocol() {
        // Defining a protocol creates a callable ProtocolFn that errors without impl.
        let result = eval_str(
            r#"
            (defprotocol Greet
              (greet [this]))
            (greet "hello")
            "#,
        );
        assert!(result.is_err());
        let msg = result.unwrap_err().to_string();
        assert!(msg.contains("No implementation"), "got: {msg}");
    }

    #[test]
    fn test_extend_type() {
        let result = eval_str(
            r#"
            (defprotocol Greet
              (greet [this]))
            (extend-type String
              Greet
              (greet [this] (str "Hello, " this "!")))
            (greet "world")
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::string("Hello, world!"));
    }

    #[test]
    fn test_protocol_dispatch() {
        let result = eval_str(
            r#"
            (defprotocol Describable
              (describe [this]))
            (extend-type String
              Describable
              (describe [this] (str "string:" this)))
            (extend-type Long
              Describable
              (describe [this] (str "long:" this)))
            [(describe "hi") (describe 42)]
            "#,
        )
        .unwrap();
        assert!(matches!(result, Value::Vector(_)));
        let s = format!("{}", result);
        assert!(s.contains("string:hi"), "got: {s}");
        assert!(s.contains("long:42"), "got: {s}");
    }

    #[test]
    fn test_extend_protocol() {
        let result = eval_str(
            r#"
            (defprotocol Showable
              (show [this]))
            (extend-protocol Showable
              String
              (show [this] (str "S:" this))
              Long
              (show [this] (str "L:" this)))
            [(show "x") (show 7)]
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.contains("S:x"), "got: {s}");
        assert!(s.contains("L:7"), "got: {s}");
    }

    #[test]
    fn test_extend_via_metadata() {
        // `:extend-via-metadata true` lets an instance implement a protocol by
        // carrying the impl fn in its own metadata, keyed by the protocol
        // method's fully-qualified symbol (matching real Clojure's
        // `MethodImplCache` dispatch, which looks up `(.sym cache)` in
        // `(meta x)`) — no `extend-type`/`extend-protocol` needed. Idiomatic
        // usage produces that qualified symbol via syntax-quote.
        let result = eval_str(
            r#"
            (defprotocol IRender
              :extend-via-metadata true
              (create-element [this tag-name]))
            (def renderer (with-meta {} {`create-element (fn [this tag-name] (str "made-" tag-name))}))
            (create-element renderer "div")
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::string("made-div"));
    }

    #[test]
    fn test_extend_via_metadata_falls_back_to_type_tag() {
        // Metadata impls take priority, but a value without metadata still
        // dispatches on its type tag as usual.
        let result = eval_str(
            r#"
            (defprotocol IRender
              :extend-via-metadata true
              (create-element [this tag-name]))
            (extend-type Map
              IRender
              (create-element [this tag-name] (str "type-tag-" tag-name)))
            [(create-element {} "span")
             (create-element (with-meta {} {`create-element (fn [this tag-name] (str "meta-" tag-name))}) "div")]
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.contains("type-tag-span"), "got: {s}");
        assert!(s.contains("meta-div"), "got: {s}");
    }

    #[test]
    fn test_extend_via_metadata_cross_ns() {
        // Mirrors Replicant's mutation_log fake renderer: `IRender` is
        // defined in `replicant.core`, and a test namespace `:refer`s the
        // method and implements it purely via metadata (no `extend-type`).
        // Syntax-quoting `create-element` there must resolve to the
        // protocol's home namespace (`replicant.core/create-element`), which
        // is exactly the key the dispatcher looks up.
        let dir = temp_ns_dir("extend_via_metadata_cross_ns");
        std::fs::create_dir_all(dir.join("replicant")).unwrap();
        std::fs::write(
            dir.join("replicant").join("core.cljrs"),
            r#"(ns replicant.core)
               (defprotocol IRender
                 :extend-via-metadata true
                 (create-element [this tag-name]))"#,
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src(
            r#"
            (ns mutation-log-test
              (:require [replicant.core :refer [create-element]]))
            (def renderer (with-meta {} {`create-element (fn [this tag-name] (str "made-" tag-name))}))
            (create-element renderer "div")
            "#,
            &mut env,
        )
        .unwrap();
        assert_eq!(result, Value::string("made-div"));
    }

    #[test]
    fn test_extend_via_metadata_cross_ns_via_alias() {
        // The `:refer` case above never touches the buggy path: a `:refer`d
        // bare symbol resolves through `lookup_var_in_ns`, which was always
        // correct. Real usage syntax-quotes an *aliased* symbol instead —
        // `` `p/attached? `` — which used to hit `qualify_symbol`'s "already
        // has a slash, keep as-is" branch and leak the alias text (`p/...`)
        // into the produced symbol instead of resolving it to the protocol's
        // home namespace (`replicant.protocols/...`), so the metadata key
        // never matched.
        let dir = temp_ns_dir("extend_via_metadata_cross_ns_via_alias");
        std::fs::create_dir_all(dir.join("replicant")).unwrap();
        std::fs::write(
            dir.join("replicant").join("protocols.cljrs"),
            r#"(ns replicant.protocols)
               (defprotocol IRender
                 :extend-via-metadata true
                 (attached? [this el]))"#,
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src(
            r#"
            (ns mutation-log-test
              (:require [replicant.protocols :as p]))
            (def r (with-meta {:log []} {`p/attached? (fn [_ el] el)}))
            (p/attached? r :el)
            "#,
            &mut env,
        )
        .unwrap();
        assert_eq!(result, Value::keyword(Keyword::simple("el")));
    }

    #[test]
    fn test_satisfies() {
        let result = eval_str(
            r#"
            (defprotocol Animal
              (speak [this]))
            (extend-type String
              Animal
              (speak [this] this))
            [(satisfies? Animal "dog") (satisfies? Animal 42)]
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.contains("true"), "got: {s}");
        assert!(s.contains("false"), "got: {s}");
    }

    #[test]
    fn test_defmulti_defmethod() {
        // Note: fn param destructuring not yet supported; use explicit map lookups.
        let result = eval_str(
            r#"
            (defmulti area :shape)
            (defmethod area :circle [m] (* 3 (:r m) (:r m)))
            (defmethod area :rectangle [m] (* (:w m) (:h m)))
            [(area {:shape :circle :r 2}) (area {:shape :rectangle :w 3 :h 4})]
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        // circle: 3*2*2=12, rectangle: 3*4=12
        assert!(s.contains("12"), "got: {s}");
    }

    #[test]
    fn test_default_dispatch() {
        let result = eval_str(
            r#"
            (defmulti classify :kind)
            (defmethod classify :default [x] :unknown)
            (defmethod classify :cat [x] :meow)
            [(classify {:kind :dog}) (classify {:kind :cat})]
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.contains(":unknown"), "got: {s}");
        assert!(s.contains(":meow"), "got: {s}");
    }

    #[test]
    fn test_prefer_method() {
        // prefer-method shouldn't error; just records preference
        let result = eval_str(
            r#"
            (defmulti foo identity)
            (defmethod foo :a [x] 1)
            (prefer-method foo :a :b)
            (foo :a)
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::Long(1));
    }

    #[test]
    fn test_remove_method() {
        let result = eval_str(
            r#"
            (defmulti bar identity)
            (defmethod bar :x [_] 99)
            (remove-method bar :x)
            (bar :x)
            "#,
        );
        assert!(result.is_err());
        let msg = result.unwrap_err().to_string();
        assert!(msg.contains("No method"), "got: {msg}");
    }

    // ── Phase 7: Concurrency primitives ──────────────────────────────────────

    #[test]
    fn test_compare_and_set() {
        let result = eval_str(
            r#"
            (let [a (atom 10)]
              [(compare-and-set! a 10 20)   ; succeeds: 10 == 10
               (compare-and-set! a 10 30)   ; fails:    20 != 10
               @a])
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.contains("true"), "got: {s}");
        assert!(s.contains("false"), "got: {s}");
        assert!(s.contains("20"), "got: {s}");
    }

    #[test]
    fn test_volatile() {
        let result = eval_str(
            r#"
            (let [v (volatile! 1)]
              (vreset! v 2)
              (vswap! v + 10)
              @v)
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::Long(12));
    }

    #[test]
    fn test_delay() {
        // Body should not be evaluated until forced.
        let result = eval_str(
            r#"
            (let [calls (atom 0)
                  d (delay (swap! calls inc) 42)]
              [@calls (force d) @calls (force d) @calls])
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        // calls starts at 0, force evaluates body once (returns 42), second force uses cache
        // s = [0 42 1 42 1]
        assert!(s.starts_with("[0 42 1 42 1]"), "got: {s}");
    }

    #[test]
    fn test_realized() {
        let result = eval_str(
            r#"
            (let [d (delay 99)]
              [(realized? d) (force d) (realized? d)])
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        assert!(s.starts_with("[false 99 true]"), "got: {s}");
    }

    #[test]
    fn test_promise() {
        let result = eval_str(
            r#"
            (let [p (promise)]
              (deliver p 42)
              (deliver p 99)  ; second deliver is ignored
              @p)
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::Long(42));
    }

    #[test]
    #[ignore = "future/thread spawn not yet implemented (Phase A1 — GcPtr: !Send)"]
    fn test_future() {
        let result = eval_str(
            r#"
            (let [f (future (+ 1 2))]
              @f)
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::Long(3));
    }

    #[test]
    #[ignore = "agent not yet implemented (Phase A1 — GcPtr: !Send)"]
    fn test_agent_send() {
        let result = eval_str(
            r#"
            (let [a (agent 0)]
              (send a + 1)
              (send a + 2)
              (await-agent a)
              @a)
            "#,
        )
        .unwrap();
        assert_eq!(result, Value::Long(3));
    }

    #[test]
    #[ignore = "agent not yet implemented (Phase A1 — GcPtr: !Send)"]
    fn test_agent_error_restart() {
        let result = eval_str(
            r#"
            (let [a (agent 10)]
              (send a (fn [_] (throw (ex-info "boom" {}))))
              (await-agent a)
              (let [err (agent-error a)]
                (restart-agent a 99)
                [err @a]))
            "#,
        )
        .unwrap();
        let s = format!("{}", result);
        // err should be a string containing "boom", @a should be 99
        assert!(s.contains("boom"), "got: {s}");
        assert!(s.contains("99"), "got: {s}");
    }

    #[test]
    fn test_defrecord_basic() {
        // Constructor and field access via keyword.
        let result = eval_str(
            r#"
            (defrecord Point [x y])
            (let [p (->Point 3 4)]
              [(:x p) (:y p)])
            "#,
        )
        .unwrap();
        assert_eq!(result.to_string(), "[3 4]");
    }

    #[test]
    fn test_defrecord_map_constructor() {
        let result = eval_str(
            r#"
            (defrecord Color [r g b])
            (let [c (map->Color {:r 255 :g 128 :b 0})]
              [(:r c) (:g c) (:b c)])
            "#,
        )
        .unwrap();
        assert_eq!(result.to_string(), "[255 128 0]");
    }

    #[test]
    fn test_defrecord_assoc() {
        // assoc on a record returns a new record of the same type.
        let result = eval_str(
            r#"
            (defrecord Pt [x y])
            (let [p (->Pt 1 2)
                  q (assoc p :x 99)]
              [(:x q) (:y q) (record? q)])
            "#,
        )
        .unwrap();
        assert_eq!(result.to_string(), "[99 2 true]");
    }

    #[test]
    fn test_defrecord_with_protocol() {
        let result = eval_str(
            r#"
            (defprotocol IShape
              (area [this]))
            (defrecord Circle [radius]
              IShape
              (area [this] (* 3 (:radius this) (:radius this))))
            (let [c (->Circle 5)]
              (area c))
            "#,
        )
        .unwrap();
        assert_eq!(result, cljrs_value::Value::Long(75));
    }

    #[test]
    fn test_instance_q() {
        let result = eval_str(
            r#"
            (defrecord Dog [name])
            (let [d (->Dog "Rex")]
              [(instance? Dog d) (instance? Dog 42)])
            "#,
        )
        .unwrap();
        assert_eq!(result.to_string(), "[true false]");
    }

    #[test]
    fn test_reify_basic() {
        let result = eval_str(
            r#"
            (defprotocol IGreet
              (greet [this name]))
            (let [greeter (reify IGreet
                            (greet [this name] (str "Hello, " name "!")))]
              (greet greeter "World"))
            "#,
        )
        .unwrap();
        assert_eq!(result.to_string(), "\"Hello, World!\"");
    }

    // ── require / load-file ───────────────────────────────────────────────

    fn temp_ns_dir(test_name: &str) -> std::path::PathBuf {
        let dir = std::env::temp_dir().join(format!("cljrs_test_{test_name}"));
        let _ = std::fs::remove_dir_all(&dir);
        std::fs::create_dir_all(&dir).unwrap();
        dir
    }

    fn make_env_with_paths(paths: Vec<std::path::PathBuf>) -> (Arc<GlobalEnv>, Env) {
        use crate::interp::standard_env_with_paths;
        let globals = standard_env_with_paths(None, None, None, paths);
        let env = Env::new(globals.clone(), "user");
        (globals, env)
    }

    #[test]
    fn test_require_as() {
        let dir = temp_ns_dir("require_as");
        std::fs::write(
            dir.join("mylib.cljrs"),
            "(ns mylib) (defn greet [n] (str \"hello \" n))",
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src("(require '[mylib :as ml]) (ml/greet \"world\")", &mut env).unwrap();
        assert_eq!(result.to_string(), "\"hello world\"");
    }

    #[test]
    fn test_require_refer() {
        let dir = temp_ns_dir("require_refer");
        std::fs::write(
            dir.join("myutil.cljrs"),
            "(ns myutil) (defn twice [x] (* 2 x))",
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src("(require '[myutil :refer [twice]]) (twice 21)", &mut env).unwrap();
        assert_eq!(result, Value::Long(42));
    }

    #[test]
    fn test_require_refer_all() {
        let dir = temp_ns_dir("require_refer_all");
        std::fs::write(
            dir.join("mymath.cljrs"),
            "(ns mymath) (defn square [x] (* x x))",
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src("(require '[mymath :refer :all]) (square 7)", &mut env).unwrap();
        assert_eq!(result, Value::Long(49));
    }

    #[test]
    fn test_ns_require_clause() {
        let dir = temp_ns_dir("ns_require");
        std::fs::write(
            dir.join("greeter.cljrs"),
            "(ns greeter) (defn hi [n] (str \"Hi \" n))",
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src(
            "(ns myapp (:require [greeter :as g])) (g/hi \"Alice\")",
            &mut env,
        )
        .unwrap();
        assert_eq!(result.to_string(), "\"Hi Alice\"");
    }

    #[test]
    fn test_var_quote_alias_resolution() {
        // #'alias/sym must resolve the alias to the full namespace, just like
        // a regular function call does (issue #187).
        let dir = temp_ns_dir("var_quote_alias");
        // lib.core maps to lib/core.cljrs on the source path.
        std::fs::create_dir_all(dir.join("lib")).unwrap();
        std::fs::write(
            dir.join("lib/core.cljrs"),
            "(ns lib.core) (defn public [x] (* x 2))",
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        // Regular call via alias must work first.
        let call_result = eval_src("(require '[lib.core :as l]) (l/public 21)", &mut env).unwrap();
        assert_eq!(call_result, Value::Long(42));
        // #'alias/sym reader form.
        let var_result = eval_src("#'l/public", &mut env).unwrap();
        assert!(
            matches!(var_result, Value::Var(_)),
            "expected Var, got {var_result:?}"
        );
        assert_eq!(var_result.to_string(), "#'lib.core/public");
        // (var alias/sym) special form must also resolve the alias.
        let var_special = eval_src("(var l/public)", &mut env).unwrap();
        assert_eq!(var_special.to_string(), "#'lib.core/public");
    }

    #[test]
    fn test_require_idempotent() {
        let dir = temp_ns_dir("require_idempotent");
        // File has a side effect tracked via an atom
        std::fs::write(
            dir.join("counter.cljrs"),
            "(ns counter) (def loaded-count (atom 0)) (swap! loaded-count inc)",
        )
        .unwrap();
        let (globals, mut env) = make_env_with_paths(vec![dir]);
        eval_src("(require 'counter)", &mut env).unwrap();
        eval_src("(require 'counter)", &mut env).unwrap();
        // The atom should have been incremented only once.
        let count = globals.lookup_in_ns("counter", "loaded-count").unwrap();
        if let Value::Atom(a) = count {
            assert_eq!(a.get().deref(), Value::Long(1));
        } else {
            panic!("expected atom");
        }
    }

    #[test]
    fn test_require_not_found() {
        let (_, mut env) = make_env_with_paths(vec![]);
        let err = eval_src("(require 'nonexistent.ns)", &mut env).unwrap_err();
        let msg = format!("{err:?}");
        assert!(msg.contains("nonexistent.ns"), "unexpected error: {msg}");
    }

    #[test]
    fn test_require_circular() {
        let dir = temp_ns_dir("require_circular");
        // a requires b, b requires a
        std::fs::write(dir.join("cira.cljrs"), "(ns cira (:require [cirb]))").unwrap();
        std::fs::write(dir.join("cirb.cljrs"), "(ns cirb (:require [cira]))").unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let err = eval_src("(require 'cira)", &mut env).unwrap_err();
        let msg = format!("{err:?}");
        assert!(
            msg.contains("circular"),
            "expected circular error, got: {msg}"
        );
    }

    #[test]
    fn test_load_file() {
        let dir = temp_ns_dir("load_file");
        let path = dir.join("script.cljrs");
        std::fs::write(&path, "(+ 1 2)").unwrap();
        let (_, mut env) = make_env_with_paths(vec![]);
        let result = eval_src(&format!("(load-file \"{}\")", path.display()), &mut env).unwrap();
        assert_eq!(result, Value::Long(3));
    }

    // ── *ns* and namespace reflection ─────────────────────────────────────────

    #[test]
    fn test_star_ns_initial() {
        // After standard_env(), *ns* should be the user namespace.
        let (_, mut env) = make_env();
        let v = eval_src("*ns*", &mut env).unwrap();
        match v {
            Value::Namespace(ns) => assert_eq!(ns.get().name.as_ref(), "user"),
            other => panic!("expected Namespace, got {other:?}"),
        }
    }

    #[test]
    fn test_star_ns_after_in_ns() {
        let (_, mut env) = make_env();
        eval_src("(in-ns 'myns)", &mut env).unwrap();
        let v = eval_src("*ns*", &mut env).unwrap();
        match v {
            Value::Namespace(ns) => assert_eq!(ns.get().name.as_ref(), "myns"),
            other => panic!("expected Namespace, got {other:?}"),
        }
    }

    #[test]
    fn test_star_ns_after_ns_form() {
        let (_, mut env) = make_env();
        eval_src("(ns mytest.ns)", &mut env).unwrap();
        let v = eval_src("*ns*", &mut env).unwrap();
        match v {
            Value::Namespace(ns) => assert_eq!(ns.get().name.as_ref(), "mytest.ns"),
            other => panic!("expected Namespace, got {other:?}"),
        }
    }

    #[test]
    fn test_ns_name() {
        let (_, mut env) = make_env();
        let v = eval_src("(ns-name *ns*)", &mut env).unwrap();
        match v {
            Value::Symbol(s) => assert_eq!(s.get().name.as_ref(), "user"),
            other => panic!("expected Symbol, got {other:?}"),
        }
    }

    #[test]
    fn test_find_ns() {
        let (_, mut env) = make_env();
        // known ns
        let v = eval_src("(find-ns 'user)", &mut env).unwrap();
        assert!(matches!(v, Value::Namespace(_)));
        // unknown ns
        let v2 = eval_src("(find-ns 'nonexistent)", &mut env).unwrap();
        assert_eq!(v2, Value::Nil);
    }

    #[test]
    fn test_all_ns() {
        let (_, mut env) = make_env();
        let v = eval_src("(all-ns)", &mut env).unwrap();
        // Should be a list containing at least user and clojure.core
        let names: Vec<String> = match &v {
            Value::List(l) => l
                .get()
                .iter()
                .filter_map(|ns| match ns {
                    Value::Namespace(n) => Some(n.get().name.as_ref().to_string()),
                    _ => None,
                })
                .collect(),
            other => panic!("expected list, got {other:?}"),
        };
        assert!(names.contains(&"user".to_string()));
        assert!(names.contains(&"clojure.core".to_string()));
    }

    #[test]
    fn test_ns_interns() {
        let (_, mut env) = make_env();
        eval_src("(def my-test-var 42)", &mut env).unwrap();
        let v = eval_src("(ns-interns *ns*)", &mut env).unwrap();
        let Value::Map(m) = v else {
            panic!("expected map")
        };
        // The map should contain 'my-test-var
        let sym = Value::symbol(cljrs_value::Symbol::simple("my-test-var"));
        assert!(m.get(&sym).is_some());
    }

    #[test]
    fn test_create_ns() {
        let (_, mut env) = make_env();
        let v = eval_src("(create-ns 'fresh.ns)", &mut env).unwrap();
        match v {
            Value::Namespace(ns) => assert_eq!(ns.get().name.as_ref(), "fresh.ns"),
            other => panic!("expected Namespace, got {other:?}"),
        }
        // find-ns should now find it
        let v2 = eval_src("(find-ns 'fresh.ns)", &mut env).unwrap();
        assert!(matches!(v2, Value::Namespace(_)));
    }

    // ── Dynamic variables (Phase 9) ───────────────────────────────────────────

    #[test]
    fn test_dynamic_var_basic() {
        let (globals, mut env) = make_env();
        let result = eval_src("(def ^:dynamic *x* 10) (binding [*x* 42] *x*)", &mut env).unwrap();
        assert_eq!(result, Value::Long(42));
        // verify root is still bound
        let root = globals.lookup_in_ns("user", "*x*");
        assert_eq!(root, Some(Value::Long(10)));
    }

    #[test]
    fn test_dynamic_var_restore() {
        let (_globals, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 10)", &mut env).unwrap();
        eval_src("(binding [*x* 42] *x*)", &mut env).unwrap();
        // After binding block, value restored to root
        let val = eval_src("*x*", &mut env).unwrap();
        assert_eq!(val, Value::Long(10));
    }

    #[test]
    fn test_dynamic_var_nested() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 1)", &mut env).unwrap();
        let result = eval_src("(binding [*x* 2] (binding [*x* 3] *x*))", &mut env).unwrap();
        assert_eq!(result, Value::Long(3));
        // After both blocks
        let val = eval_src("*x*", &mut env).unwrap();
        assert_eq!(val, Value::Long(1));
    }

    #[test]
    fn test_dynamic_var_unaffected() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 10)", &mut env).unwrap();
        eval_src("(def y 99)", &mut env).unwrap();
        eval_src("(binding [*x* 42] *x*)", &mut env).unwrap();
        // non-dynamic var y is unchanged
        let val = eval_src("y", &mut env).unwrap();
        assert_eq!(val, Value::Long(99));
    }

    #[test]
    #[ignore = "future/thread spawn not yet implemented (Phase A1 — GcPtr: !Send)"]
    fn test_binding_conveyance() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 10)", &mut env).unwrap();
        let result = eval_src("(binding [*x* 42] @(future *x*))", &mut env).unwrap();
        assert_eq!(result, Value::Long(42));
    }

    #[test]
    fn test_var_set_in_binding() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 10)", &mut env).unwrap();
        // set! inside binding sets thread-local
        let inside = eval_src("(binding [*x* 1] (set! *x* 2) *x*)", &mut env).unwrap();
        assert_eq!(inside, Value::Long(2));
        // root still 10
        let root = eval_src("*x*", &mut env).unwrap();
        assert_eq!(root, Value::Long(10));
    }

    #[test]
    fn test_with_bindings_star() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 10)", &mut env).unwrap();
        let result = eval_src("(with-bindings* {#'*x* 99} (fn [] *x*))", &mut env).unwrap();
        assert_eq!(result, Value::Long(99));
    }

    #[test]
    fn test_binding_fully_qualified_cross_ns_dynamic_var() {
        let (_, mut env) = make_env();
        let result = eval_src(
            r#"
            (ns other.ns)
            (def ^:dynamic *dispatch* nil)
            (ns user)
            (binding [other.ns/*dispatch* (fn [x] x)]
              (other.ns/*dispatch* 42))
            "#,
            &mut env,
        )
        .unwrap();
        assert_eq!(result, Value::Long(42));
    }

    #[test]
    fn test_binding_aliased_cross_ns_dynamic_var() {
        // (binding [alias/*var* v] ...) must resolve `alias` through the
        // current ns's `:require :as` aliases, exactly like ordinary
        // qualified-symbol lookup — this is how Replicant's public
        // `set-dispatch!`/life-cycle dispatch binds `*dispatch*` across
        // namespaces.
        let dir = temp_ns_dir("binding_aliased_cross_ns_dynamic_var");
        std::fs::create_dir_all(dir.join("replicant")).unwrap();
        std::fs::write(
            dir.join("replicant").join("core.cljrs"),
            r#"(ns replicant.core)
               (def ^:dynamic *dispatch* nil)
               (defn call-dispatch [x] (*dispatch* x))"#,
        )
        .unwrap();
        let (_, mut env) = make_env_with_paths(vec![dir]);
        let result = eval_src(
            r#"
            (ns life-cycle-test
              (:require [replicant.core :as r]))
            (binding [r/*dispatch* (fn [x] x)]
              (r/call-dispatch 42))
            "#,
            &mut env,
        )
        .unwrap();
        assert_eq!(result, Value::Long(42));
    }

    #[test]
    fn test_meta_on_var() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 1)", &mut env).unwrap();
        let m = eval_src("(meta #'*x*)", &mut env).unwrap();
        // meta should be {:dynamic true}
        if let Value::Map(mv) = &m {
            let kw = Value::keyword(cljrs_value::Keyword::parse("dynamic"));
            assert_eq!(mv.get(&kw), Some(Value::Bool(true)));
        } else {
            panic!("expected map, got {m:?}");
        }
    }

    #[test]
    fn test_bound_pred() {
        let (_, mut env) = make_env();
        eval_src("(def ^:dynamic *x* 1)", &mut env).unwrap();
        let t = eval_src("(bound? #'*x*)", &mut env).unwrap();
        assert_eq!(t, Value::Bool(true));
    }

    #[test]
    fn test_alter_var_root() {
        let (_, mut env) = make_env();
        eval_src("(def x 1)", &mut env).unwrap();
        eval_src("(alter-var-root #'x inc)", &mut env).unwrap();
        let val = eval_src("x", &mut env).unwrap();
        assert_eq!(val, Value::Long(2));
    }

    // ── clojure.test ─────────────────────────────────────────────────────────

    #[test]
    fn test_clojure_test_is_pass() {
        // (is expr) returns true on a passing assertion.
        let (_, mut env) = make_env();
        eval_src(
            "(require '[clojure.test :refer [is deftest run-tests]])",
            &mut env,
        )
        .unwrap();
        let v = eval_src("(is (= 1 1))", &mut env).unwrap();
        assert_eq!(v, Value::Bool(true));
    }

    #[test]
    fn test_clojure_test_is_fail() {
        // (is expr) returns false on a failing assertion.
        let (_, mut env) = make_env();
        eval_src("(require '[clojure.test :refer [is]])", &mut env).unwrap();
        let v = eval_src("(is (= 1 2))", &mut env).unwrap();
        assert_eq!(v, Value::Bool(false));
    }

    #[test]
    fn test_clojure_test_is_catch_error() {
        // (is expr) catches runtime errors and returns false.
        let (_, mut env) = make_env();
        eval_src("(require '[clojure.test :refer [is]])", &mut env).unwrap();
        let v = eval_src("(is (/ 1 0))", &mut env).unwrap();
        assert_eq!(v, Value::Bool(false));
    }

    #[test]
    fn test_clojure_test_deftest_and_run() {
        // deftest + run-tests smoke test: counters reflect pass/fail.
        let (_, mut env) = make_env();
        eval_src(
            "(require '[clojure.test :refer [deftest is run-tests]])",
            &mut env,
        )
        .unwrap();
        eval_src("(deftest my-passing-test (is (= 1 1)))", &mut env).unwrap();
        eval_src("(deftest my-failing-test (is (= 1 2)))", &mut env).unwrap();
        let counters = eval_src("(run-tests)", &mut env).unwrap();
        // Should have run 2 tests, 1 pass, 1 fail.
        if let Value::Map(m) = counters {
            let get = |k: &str| {
                m.get(&Value::keyword(cljrs_value::Keyword {
                    namespace: None,
                    name: Arc::from(k),
                }))
            };
            assert_eq!(get("test"), Some(Value::Long(2)));
            assert_eq!(get("pass"), Some(Value::Long(1)));
            assert_eq!(get("fail"), Some(Value::Long(1)));
            assert_eq!(get("error"), Some(Value::Long(0)));
        } else {
            panic!("expected map from run-tests, got {counters:?}");
        }
    }

    #[test]
    fn test_alter_meta_bang() {
        // alter-meta! applies fn to var's meta and stores result.
        let (_, mut env) = make_env();
        eval_src("(def myvar 42)", &mut env).unwrap();
        eval_src("(alter-meta! #'myvar assoc :foo :bar)", &mut env).unwrap();
        let m = eval_src("(meta #'myvar)", &mut env).unwrap();
        if let Value::Map(map) = m {
            let foo_key = Value::keyword(cljrs_value::Keyword {
                namespace: None,
                name: Arc::from("foo"),
            });
            assert!(map.get(&foo_key).is_some());
        } else {
            panic!("expected map, got {m:?}");
        }
    }

    #[test]
    fn test_catch_runtime_error() {
        // (try (/ 1 0) (catch Exception e "caught")) => "caught"
        let (_, mut env) = make_env();
        let v = eval_src(r#"(try (/ 1 0) (catch Exception e "caught"))"#, &mut env).unwrap();
        assert_eq!(v, Value::string("caught".to_string()));
    }

    #[test]
    fn test_ns_resolve() {
        let (_, mut env) = make_env();
        eval_src("(def somevar 99)", &mut env).unwrap();
        // ns-resolve with current ns returns the var.
        let v = eval_src("(ns-resolve *ns* 'somevar)", &mut env).unwrap();
        assert!(matches!(v, Value::Var(_)));
        // ns-resolve for non-existent symbol returns nil.
        let v2 = eval_src("(ns-resolve *ns* 'nonexistent)", &mut env).unwrap();
        assert_eq!(v2, Value::Nil);
    }

    // ── Persistent structure virtualization ──────────────────────────────

    #[test]
    fn test_assoc_chain_virtualized() {
        // Assoc chain where intermediates aren't used — should be virtualized.
        let v = eval_str(
            "(let [m {}
                   a (assoc m :x 1)
                   b (assoc a :y 2)
                   c (assoc b :z 3)]
               c)",
        )
        .unwrap();
        // Result should be {:x 1, :y 2, :z 3}.
        assert!(matches!(&v, Value::Map(_)));
        if let Value::Map(m) = &v {
            assert_eq!(m.count(), 3);
            assert_eq!(m.get(&Value::keyword(Keyword::simple("x"))), Some(long(1)));
            assert_eq!(m.get(&Value::keyword(Keyword::simple("y"))), Some(long(2)));
            assert_eq!(m.get(&Value::keyword(Keyword::simple("z"))), Some(long(3)));
        }
    }

    #[test]
    fn test_conj_chain_virtualized() {
        // Conj chain on a vector.
        let v = eval_str(
            "(let [v [1]
                   a (conj v 2)
                   b (conj a 3)
                   c (conj b 4)]
               c)",
        )
        .unwrap();
        assert_eq!(v, eval_str("[1 2 3 4]").unwrap());
    }

    #[test]
    fn test_assoc_chain_intermediate_used_no_virtualize() {
        // If an intermediate is used in the body, virtualization should not apply,
        // but the result should still be correct.
        let v = eval_str(
            "(let [a (assoc {} :x 1)
                   b (assoc a :y 2)]
               (list (count a) (count b)))",
        )
        .unwrap();
        // a has 1 entry, b has 2.
        if let Value::List(l) = &v {
            let items: Vec<_> = l.get().iter().cloned().collect();
            assert_eq!(items, vec![long(1), long(2)]);
        } else {
            panic!("expected list, got {:?}", v);
        }
    }

    #[test]
    fn test_assoc_chain_on_existing_map() {
        // Chain on an existing non-empty map.
        let v = eval_str(
            "(let [m {:a 1}
                   a (assoc m :b 2)
                   b (assoc a :c 3)]
               b)",
        )
        .unwrap();
        if let Value::Map(m) = &v {
            assert_eq!(m.count(), 3);
        } else {
            panic!("expected map");
        }
    }

    // ── :pre/:post conditions ─────────────────────────────────────────────

    #[test]
    fn test_post_condition_percent_bound() {
        // % must resolve to the return value inside :post conditions.
        let v = eval_str("(defn g [x] {:post [(pos? %)]} (inc x)) (g 5)").unwrap();
        assert_eq!(v, long(6));
    }

    #[test]
    fn test_post_condition_violation_throws() {
        // A failing :post condition must throw.
        let r = eval_str("(defn g [x] {:post [(neg? %)]} (inc x)) (g 5)");
        assert!(r.is_err(), "expected error from failing :post condition");
    }

    #[test]
    fn test_pre_condition_passes() {
        let v = eval_str("(defn g [x] {:pre [(pos? x)]} (inc x)) (g 5)").unwrap();
        assert_eq!(v, long(6));
    }

    #[test]
    fn test_pre_condition_violation_throws() {
        let r = eval_str("(defn g [x] {:pre [(pos? x)]} (inc x)) (g -1)");
        assert!(r.is_err(), "expected error from failing :pre condition");
    }

    #[test]
    fn test_pre_and_post_conditions() {
        let v = eval_str("(defn g [x] {:pre [(pos? x)] :post [(> % x)]} (inc x)) (g 3)").unwrap();
        assert_eq!(v, long(4));
    }

    #[test]
    fn test_post_condition_no_pre() {
        // :post only (no :pre).
        let v = eval_str("(defn h [x] {:post [(number? %)]} (inc x)) (h 2)").unwrap();
        assert_eq!(v, long(3));
    }

    #[test]
    fn test_pre_condition_no_post() {
        // :pre only (no :post); existing test variant without conditions map.
        let v = eval_str("(defn h [x] {:pre [(number? x)]} x) (h 42)").unwrap();
        assert_eq!(v, long(42));
    }
}