fix(tvix/eval): fix b/281 by adding Value::Catchable

This commit makes catchable errors a variant of Value.

The main downside of this approach is that we lose the ability to
use Rust's `?` syntax for propagating catchable errors.

Change-Id: Ibe89438d8a70dcec29e016df692b5bf88a5cad13
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9289
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: Adam Joseph <adam@westernsemico.com>
Tested-by: BuildkiteCI
This commit is contained in:
Adam Joseph 2023-09-09 22:02:56 -07:00 committed by clbot
parent 926459ce69
commit 05f42519b5
16 changed files with 320 additions and 247 deletions

View file

@ -6,7 +6,9 @@ use std::collections::{btree_map, BTreeSet};
use std::rc::Rc; use std::rc::Rc;
use tvix_eval::builtin_macros::builtins; use tvix_eval::builtin_macros::builtins;
use tvix_eval::generators::{self, emit_warning_kind, GenCo}; use tvix_eval::generators::{self, emit_warning_kind, GenCo};
use tvix_eval::{AddContext, CoercionKind, ErrorKind, NixAttrs, NixList, Value, WarningKind}; use tvix_eval::{
AddContext, CatchableErrorKind, CoercionKind, ErrorKind, NixAttrs, NixList, Value, WarningKind,
};
use crate::errors::Error; use crate::errors::Error;
use crate::known_paths::{KnownPaths, PathKind, PathName}; use crate::known_paths::{KnownPaths, PathKind, PathName};
@ -150,19 +152,22 @@ async fn handle_derivation_parameters(
name: &str, name: &str,
value: &Value, value: &Value,
val_str: &str, val_str: &str,
) -> Result<bool, ErrorKind> { ) -> Result<Result<bool, CatchableErrorKind>, ErrorKind> {
match name { match name {
IGNORE_NULLS => return Ok(false), IGNORE_NULLS => return Ok(Ok(false)),
// Command line arguments to the builder. // Command line arguments to the builder.
"args" => { "args" => {
let args = value.to_list()?; let args = value.to_list()?;
for arg in args { for arg in args {
drv.arguments.push(strong_coerce_to_string(co, arg).await?); match strong_coerce_to_string(co, arg).await? {
Err(cek) => return Ok(Err(cek)),
Ok(s) => drv.arguments.push(s),
}
} }
// The arguments do not appear in the environment. // The arguments do not appear in the environment.
return Ok(false); return Ok(Ok(false));
} }
// Explicitly specified drv outputs (instead of default [ "out" ]) // Explicitly specified drv outputs (instead of default [ "out" ])
@ -185,14 +190,18 @@ async fn handle_derivation_parameters(
_ => {} _ => {}
} }
Ok(true) Ok(Ok(true))
} }
async fn strong_coerce_to_string(co: &GenCo, val: Value) -> Result<String, ErrorKind> { async fn strong_coerce_to_string(
co: &GenCo,
val: Value,
) -> Result<Result<String, CatchableErrorKind>, ErrorKind> {
let val = generators::request_force(co, val).await; let val = generators::request_force(co, val).await;
let val_str = generators::request_string_coerce(co, val, CoercionKind::Strong).await; match generators::request_string_coerce(co, val, CoercionKind::Strong).await {
Err(cek) => Ok(Err(cek)),
Ok(val_str.as_str().to_string()) Ok(val_str) => Ok(Ok(val_str.as_str().to_string())),
}
} }
#[builtins(state = "Rc<RefCell<KnownPaths>>")] #[builtins(state = "Rc<RefCell<KnownPaths>>")]
@ -256,12 +265,15 @@ mod derivation_builtins {
co: &GenCo, co: &GenCo,
attrs: &NixAttrs, attrs: &NixAttrs,
key: &str, key: &str,
) -> Result<Option<String>, ErrorKind> { ) -> Result<Result<Option<String>, CatchableErrorKind>, ErrorKind> {
if let Some(attr) = attrs.select(key) { if let Some(attr) = attrs.select(key) {
return Ok(Some(strong_coerce_to_string(co, attr.clone()).await?)); match strong_coerce_to_string(co, attr.clone()).await? {
Err(cek) => return Ok(Err(cek)),
Ok(str) => return Ok(Ok(Some(str))),
}
} }
Ok(None) Ok(Ok(None))
} }
for (name, value) in input.clone().into_iter_sorted() { for (name, value) in input.clone().into_iter_sorted() {
@ -270,38 +282,60 @@ mod derivation_builtins {
continue; continue;
} }
let val_str = strong_coerce_to_string(&co, value.clone()).await?; match strong_coerce_to_string(&co, value.clone()).await? {
Err(cek) => return Ok(Value::Catchable(cek)),
Ok(val_str) => {
// handle_derivation_parameters tells us whether the
// argument should be added to the environment; continue
// to the next one otherwise
match handle_derivation_parameters(
&mut drv,
&co,
name.as_str(),
&value,
&val_str,
)
.await?
{
Err(cek) => return Ok(Value::Catchable(cek)),
Ok(false) => continue,
_ => (),
}
// handle_derivation_parameters tells us whether the // Most of these are also added to the builder's environment in "raw" form.
// argument should be added to the environment; continue if drv
// to the next one otherwise .environment
if !handle_derivation_parameters(&mut drv, &co, name.as_str(), &value, &val_str).await? .insert(name.as_str().to_string(), val_str.into())
{ .is_some()
continue; {
} return Err(Error::DuplicateEnvVar(name.as_str().to_string()).into());
}
// Most of these are also added to the builder's environment in "raw" form. }
if drv
.environment
.insert(name.as_str().to_string(), val_str.into())
.is_some()
{
return Err(Error::DuplicateEnvVar(name.as_str().to_string()).into());
} }
} }
populate_output_configuration( let output_hash = match select_string(&co, &input, "outputHash")
&mut drv, .await
select_string(&co, &input, "outputHash") .context("evaluating the `outputHash` parameter")?
.await {
.context("evaluating the `outputHash` parameter")?, Err(cek) => return Ok(Value::Catchable(cek)),
select_string(&co, &input, "outputHashAlgo") Ok(s) => s,
.await };
.context("evaluating the `outputHashAlgo` parameter")?, let output_hash_algo = match select_string(&co, &input, "outputHashAlgo")
select_string(&co, &input, "outputHashMode") .await
.await .context("evaluating the `outputHashAlgo` parameter")?
.context("evaluating the `outputHashMode` parameter")?, {
)?; Err(cek) => return Ok(Value::Catchable(cek)),
Ok(s) => s,
};
let output_hash_mode = match select_string(&co, &input, "outputHashMode")
.await
.context("evaluating the `outputHashMode` parameter")?
{
Err(cek) => return Ok(Value::Catchable(cek)),
Ok(s) => s,
};
populate_output_configuration(&mut drv, output_hash, output_hash_algo, output_hash_mode)?;
// Scan references in relevant attributes to detect any build-references. // Scan references in relevant attributes to detect any build-references.
let references = { let references = {

View file

@ -27,40 +27,47 @@ mod impure_builtins {
#[builtin("pathExists")] #[builtin("pathExists")]
async fn builtin_path_exists(co: GenCo, path: Value) -> Result<Value, ErrorKind> { async fn builtin_path_exists(co: GenCo, path: Value) -> Result<Value, ErrorKind> {
let path = coerce_value_to_path(&co, path).await?; match coerce_value_to_path(&co, path).await? {
Ok(generators::request_path_exists(&co, path).await) Err(cek) => Ok(Value::Catchable(cek)),
Ok(path) => Ok(generators::request_path_exists(&co, path).await),
}
} }
#[builtin("readDir")] #[builtin("readDir")]
async fn builtin_read_dir(co: GenCo, path: Value) -> Result<Value, ErrorKind> { async fn builtin_read_dir(co: GenCo, path: Value) -> Result<Value, ErrorKind> {
let path = coerce_value_to_path(&co, path).await?; match coerce_value_to_path(&co, path).await? {
Err(cek) => Ok(Value::Catchable(cek)),
Ok(path) => {
let dir = generators::request_read_dir(&co, path).await;
let res = dir.into_iter().map(|(name, ftype)| {
(
// TODO: propagate Vec<u8> or bytes::Bytes into NixString.
NixString::from(
String::from_utf8(name.to_vec()).expect("parsing file name as string"),
),
Value::String(
match ftype {
FileType::Directory => "directory",
FileType::Regular => "regular",
FileType::Symlink => "symlink",
FileType::Unknown => "unknown",
}
.into(),
),
)
});
let dir = generators::request_read_dir(&co, path).await; Ok(Value::attrs(NixAttrs::from_iter(res)))
let res = dir.into_iter().map(|(name, ftype)| { }
( }
// TODO: propagate Vec<u8> or bytes::Bytes into NixString.
NixString::from(
String::from_utf8(name.to_vec()).expect("parsing file name as string"),
),
Value::String(
match ftype {
FileType::Directory => "directory",
FileType::Regular => "regular",
FileType::Symlink => "symlink",
FileType::Unknown => "unknown",
}
.into(),
),
)
});
Ok(Value::attrs(NixAttrs::from_iter(res)))
} }
#[builtin("readFile")] #[builtin("readFile")]
async fn builtin_read_file(co: GenCo, path: Value) -> Result<Value, ErrorKind> { async fn builtin_read_file(co: GenCo, path: Value) -> Result<Value, ErrorKind> {
let path = coerce_value_to_path(&co, path).await?; match coerce_value_to_path(&co, path).await? {
Ok(generators::request_read_to_string(&co, path).await) Err(cek) => Ok(Value::Catchable(cek)),
Ok(path) => Ok(generators::request_read_to_string(&co, path).await),
}
} }
} }

View file

@ -40,18 +40,25 @@ pub const CURRENT_PLATFORM: &str = env!("TVIX_CURRENT_SYSTEM");
/// builtin. This coercion can _never_ be performed in a Nix program /// builtin. This coercion can _never_ be performed in a Nix program
/// without using builtins (i.e. the trick `path: /. + path` to /// without using builtins (i.e. the trick `path: /. + path` to
/// convert from a string to a path wouldn't hit this code). /// convert from a string to a path wouldn't hit this code).
pub async fn coerce_value_to_path(co: &GenCo, v: Value) -> Result<PathBuf, ErrorKind> { pub async fn coerce_value_to_path(
co: &GenCo,
v: Value,
) -> Result<Result<PathBuf, CatchableErrorKind>, ErrorKind> {
let value = generators::request_force(co, v).await; let value = generators::request_force(co, v).await;
if let Value::Path(p) = value { if let Value::Path(p) = value {
return Ok(*p); return Ok(Ok(*p));
} }
let vs = generators::request_string_coerce(co, value, CoercionKind::Weak).await; match generators::request_string_coerce(co, value, CoercionKind::Weak).await {
let path = PathBuf::from(vs.as_str()); Ok(vs) => {
if path.is_absolute() { let path = PathBuf::from(vs.as_str());
Ok(path) if path.is_absolute() {
} else { Ok(Ok(path))
Err(ErrorKind::NotAnAbsolutePath(path)) } else {
Err(ErrorKind::NotAnAbsolutePath(path))
}
}
Err(cek) => Ok(Err(cek)),
} }
} }
@ -218,8 +225,10 @@ mod pure_builtins {
if i != 0 { if i != 0 {
res.push_str(&separator); res.push_str(&separator);
} }
let s = generators::request_string_coerce(&co, val, CoercionKind::Weak).await; match generators::request_string_coerce(&co, val, CoercionKind::Weak).await {
res.push_str(s.as_str()); Ok(s) => res.push_str(s.as_str()),
Err(c) => return Ok(Value::Catchable(c)),
}
} }
Ok(res.into()) Ok(res.into())
} }
@ -313,6 +322,9 @@ mod pure_builtins {
// and our tests for foldl'. // and our tests for foldl'.
nul = generators::request_call_with(&co, op.clone(), [nul, val]).await; nul = generators::request_call_with(&co, op.clone(), [nul, val]).await;
nul = generators::request_force(&co, nul).await; nul = generators::request_force(&co, nul).await;
if let c @ Value::Catchable(_) = nul {
return Ok(c);
}
} }
Ok(nul) Ok(nul)
@ -340,9 +352,13 @@ mod pure_builtins {
#[builtin("toJSON")] #[builtin("toJSON")]
async fn builtin_to_json(co: GenCo, val: Value) -> Result<Value, ErrorKind> { async fn builtin_to_json(co: GenCo, val: Value) -> Result<Value, ErrorKind> {
let json_value = val.to_json(&co).await?; match val.to_json(&co).await? {
let json_str = serde_json::to_string(&json_value)?; Err(cek) => Ok(Value::Catchable(cek)),
Ok(json_str.into()) Ok(json_value) => {
let json_str = serde_json::to_string(&json_value)?;
Ok(json_str.into())
}
}
} }
#[builtin("fromTOML")] #[builtin("fromTOML")]
@ -893,7 +909,7 @@ mod pure_builtins {
#[builtin("throw")] #[builtin("throw")]
async fn builtin_throw(co: GenCo, message: Value) -> Result<Value, ErrorKind> { async fn builtin_throw(co: GenCo, message: Value) -> Result<Value, ErrorKind> {
Err(ErrorKind::CatchableErrorKind(CatchableErrorKind::Throw( Ok(Value::Catchable(CatchableErrorKind::Throw(
message.to_str()?.to_string(), message.to_str()?.to_string(),
))) )))
} }
@ -929,15 +945,20 @@ mod pure_builtins {
#[builtin("toPath")] #[builtin("toPath")]
async fn builtin_to_path(co: GenCo, s: Value) -> Result<Value, ErrorKind> { async fn builtin_to_path(co: GenCo, s: Value) -> Result<Value, ErrorKind> {
let path: Value = crate::value::canon_path(coerce_value_to_path(&co, s).await?).into(); match coerce_value_to_path(&co, s).await? {
Ok(path.coerce_to_string(co, CoercionKind::Weak).await?) Err(cek) => return Ok(Value::Catchable(cek)),
Ok(path) => {
let path: Value = crate::value::canon_path(path).into();
Ok(path.coerce_to_string(co, CoercionKind::Weak).await?)
}
}
} }
#[builtin("tryEval")] #[builtin("tryEval")]
async fn builtin_try_eval(co: GenCo, #[lazy] e: Value) -> Result<Value, ErrorKind> { async fn builtin_try_eval(co: GenCo, #[lazy] e: Value) -> Result<Value, ErrorKind> {
let res = match generators::request_try_force(&co, e).await { let res = match generators::request_try_force(&co, e).await {
Some(value) => [("value", value), ("success", true.into())], Value::Catchable(_) => [("value", false.into()), ("success", false.into())],
None => [("value", false.into()), ("success", false.into())], value => [("value", value), ("success", true.into())],
}; };
Ok(Value::attrs(NixAttrs::from_iter(res.into_iter()))) Ok(Value::attrs(NixAttrs::from_iter(res.into_iter())))

View file

@ -134,6 +134,10 @@ fn value_variant_to_xml<W: Write>(w: &mut EventWriter<W>, value: &Value) -> Resu
metadata: Some(Rc::new(value.clone())), metadata: Some(Rc::new(value.clone())),
}) })
} }
Value::Catchable(_) => {
panic!("tvix bug: value_to_xml() called on a value which had not been deep-forced")
}
}?; }?;
Ok(()) Ok(())

View file

@ -25,7 +25,10 @@ async fn import_impl(
mut args: Vec<Value>, mut args: Vec<Value>,
) -> Result<Value, ErrorKind> { ) -> Result<Value, ErrorKind> {
// TODO(sterni): canon_path()? // TODO(sterni): canon_path()?
let mut path = coerce_value_to_path(&co, args.pop().unwrap()).await?; let mut path = match coerce_value_to_path(&co, args.pop().unwrap()).await? {
Err(cek) => return Ok(Value::Catchable(cek)),
Ok(path) => path,
};
if path.is_dir() { if path.is_dir() {
path.push("default.nix"); path.push("default.nix");
@ -36,11 +39,8 @@ async fn import_impl(
} }
// TODO(tazjin): make this return a string directly instead // TODO(tazjin): make this return a string directly instead
let contents = generators::request_read_to_string(&co, path.clone()) let contents: Value = generators::request_read_to_string(&co, path.clone()).await;
.await let contents = contents.to_str()?.as_str().to_string();
.to_str()?
.as_str()
.to_string();
let parsed = rnix::ast::Root::parse(&contents); let parsed = rnix::ast::Root::parse(&contents);
let errors = parsed.errors(); let errors = parsed.errors();

View file

@ -396,11 +396,11 @@ impl Compiler<'_> {
} else if raw_path.starts_with('<') { } else if raw_path.starts_with('<') {
// TODO: decide what to do with findFile // TODO: decide what to do with findFile
if raw_path.len() == 2 { if raw_path.len() == 2 {
return self.emit_error( return self.emit_constant(
node, Value::Catchable(CatchableErrorKind::NixPathResolution(
ErrorKind::CatchableErrorKind(CatchableErrorKind::NixPathResolution(
"Empty <> path not allowed".into(), "Empty <> path not allowed".into(),
)), )),
node,
); );
} }
let path = &raw_path[1..(raw_path.len() - 1)]; let path = &raw_path[1..(raw_path.len() - 1)];

View file

@ -16,7 +16,28 @@ use crate::spans::ToSpan;
use crate::value::{CoercionKind, NixString}; use crate::value::{CoercionKind, NixString};
use crate::{SourceCode, Value}; use crate::{SourceCode, Value};
/// "CatchableErrorKind" errors -- those which can be detected by `builtins.tryEval`. /// "CatchableErrorKind" errors -- those which can be detected by
/// `builtins.tryEval`.
///
/// Note: this type is deliberately *not* incorporated as a variant
/// of ErrorKind, because then Result<Value,ErrorKind> would have
/// redundant representations for catchable errors, which would make
/// it too easy to handle errors incorrectly:
///
/// - Ok(Value::Catchable(cek))
/// - Err(ErrorKind::ThisVariantDoesNotExist(cek))
///
/// Because CatchableErrorKind is not a variant of ErrorKind, you
/// will often see functions which return a type like:
///
/// Result<Result<T,CatchableErrorKind>,ErrorKind>
///
/// ... where T is any type other than Value. This is unfortunate,
/// because Rust's magic `?`-syntax does not work on nested Result
/// values like this.
///
/// TODO(amjoseph): investigate result<T,Either<CatchableErrorKind,ErrorKind>>
///
#[derive(Clone, Debug)] #[derive(Clone, Debug)]
pub enum CatchableErrorKind { pub enum CatchableErrorKind {
Throw(String), Throw(String),
@ -180,14 +201,6 @@ pub enum ErrorKind {
context: String, context: String,
underlying: Box<ErrorKind>, underlying: Box<ErrorKind>,
}, },
CatchableErrorKind(CatchableErrorKind),
}
impl From<CatchableErrorKind> for ErrorKind {
fn from(c: CatchableErrorKind) -> ErrorKind {
ErrorKind::CatchableErrorKind(c)
}
} }
impl error::Error for Error { impl error::Error for Error {
@ -243,17 +256,6 @@ impl From<io::Error> for ErrorKind {
} }
} }
impl ErrorKind {
/// Returns `true` if this error can be caught by `builtins.tryEval`
pub fn is_catchable(&self) -> bool {
match self {
Self::CatchableErrorKind(_) => true,
Self::NativeError { err, .. } | Self::BytecodeError(err) => err.kind.is_catchable(),
_ => false,
}
}
}
impl From<serde_json::Error> for ErrorKind { impl From<serde_json::Error> for ErrorKind {
fn from(err: serde_json::Error) -> Self { fn from(err: serde_json::Error) -> Self {
// Can't just put the `serde_json::Error` in the ErrorKind since it doesn't impl `Clone` // Can't just put the `serde_json::Error` in the ErrorKind since it doesn't impl `Clone`
@ -297,13 +299,7 @@ impl Error {
impl Display for ErrorKind { impl Display for ErrorKind {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match &self { match &self {
ErrorKind::CatchableErrorKind(CatchableErrorKind::Throw(msg)) => {
write!(f, "error thrown: {}", msg)
}
ErrorKind::Abort(msg) => write!(f, "evaluation aborted: {}", msg), ErrorKind::Abort(msg) => write!(f, "evaluation aborted: {}", msg),
ErrorKind::CatchableErrorKind(CatchableErrorKind::AssertionFailed) => {
write!(f, "assertion failed")
}
ErrorKind::DivisionByZero => write!(f, "division by zero"), ErrorKind::DivisionByZero => write!(f, "division by zero"),
@ -340,8 +336,7 @@ impl Display for ErrorKind {
write!(f, "can not compare a {} with a {}", lhs, rhs) write!(f, "can not compare a {} with a {}", lhs, rhs)
} }
ErrorKind::CatchableErrorKind(CatchableErrorKind::NixPathResolution(err)) ErrorKind::RelativePathResolution(err) => {
| ErrorKind::RelativePathResolution(err) => {
write!(f, "could not resolve path: {}", err) write!(f, "could not resolve path: {}", err)
} }
@ -741,15 +736,12 @@ impl Error {
let label = match &self.kind { let label = match &self.kind {
ErrorKind::DuplicateAttrsKey { .. } => "in this attribute set", ErrorKind::DuplicateAttrsKey { .. } => "in this attribute set",
ErrorKind::InvalidAttributeName(_) => "in this attribute set", ErrorKind::InvalidAttributeName(_) => "in this attribute set",
ErrorKind::CatchableErrorKind(CatchableErrorKind::NixPathResolution(_)) ErrorKind::RelativePathResolution(_) => "in this path literal",
| ErrorKind::RelativePathResolution(_) => "in this path literal",
ErrorKind::UnexpectedArgument { .. } => "in this function call", ErrorKind::UnexpectedArgument { .. } => "in this function call",
// The spans for some errors don't have any more descriptive stuff // The spans for some errors don't have any more descriptive stuff
// in them, or we don't utilise it yet. // in them, or we don't utilise it yet.
ErrorKind::CatchableErrorKind(CatchableErrorKind::Throw(_)) ErrorKind::Abort(_)
| ErrorKind::Abort(_)
| ErrorKind::CatchableErrorKind(CatchableErrorKind::AssertionFailed)
| ErrorKind::AttributeNotFound { .. } | ErrorKind::AttributeNotFound { .. }
| ErrorKind::IndexOutOfBounds { .. } | ErrorKind::IndexOutOfBounds { .. }
| ErrorKind::TailEmptyList | ErrorKind::TailEmptyList
@ -790,14 +782,11 @@ impl Error {
/// used to refer users to documentation. /// used to refer users to documentation.
fn code(&self) -> &'static str { fn code(&self) -> &'static str {
match self.kind { match self.kind {
ErrorKind::CatchableErrorKind(CatchableErrorKind::Throw(_)) => "E001",
ErrorKind::Abort(_) => "E002", ErrorKind::Abort(_) => "E002",
ErrorKind::CatchableErrorKind(CatchableErrorKind::AssertionFailed) => "E003",
ErrorKind::InvalidAttributeName { .. } => "E004", ErrorKind::InvalidAttributeName { .. } => "E004",
ErrorKind::AttributeNotFound { .. } => "E005", ErrorKind::AttributeNotFound { .. } => "E005",
ErrorKind::TypeError { .. } => "E006", ErrorKind::TypeError { .. } => "E006",
ErrorKind::Incomparable { .. } => "E007", ErrorKind::Incomparable { .. } => "E007",
ErrorKind::CatchableErrorKind(CatchableErrorKind::NixPathResolution(_)) => "E008",
ErrorKind::DynamicKeyInScope(_) => "E009", ErrorKind::DynamicKeyInScope(_) => "E009",
ErrorKind::UnknownStaticVariable => "E010", ErrorKind::UnknownStaticVariable => "E010",
ErrorKind::UnknownDynamicVariable(_) => "E011", ErrorKind::UnknownDynamicVariable(_) => "E011",

View file

@ -48,7 +48,7 @@ use crate::vm::run_lambda;
// Re-export the public interface used by other crates. // Re-export the public interface used by other crates.
pub use crate::compiler::{compile, prepare_globals, CompilationOutput}; pub use crate::compiler::{compile, prepare_globals, CompilationOutput};
pub use crate::errors::{AddContext, Error, ErrorKind, EvalResult}; pub use crate::errors::{AddContext, CatchableErrorKind, Error, ErrorKind, EvalResult};
pub use crate::io::{DummyIO, EvalIO, FileType}; pub use crate::io::{DummyIO, EvalIO, FileType};
pub use crate::pretty_ast::pretty_print_expr; pub use crate::pretty_ast::pretty_print_expr;
pub use crate::source::SourceCode; pub use crate::source::SourceCode;

View file

@ -124,22 +124,24 @@ pub struct NixSearchPath {
impl NixSearchPath { impl NixSearchPath {
/// Attempt to resolve the given `path` within this [`NixSearchPath`] using the /// Attempt to resolve the given `path` within this [`NixSearchPath`] using the
/// path resolution rules for `<...>`-style paths /// path resolution rules for `<...>`-style paths
pub fn resolve<P>(&self, io: &mut dyn EvalIO, path: P) -> Result<PathBuf, ErrorKind> pub fn resolve<P>(
&self,
io: &mut dyn EvalIO,
path: P,
) -> Result<Result<PathBuf, CatchableErrorKind>, ErrorKind>
where where
P: AsRef<Path>, P: AsRef<Path>,
{ {
let path = path.as_ref(); let path = path.as_ref();
for entry in &self.entries { for entry in &self.entries {
if let Some(p) = entry.resolve(io, path)? { if let Some(p) = entry.resolve(io, path)? {
return Ok(p); return Ok(Ok(p));
} }
} }
Err(ErrorKind::CatchableErrorKind( Ok(Err(CatchableErrorKind::NixPathResolution(format!(
CatchableErrorKind::NixPathResolution(format!( "path '{}' was not found in the Nix search path",
"path '{}' was not found in the Nix search path", path.display()
path.display() ))))
)),
))
} }
} }
@ -204,19 +206,19 @@ mod tests {
let nix_search_path = NixSearchPath::from_str("./.").unwrap(); let nix_search_path = NixSearchPath::from_str("./.").unwrap();
let mut io = StdIO {}; let mut io = StdIO {};
let res = nix_search_path.resolve(&mut io, "src").unwrap(); let res = nix_search_path.resolve(&mut io, "src").unwrap();
assert_eq!(res, current_dir().unwrap().join("src").clean()); assert_eq!(
res.unwrap().to_path_buf(),
current_dir().unwrap().join("src").clean()
);
} }
#[test] #[test]
fn failed_resolution() { fn failed_resolution() {
let nix_search_path = NixSearchPath::from_str("./.").unwrap(); let nix_search_path = NixSearchPath::from_str("./.").unwrap();
let mut io = StdIO {}; let mut io = StdIO {};
let err = nix_search_path.resolve(&mut io, "nope").unwrap_err(); let err = nix_search_path.resolve(&mut io, "nope").unwrap();
assert!( assert!(
matches!( matches!(err, Err(CatchableErrorKind::NixPathResolution(..))),
err,
ErrorKind::CatchableErrorKind(CatchableErrorKind::NixPathResolution(..))
),
"err = {err:?}" "err = {err:?}"
); );
} }
@ -226,7 +228,7 @@ mod tests {
let nix_search_path = NixSearchPath::from_str("./.:/").unwrap(); let nix_search_path = NixSearchPath::from_str("./.:/").unwrap();
let mut io = StdIO {}; let mut io = StdIO {};
let res = nix_search_path.resolve(&mut io, "etc").unwrap(); let res = nix_search_path.resolve(&mut io, "etc").unwrap();
assert_eq!(res, Path::new("/etc")); assert_eq!(res.unwrap().to_path_buf(), Path::new("/etc"));
} }
#[test] #[test]
@ -234,7 +236,10 @@ mod tests {
let nix_search_path = NixSearchPath::from_str("/:tvix=.").unwrap(); let nix_search_path = NixSearchPath::from_str("/:tvix=.").unwrap();
let mut io = StdIO {}; let mut io = StdIO {};
let res = nix_search_path.resolve(&mut io, "tvix/src").unwrap(); let res = nix_search_path.resolve(&mut io, "tvix/src").unwrap();
assert_eq!(res, current_dir().unwrap().join("src").clean()); assert_eq!(
res.unwrap().to_path_buf(),
current_dir().unwrap().join("src").clean()
);
} }
#[test] #[test]
@ -242,7 +247,7 @@ mod tests {
let nix_search_path = NixSearchPath::from_str("/:tvix=.").unwrap(); let nix_search_path = NixSearchPath::from_str("/:tvix=.").unwrap();
let mut io = StdIO {}; let mut io = StdIO {};
let res = nix_search_path.resolve(&mut io, "tvix").unwrap(); let res = nix_search_path.resolve(&mut io, "tvix").unwrap();
assert_eq!(res, current_dir().unwrap().clean()); assert_eq!(res.unwrap().to_path_buf(), current_dir().unwrap().clean());
} }
} }
} }

View file

@ -1,3 +1,4 @@
use crate::value::Value;
use builtin_macros::builtins; use builtin_macros::builtins;
use pretty_assertions::assert_eq; use pretty_assertions::assert_eq;
use test_generator::test_resources; use test_generator::test_resources;
@ -57,19 +58,23 @@ fn eval_test(code_path: &str, expect_success: bool) {
eval.builtins.extend(mock_builtins::builtins()); eval.builtins.extend(mock_builtins::builtins());
let result = eval.evaluate(); let result = eval.evaluate();
let failed = match result.value {
if expect_success && !result.errors.is_empty() { Some(Value::Catchable(_)) => true,
_ => !result.errors.is_empty(),
};
if expect_success && failed {
panic!( panic!(
"{code_path}: evaluation of eval-okay test should succeed, but failed with {:?}", "{code_path}: evaluation of eval-okay test should succeed, but failed with {:?}",
result.errors, result.errors,
); );
} }
if !expect_success && !result.errors.is_empty() { if !expect_success && failed {
return; return;
} }
let result_str = result.value.unwrap().to_string(); let value = result.value.unwrap();
let result_str = value.to_string();
if let Ok(exp) = std::fs::read_to_string(exp_path) { if let Ok(exp) = std::fs::read_to_string(exp_path) {
if expect_success { if expect_success {

View file

@ -393,7 +393,7 @@ impl NixAttrs {
// /another/ set with a __toString attr. // /another/ set with a __toString attr.
let s = generators::request_string_coerce(co, result, kind).await; let s = generators::request_string_coerce(co, result, kind).await;
return Some(s); return Some(s.ok()?);
} }
None None

View file

@ -4,15 +4,18 @@
/// as there is internal Nix logic that must happen within the /// as there is internal Nix logic that must happen within the
/// serialisation methods. /// serialisation methods.
use super::{CoercionKind, Value}; use super::{CoercionKind, Value};
use crate::errors::{CatchableErrorKind, ErrorKind};
use crate::generators::{self, GenCo}; use crate::generators::{self, GenCo};
use crate::ErrorKind;
use serde_json::value::to_value; use serde_json::value::to_value;
use serde_json::Value as Json; // name clash with *our* `Value` use serde_json::Value as Json; // name clash with *our* `Value`
use serde_json::{Map, Number}; use serde_json::{Map, Number};
impl Value { impl Value {
pub(crate) async fn to_json(self, co: &GenCo) -> Result<Json, ErrorKind> { pub(crate) async fn to_json(
self,
co: &GenCo,
) -> Result<Result<Json, CatchableErrorKind>, ErrorKind> {
let self_forced = generators::request_force(co, self).await; let self_forced = generators::request_force(co, self).await;
let value = match self_forced { let value = match self_forced {
@ -42,14 +45,14 @@ impl Value {
// serialise to the string-coerced version of the result of // serialise to the string-coerced version of the result of
// calling that. // calling that.
if let Some(s) = attrs.try_to_string(co, CoercionKind::Weak).await { if let Some(s) = attrs.try_to_string(co, CoercionKind::Weak).await {
return Ok(Json::String(s.as_str().to_string())); return Ok(Ok(Json::String(s.as_str().to_string())));
} }
// Attribute sets with an `outPath` attribute // Attribute sets with an `outPath` attribute
// serialise to a JSON serialisation of that inner // serialise to a JSON serialisation of that inner
// value (regardless of what it is!). // value (regardless of what it is!).
if let Some(out_path) = attrs.select("outPath") { if let Some(out_path) = attrs.select("outPath") {
return Ok(generators::request_to_json(co, out_path.clone()).await); return Ok(Ok(generators::request_to_json(co, out_path.clone()).await));
} }
let mut out = Map::with_capacity(attrs.len()); let mut out = Map::with_capacity(attrs.len());
@ -63,6 +66,8 @@ impl Value {
Json::Object(out) Json::Object(out)
} }
Value::Catchable(c) => return Ok(Err(c)),
val @ Value::Closure(_) val @ Value::Closure(_)
| val @ Value::Thunk(_) | val @ Value::Thunk(_)
| val @ Value::Builtin(_) | val @ Value::Builtin(_)
@ -76,12 +81,15 @@ impl Value {
} }
}; };
Ok(value) Ok(Ok(value))
} }
/// Generator version of the above, which wraps responses in /// Generator version of the above, which wraps responses in
/// Value::Json. /// Value::Json.
pub(crate) async fn to_json_generator(self, co: GenCo) -> Result<Value, ErrorKind> { pub(crate) async fn to_json_generator(self, co: GenCo) -> Result<Value, ErrorKind> {
Ok(Value::Json(self.to_json(&co).await?)) match self.to_json(&co).await? {
Err(cek) => Ok(Value::Catchable(cek)),
Ok(json) => Ok(Value::Json(json)),
}
} }
} }

View file

@ -20,7 +20,7 @@ mod path;
mod string; mod string;
mod thunk; mod thunk;
use crate::errors::ErrorKind; use crate::errors::{CatchableErrorKind, ErrorKind};
use crate::opcode::StackIdx; use crate::opcode::StackIdx;
use crate::spans::LightSpan; use crate::spans::LightSpan;
use crate::vm::generators::{self, GenCo}; use crate::vm::generators::{self, GenCo};
@ -81,6 +81,24 @@ pub enum Value {
#[serde(skip)] #[serde(skip)]
FinaliseRequest(bool), FinaliseRequest(bool),
#[serde(skip)]
Catchable(CatchableErrorKind),
}
impl From<CatchableErrorKind> for Value {
fn from(c: CatchableErrorKind) -> Value {
Value::Catchable(c)
}
}
impl<V> From<Result<V, CatchableErrorKind>> for Value
where
Value: From<V>,
{
fn from(v: Result<V, CatchableErrorKind>) -> Value {
v.map_or_else(|cek| Value::Catchable(cek), |v| v.into())
}
} }
lazy_static! { lazy_static! {
@ -222,18 +240,28 @@ impl Value {
Value::List(list) => { Value::List(list) => {
for val in list { for val in list {
generators::request_deep_force(&co, val.clone(), thunk_set.clone()).await; if let c @ Value::Catchable(_) =
generators::request_deep_force(&co, val.clone(), thunk_set.clone()).await
{
return Ok(c);
}
} }
} }
Value::Attrs(attrs) => { Value::Attrs(attrs) => {
for (_, val) in attrs.iter() { for (_, val) in attrs.iter() {
generators::request_deep_force(&co, val.clone(), thunk_set.clone()).await; if let c @ Value::Catchable(_) =
generators::request_deep_force(&co, val.clone(), thunk_set.clone()).await
{
return Ok(c);
}
} }
} }
Value::Thunk(_) => panic!("Tvix bug: force_value() returned a thunk"), Value::Thunk(_) => panic!("Tvix bug: force_value() returned a thunk"),
Value::Catchable(_) => return Ok(value),
Value::AttrNotFound Value::AttrNotFound
| Value::Blueprint(_) | Value::Blueprint(_)
| Value::DeferredUpvalue(_) | Value::DeferredUpvalue(_)
@ -279,8 +307,12 @@ impl Value {
} }
if let Some(out_path) = attrs.select("outPath") { if let Some(out_path) = attrs.select("outPath") {
let s = generators::request_string_coerce(&co, out_path.clone(), kind).await; return match generators::request_string_coerce(&co, out_path.clone(), kind)
return Ok(Value::String(s)); .await
{
Ok(s) => Ok(Value::String(s)),
Err(c) => Ok(Value::Catchable(c)),
};
} }
Err(ErrorKind::NotCoercibleToString { from: "set", kind }) Err(ErrorKind::NotCoercibleToString { from: "set", kind })
@ -308,8 +340,10 @@ impl Value {
out.push(' '); out.push(' ');
} }
let s = generators::request_string_coerce(&co, elem, kind).await; match generators::request_string_coerce(&co, elem, kind).await {
out.push_str(s.as_str()); Ok(s) => out.push_str(s.as_str()),
Err(c) => return Ok(Value::Catchable(c)),
}
} }
Ok(Value::String(out.into())) Ok(Value::String(out.into()))
@ -328,6 +362,8 @@ impl Value {
kind, kind,
}), }),
(c @ Value::Catchable(_), _) => return Ok(c),
(Value::AttrNotFound, _) (Value::AttrNotFound, _)
| (Value::Blueprint(_), _) | (Value::Blueprint(_), _)
| (Value::DeferredUpvalue(_), _) | (Value::DeferredUpvalue(_), _)
@ -384,6 +420,8 @@ impl Value {
let result = match (a, b) { let result = match (a, b) {
// Trivial comparisons // Trivial comparisons
(c @ Value::Catchable(_), _) => return Ok(c),
(_, c @ Value::Catchable(_)) => return Ok(c),
(Value::Null, Value::Null) => true, (Value::Null, Value::Null) => true,
(Value::Bool(b1), Value::Bool(b2)) => b1 == b2, (Value::Bool(b1), Value::Bool(b2)) => b1 == b2,
(Value::String(s1), Value::String(s2)) => s1 == s2, (Value::String(s1), Value::String(s2)) => s1 == s2,
@ -526,6 +564,7 @@ impl Value {
Value::UnresolvedPath(_) => "internal[unresolved_path]", Value::UnresolvedPath(_) => "internal[unresolved_path]",
Value::Json(_) => "internal[json]", Value::Json(_) => "internal[json]",
Value::FinaliseRequest(_) => "internal[finaliser_sentinel]", Value::FinaliseRequest(_) => "internal[finaliser_sentinel]",
Value::Catchable(_) => "internal[catchable]",
} }
} }
@ -533,6 +572,7 @@ impl Value {
gen_cast!(as_int, i64, "int", Value::Integer(x), *x); gen_cast!(as_int, i64, "int", Value::Integer(x), *x);
gen_cast!(as_float, f64, "float", Value::Float(x), *x); gen_cast!(as_float, f64, "float", Value::Float(x), *x);
gen_cast!(to_str, NixString, "string", Value::String(s), s.clone()); gen_cast!(to_str, NixString, "string", Value::String(s), s.clone());
gen_cast!(to_path, Box<PathBuf>, "path", Value::Path(p), p.clone());
gen_cast!(to_attrs, Box<NixAttrs>, "set", Value::Attrs(a), a.clone()); gen_cast!(to_attrs, Box<NixAttrs>, "set", Value::Attrs(a), a.clone());
gen_cast!(to_list, NixList, "list", Value::List(l), l.clone()); gen_cast!(to_list, NixList, "list", Value::List(l), l.clone());
gen_cast!( gen_cast!(
@ -660,6 +700,8 @@ impl Value {
// TODO: handle suspended thunks with a different explanation instead of panicking // TODO: handle suspended thunks with a different explanation instead of panicking
Value::Thunk(t) => t.value().explain(), Value::Thunk(t) => t.value().explain(),
Value::Catchable(_) => "a catchable failure".into(),
Value::AttrNotFound Value::AttrNotFound
| Value::Blueprint(_) | Value::Blueprint(_)
| Value::DeferredUpvalue(_) | Value::DeferredUpvalue(_)
@ -785,6 +827,7 @@ impl TotalDisplay for Value {
// Delegate thunk display to the type, as it must handle // Delegate thunk display to the type, as it must handle
// the case of already evaluated or cyclic thunks. // the case of already evaluated or cyclic thunks.
Value::Thunk(t) => t.total_fmt(f, set), Value::Thunk(t) => t.total_fmt(f, set),
Value::Catchable(_) => panic!("total_fmt() called on a CatchableErrorKind"),
} }
} }
} }

View file

@ -190,10 +190,6 @@ pub enum VMResponse {
/// VM response with a span to use at the current point. /// VM response with a span to use at the current point.
Span(LightSpan), Span(LightSpan),
/// Message returned by the VM when a catchable error is encountered during
/// the evaluation of `builtins.tryEval`.
ForceError,
} }
impl Display for VMResponse { impl Display for VMResponse {
@ -204,7 +200,6 @@ impl Display for VMResponse {
VMResponse::Path(p) => write!(f, "path({})", p.to_string_lossy()), VMResponse::Path(p) => write!(f, "path({})", p.to_string_lossy()),
VMResponse::Directory(d) => write!(f, "dir(len = {})", d.len()), VMResponse::Directory(d) => write!(f, "dir(len = {})", d.len()),
VMResponse::Span(_) => write!(f, "span"), VMResponse::Span(_) => write!(f, "span"),
VMResponse::ForceError => write!(f, "force_error"),
} }
} }
} }
@ -539,20 +534,18 @@ pub async fn request_force(co: &GenCo, val: Value) -> Value {
} }
} }
/// Force a value, but inform the caller (by returning `None`) if a catchable /// Force a value
/// error occured. pub(crate) async fn request_try_force(co: &GenCo, val: Value) -> Value {
pub(crate) async fn request_try_force(co: &GenCo, val: Value) -> Option<Value> {
if let Value::Thunk(_) = val { if let Value::Thunk(_) = val {
match co.yield_(VMRequest::TryForce(val)).await { match co.yield_(VMRequest::TryForce(val)).await {
VMResponse::Value(value) => Some(value), VMResponse::Value(value) => value,
VMResponse::ForceError => None,
msg => panic!( msg => panic!(
"Tvix bug: VM responded with incorrect generator message: {}", "Tvix bug: VM responded with incorrect generator message: {}",
msg msg
), ),
} }
} else { } else {
Some(val) val
} }
} }
@ -592,13 +585,18 @@ where
callable callable
} }
pub async fn request_string_coerce(co: &GenCo, val: Value, kind: CoercionKind) -> NixString { pub async fn request_string_coerce(
co: &GenCo,
val: Value,
kind: CoercionKind,
) -> Result<NixString, CatchableErrorKind> {
match val { match val {
Value::String(s) => s, Value::String(s) => Ok(s),
_ => match co.yield_(VMRequest::StringCoerce(val, kind)).await { _ => match co.yield_(VMRequest::StringCoerce(val, kind)).await {
VMResponse::Value(value) => value VMResponse::Value(Value::Catchable(c)) => Err(c),
VMResponse::Value(value) => Ok(value
.to_str() .to_str()
.expect("coerce_to_string always returns a string"), .expect("coerce_to_string always returns a string")),
msg => panic!( msg => panic!(
"Tvix bug: VM responded with incorrect generator message: {}", "Tvix bug: VM responded with incorrect generator message: {}",
msg msg

View file

@ -84,13 +84,6 @@ impl<T, S: GetSpan> WithSpan<T, S> for Result<T, ErrorKind> {
Err(kind) => { Err(kind) => {
let mut error = Error::new(kind, top_span.get_span()); let mut error = Error::new(kind, top_span.get_span());
// Short-circuit the wrapping if we're dealing with tryEval, in
// which case the error is hidden and does not need to be
// exhaustive.
if !vm.try_eval_frames.is_empty() && error.kind.is_catchable() {
return Err(error);
}
// Wrap the top-level error in chaining errors for each element // Wrap the top-level error in chaining errors for each element
// of the frame stack. // of the frame stack.
for frame in vm.frames.iter().rev() { for frame in vm.frames.iter().rev() {
@ -360,8 +353,6 @@ impl<'o> VM<'o> {
/// Run the VM's primary (outer) execution loop, continuing execution based /// Run the VM's primary (outer) execution loop, continuing execution based
/// on the current frame at the top of the frame stack. /// on the current frame at the top of the frame stack.
fn execute(mut self) -> EvalResult<RuntimeResult> { fn execute(mut self) -> EvalResult<RuntimeResult> {
let mut catchable_error_occurred = false;
while let Some(frame) = self.frames.pop() { while let Some(frame) = self.frames.pop() {
self.reasonable_span = frame.span(); self.reasonable_span = frame.span();
let frame_id = self.frames.len(); let frame_id = self.frames.len();
@ -377,21 +368,7 @@ impl<'o> VM<'o> {
.observer .observer
.observe_suspend_call_frame(frame_id, &self.stack), .observe_suspend_call_frame(frame_id, &self.stack),
Err(err) => { Err(err) => return Err(err),
if let Some(catching_frame_idx) = self.try_eval_frames.pop() {
if err.kind.is_catchable() {
self.observer.observe_exit_call_frame(frame_id, &self.stack);
catchable_error_occurred = true;
// truncate the frame stack back to the
// frame that can catch this error
self.frames.truncate(/* len = */ catching_frame_idx + 1);
continue;
}
}
return Err(err);
}
}; };
} }
@ -406,14 +383,7 @@ impl<'o> VM<'o> {
self.observer self.observer
.observe_enter_generator(frame_id, name, &self.stack); .observe_enter_generator(frame_id, name, &self.stack);
let initial_msg = if catchable_error_occurred { match self.run_generator(name, span, frame_id, state, generator, None) {
catchable_error_occurred = false;
Some(VMResponse::ForceError)
} else {
None
};
match self.run_generator(name, span, frame_id, state, generator, initial_msg) {
Ok(true) => { Ok(true) => {
self.observer self.observer
.observe_exit_generator(frame_id, name, &self.stack) .observe_exit_generator(frame_id, name, &self.stack)
@ -423,25 +393,7 @@ impl<'o> VM<'o> {
.observe_suspend_generator(frame_id, name, &self.stack) .observe_suspend_generator(frame_id, name, &self.stack)
} }
Err(err) => { Err(err) => return Err(err),
if let Some(catching_frame_idx) = self.try_eval_frames.pop() {
if err.kind.is_catchable() {
self.observer.observe_exit_generator(
frame_id,
name,
&self.stack,
);
catchable_error_occurred = true;
// truncate the frame stack back to the
// frame that can catch this error
self.frames.truncate(/* len = */ catching_frame_idx + 1);
continue;
}
}
return Err(err);
}
}; };
} }
} }
@ -449,12 +401,12 @@ impl<'o> VM<'o> {
// Once no more frames are present, return the stack's top value as the // Once no more frames are present, return the stack's top value as the
// result. // result.
let value = self
.stack
.pop()
.expect("tvix bug: runtime stack empty after execution");
Ok(RuntimeResult { Ok(RuntimeResult {
value: self value: value,
.stack
.pop()
.expect("tvix bug: runtime stack empty after execution"),
warnings: self.warnings, warnings: self.warnings,
}) })
} }
@ -925,10 +877,8 @@ impl<'o> VM<'o> {
} }
OpCode::OpAssertFail => { OpCode::OpAssertFail => {
frame.error( self.stack
self, .push(Value::Catchable(CatchableErrorKind::AssertionFailed));
ErrorKind::CatchableErrorKind(CatchableErrorKind::AssertionFailed),
)?;
} }
// Data-carrying operands should never be executed, // Data-carrying operands should never be executed,
@ -1214,18 +1164,26 @@ async fn add_values(co: GenCo, a: Value, b: Value) -> Result<Value, ErrorKind> {
let result = match (a, b) { let result = match (a, b) {
(Value::Path(p), v) => { (Value::Path(p), v) => {
let mut path = p.to_string_lossy().into_owned(); let mut path = p.to_string_lossy().into_owned();
let vs = generators::request_string_coerce(&co, v, CoercionKind::Weak).await; match generators::request_string_coerce(&co, v, CoercionKind::Weak).await {
path.push_str(vs.as_str()); Ok(vs) => {
crate::value::canon_path(PathBuf::from(path)).into() path.push_str(vs.as_str());
crate::value::canon_path(PathBuf::from(path)).into()
}
Err(c) => Value::Catchable(c),
}
} }
(Value::String(s1), Value::String(s2)) => Value::String(s1.concat(&s2)), (Value::String(s1), Value::String(s2)) => Value::String(s1.concat(&s2)),
(Value::String(s1), v) => Value::String( (Value::String(s1), v) => Value::String(
s1.concat(&generators::request_string_coerce(&co, v, CoercionKind::Weak).await), match generators::request_string_coerce(&co, v, CoercionKind::Weak).await {
Ok(s2) => s1.concat(&s2),
Err(c) => return Ok(Value::Catchable(c)),
},
), ),
(v, Value::String(s2)) => Value::String( (v, Value::String(s2)) => Value::String(
generators::request_string_coerce(&co, v, CoercionKind::Weak) match generators::request_string_coerce(&co, v, CoercionKind::Weak).await {
.await Ok(s1) => s1.concat(&s2),
.concat(&s2), Err(c) => return Ok(Value::Catchable(c)),
},
), ),
(a, b) => arithmetic_op!(&a, &b, +)?, (a, b) => arithmetic_op!(&a, &b, +)?,
}; };

View file

@ -109,6 +109,7 @@ impl<'de> de::Deserializer<'de> for NixDeserializer {
| Value::DeferredUpvalue(_) | Value::DeferredUpvalue(_)
| Value::UnresolvedPath(_) | Value::UnresolvedPath(_)
| Value::Json(_) | Value::Json(_)
| Value::Catchable(_)
| Value::FinaliseRequest(_) => Err(Error::Unserializable { | Value::FinaliseRequest(_) => Err(Error::Unserializable {
value_type: self.value.type_of(), value_type: self.value.type_of(),
}), }),