diff options
Diffstat (limited to 'tvix/eval/src/value/attrs.rs')
| -rw-r--r-- | tvix/eval/src/value/attrs.rs | 180 |
1 files changed, 80 insertions, 100 deletions
diff --git a/tvix/eval/src/value/attrs.rs b/tvix/eval/src/value/attrs.rs index 128e44a18b59..00b913347418 100644 --- a/tvix/eval/src/value/attrs.rs +++ b/tvix/eval/src/value/attrs.rs @@ -6,10 +6,11 @@ //! Due to this, construction and management of attribute sets has //! some peculiarities that are encapsulated within this module. use std::borrow::Borrow; +use std::collections::{btree_map, BTreeMap}; use std::iter::FromIterator; +use std::rc::Rc; use bstr::BStr; -use imbl::{ordmap, OrdMap}; use lazy_static::lazy_static; use serde::de::{Deserializer, Error, Visitor}; use serde::Deserialize; @@ -36,7 +37,7 @@ pub(super) enum AttrsRep { #[default] Empty, - Im(OrdMap<NixString, Value>), + Map(BTreeMap<NixString, Value>), /// Warning: this represents a **two**-attribute attrset, with /// attribute names "name" and "value", like `{name="foo"; @@ -48,28 +49,6 @@ pub(super) enum AttrsRep { } impl AttrsRep { - /// Retrieve reference to a mutable map inside of an attrs, - /// optionally changing the representation if required. - fn map_mut(&mut self) -> &mut OrdMap<NixString, Value> { - match self { - AttrsRep::Im(m) => m, - - AttrsRep::Empty => { - *self = AttrsRep::Im(OrdMap::new()); - self.map_mut() - } - - AttrsRep::KV { name, value } => { - *self = AttrsRep::Im(ordmap! { - NAME_S.clone() => name.clone(), - VALUE_S.clone() => value.clone() - }); - - self.map_mut() - } - } - } - fn select(&self, key: &BStr) -> Option<&Value> { match self { AttrsRep::Empty => None, @@ -80,7 +59,7 @@ impl AttrsRep { _ => None, }, - AttrsRep::Im(map) => map.get(key), + AttrsRep::Map(map) => map.get(key), } } @@ -88,18 +67,18 @@ impl AttrsRep { match self { AttrsRep::Empty => false, AttrsRep::KV { .. } => key == "name" || key == "value", - AttrsRep::Im(map) => map.contains_key(key), + AttrsRep::Map(map) => map.contains_key(key), } } } #[repr(transparent)] #[derive(Clone, Debug, Default)] -pub struct NixAttrs(pub(super) AttrsRep); +pub struct NixAttrs(pub(super) Rc<AttrsRep>); -impl From<OrdMap<NixString, Value>> for NixAttrs { - fn from(map: OrdMap<NixString, Value>) -> Self { - NixAttrs(AttrsRep::Im(map)) +impl From<AttrsRep> for NixAttrs { + fn from(rep: AttrsRep) -> Self { + NixAttrs(Rc::new(rep)) } } @@ -112,7 +91,18 @@ where where T: IntoIterator<Item = (K, V)>, { - NixAttrs(AttrsRep::Im(iter.into_iter().collect())) + AttrsRep::Map( + iter.into_iter() + .map(|(k, v)| (k.into(), v.into())) + .collect(), + ) + .into() + } +} + +impl From<BTreeMap<NixString, Value>> for NixAttrs { + fn from(map: BTreeMap<NixString, Value>) -> Self { + AttrsRep::Map(map).into() } } @@ -132,26 +122,10 @@ impl TotalDisplay for NixAttrs { f.write_str("{ ")?; - match &self.0 { - AttrsRep::KV { name, value } => { - f.write_str("name = ")?; - name.total_fmt(f, set)?; - f.write_str("; ")?; - - f.write_str("value = ")?; - value.total_fmt(f, set)?; - f.write_str("; ")?; - } - - AttrsRep::Im(map) => { - for (name, value) in map { - write!(f, "{} = ", name.ident_str())?; - value.total_fmt(f, set)?; - f.write_str("; ")?; - } - } - - AttrsRep::Empty => { /* no values to print! */ } + for (name, value) in self.iter_sorted() { + write!(f, "{} = ", name.ident_str())?; + value.total_fmt(f, set)?; + f.write_str("; ")?; } f.write_str("}") @@ -195,25 +169,22 @@ impl<'de> Deserialize<'de> for NixAttrs { impl NixAttrs { pub fn empty() -> Self { - Self(AttrsRep::Empty) + AttrsRep::Empty.into() } /// Compare two attribute sets by pointer equality. Only makes - /// sense for some attribute set reprsentations, i.e. returning + /// sense for some attribute set representations, i.e. returning /// `false` does not mean that the two attribute sets do not have /// equal *content*. pub fn ptr_eq(&self, other: &Self) -> bool { - match (&self.0, &other.0) { - (AttrsRep::Im(lhs), AttrsRep::Im(rhs)) => lhs.ptr_eq(rhs), - _ => false, - } + Rc::ptr_eq(&self.0, &other.0) } /// Return an attribute set containing the merge of the two /// provided sets. Keys from the `other` set have precedence. pub fn update(self, other: Self) -> Self { // Short-circuit on some optimal cases: - match (&self.0, &other.0) { + match (self.0.as_ref(), other.0.as_ref()) { (AttrsRep::Empty, AttrsRep::Empty) => return self, (AttrsRep::Empty, _) => return other, (_, AttrsRep::Empty) => return self, @@ -222,41 +193,44 @@ impl NixAttrs { // Explicitly handle all branches instead of falling // through, to ensure that we get at least some compiler // errors if variants are modified. - (AttrsRep::Im(_), AttrsRep::Im(_)) - | (AttrsRep::Im(_), AttrsRep::KV { .. }) - | (AttrsRep::KV { .. }, AttrsRep::Im(_)) => {} + (AttrsRep::Map(_), AttrsRep::Map(_)) + | (AttrsRep::Map(_), AttrsRep::KV { .. }) + | (AttrsRep::KV { .. }, AttrsRep::Map(_)) => {} }; // Slightly more advanced, but still optimised updates - match (self.0, other.0) { - (AttrsRep::Im(mut m), AttrsRep::KV { name, value }) => { + match (Rc::unwrap_or_clone(self.0), Rc::unwrap_or_clone(other.0)) { + (AttrsRep::Map(mut m), AttrsRep::KV { name, value }) => { m.insert(NAME_S.clone(), name); m.insert(VALUE_S.clone(), value); - NixAttrs(AttrsRep::Im(m)) + AttrsRep::Map(m).into() } - (AttrsRep::KV { name, value }, AttrsRep::Im(mut m)) => { + (AttrsRep::KV { name, value }, AttrsRep::Map(mut m)) => { match m.entry(NAME_S.clone()) { - imbl::ordmap::Entry::Vacant(e) => { + btree_map::Entry::Vacant(e) => { e.insert(name); } - imbl::ordmap::Entry::Occupied(_) => { /* name from `m` has precedence */ } + btree_map::Entry::Occupied(_) => { /* name from `m` has precedence */ } }; match m.entry(VALUE_S.clone()) { - imbl::ordmap::Entry::Vacant(e) => { + btree_map::Entry::Vacant(e) => { e.insert(value); } - imbl::ordmap::Entry::Occupied(_) => { /* value from `m` has precedence */ } + btree_map::Entry::Occupied(_) => { /* value from `m` has precedence */ } }; - NixAttrs(AttrsRep::Im(m)) + AttrsRep::Map(m).into() } // Plain merge of maps. - (AttrsRep::Im(m1), AttrsRep::Im(m2)) => NixAttrs(AttrsRep::Im(m2.union(m1))), + (AttrsRep::Map(mut m1), AttrsRep::Map(m2)) => { + m1.extend(m2); + AttrsRep::Map(m1).into() + } // Cases handled above by the borrowing match: _ => unreachable!(), @@ -265,16 +239,16 @@ impl NixAttrs { /// Return the number of key-value entries in an attrset. pub fn len(&self) -> usize { - match &self.0 { - AttrsRep::Im(map) => map.len(), + match self.0.as_ref() { + AttrsRep::Map(map) => map.len(), AttrsRep::Empty => 0, AttrsRep::KV { .. } => 2, } } pub fn is_empty(&self) -> bool { - match &self.0 { - AttrsRep::Im(map) => map.is_empty(), + match self.0.as_ref() { + AttrsRep::Map(map) => map.is_empty(), AttrsRep::Empty => true, AttrsRep::KV { .. } => false, } @@ -310,8 +284,8 @@ impl NixAttrs { /// Construct an iterator over all the key-value pairs in the attribute set. #[allow(clippy::needless_lifetimes)] pub fn iter<'a>(&'a self) -> Iter<KeyValue<'a>> { - Iter(match &self.0 { - AttrsRep::Im(map) => KeyValue::Im(map.iter()), + Iter(match &self.0.as_ref() { + AttrsRep::Map(map) => KeyValue::Map(map.iter()), AttrsRep::Empty => KeyValue::Empty, AttrsRep::KV { @@ -339,10 +313,12 @@ impl NixAttrs { /// Construct an iterator over all the keys of the attribute set pub fn keys(&self) -> Keys { - Keys(match &self.0 { + Keys(match self.0.as_ref() { AttrsRep::Empty => KeysInner::Empty, - AttrsRep::Im(m) => KeysInner::Im(m.keys()), AttrsRep::KV { .. } => KeysInner::KV(IterKV::default()), + + // TODO(tazjin): only sort when required, not always. + AttrsRep::Map(m) => KeysInner::Map(m.keys()), }) } @@ -361,7 +337,7 @@ impl NixAttrs { // Optimisation: Empty attribute set if count == 0 { - return Ok(Ok(NixAttrs(AttrsRep::Empty))); + return Ok(Ok(AttrsRep::Empty.into())); } // Optimisation: KV pattern @@ -371,14 +347,14 @@ impl NixAttrs { } } - let mut attrs = NixAttrs(AttrsRep::Im(OrdMap::new())); + let mut attrs_map = BTreeMap::new(); for _ in 0..count { let value = stack_slice.pop().unwrap(); let key = stack_slice.pop().unwrap(); match key { - Value::String(ks) => set_attr(&mut attrs, ks, value)?, + Value::String(ks) => set_attr(&mut attrs_map, ks, value)?, Value::Null => { // This is in fact valid, but leads to the value @@ -393,13 +369,13 @@ impl NixAttrs { } } - Ok(Ok(attrs)) + Ok(Ok(AttrsRep::Map(attrs_map).into())) } /// Construct an optimized "KV"-style attribute set given the value for the /// `"name"` key, and the value for the `"value"` key pub(crate) fn from_kv(name: Value, value: Value) -> Self { - NixAttrs(AttrsRep::KV { name, value }) + AttrsRep::KV { name, value }.into() } } @@ -408,12 +384,12 @@ impl IntoIterator for NixAttrs { type IntoIter = OwnedAttrsIterator; fn into_iter(self) -> Self::IntoIter { - match self.0 { + match Rc::unwrap_or_clone(self.0) { AttrsRep::Empty => OwnedAttrsIterator(IntoIterRepr::Empty), AttrsRep::KV { name, value } => OwnedAttrsIterator(IntoIterRepr::Finite( vec![(NAME_REF.clone(), name), (VALUE_REF.clone(), value)].into_iter(), )), - AttrsRep::Im(map) => OwnedAttrsIterator(IntoIterRepr::Im(map.into_iter())), + AttrsRep::Map(map) => OwnedAttrsIterator(IntoIterRepr::Map(map.into_iter())), } } } @@ -452,13 +428,17 @@ fn attempt_optimise_kv(slice: &mut [Value]) -> Option<NixAttrs> { /// Set an attribute on an in-construction attribute set, while /// checking against duplicate keys. -fn set_attr(attrs: &mut NixAttrs, key: NixString, value: Value) -> Result<(), ErrorKind> { - match attrs.0.map_mut().entry(key) { - imbl::ordmap::Entry::Occupied(entry) => Err(ErrorKind::DuplicateAttrsKey { +fn set_attr( + map: &mut BTreeMap<NixString, Value>, + key: NixString, + value: Value, +) -> Result<(), ErrorKind> { + match map.entry(key) { + btree_map::Entry::Occupied(entry) => Err(ErrorKind::DuplicateAttrsKey { key: entry.key().to_string(), }), - imbl::ordmap::Entry::Vacant(entry) => { + btree_map::Entry::Vacant(entry) => { entry.insert(value); Ok(()) } @@ -496,7 +476,7 @@ pub enum KeyValue<'a> { at: IterKV, }, - Im(imbl::ordmap::Iter<'a, NixString, Value>), + Map(btree_map::Iter<'a, NixString, Value>), } /// Iterator over a Nix attribute set. @@ -510,7 +490,7 @@ impl<'a> Iterator for Iter<KeyValue<'a>> { fn next(&mut self) -> Option<Self::Item> { match &mut self.0 { - KeyValue::Im(inner) => inner.next(), + KeyValue::Map(inner) => inner.next(), KeyValue::Empty => None, KeyValue::KV { name, value, at } => match at { @@ -535,7 +515,7 @@ impl<'a> ExactSizeIterator for Iter<KeyValue<'a>> { match &self.0 { KeyValue::Empty => 0, KeyValue::KV { .. } => 2, - KeyValue::Im(inner) => inner.len(), + KeyValue::Map(inner) => inner.len(), } } } @@ -543,7 +523,7 @@ impl<'a> ExactSizeIterator for Iter<KeyValue<'a>> { enum KeysInner<'a> { Empty, KV(IterKV), - Im(imbl::ordmap::Keys<'a, NixString, Value>), + Map(btree_map::Keys<'a, NixString, Value>), } pub struct Keys<'a>(KeysInner<'a>); @@ -563,7 +543,7 @@ impl<'a> Iterator for Keys<'a> { Some(&VALUE_REF) } KeysInner::KV(IterKV::Done) => None, - KeysInner::Im(m) => m.next(), + KeysInner::Map(m) => m.next(), } } } @@ -583,7 +563,7 @@ impl<'a> ExactSizeIterator for Keys<'a> { match &self.0 { KeysInner::Empty => 0, KeysInner::KV(_) => 2, - KeysInner::Im(m) => m.len(), + KeysInner::Map(m) => m.len(), } } } @@ -592,7 +572,7 @@ impl<'a> ExactSizeIterator for Keys<'a> { pub enum IntoIterRepr { Empty, Finite(std::vec::IntoIter<(NixString, Value)>), - Im(imbl::ordmap::ConsumingIter<(NixString, Value)>), + Map(btree_map::IntoIter<NixString, Value>), } /// Wrapper type which hides the internal implementation details from @@ -607,7 +587,7 @@ impl Iterator for OwnedAttrsIterator { match &mut self.0 { IntoIterRepr::Empty => None, IntoIterRepr::Finite(inner) => inner.next(), - IntoIterRepr::Im(inner) => inner.next(), + IntoIterRepr::Map(m) => m.next(), } } } @@ -617,7 +597,7 @@ impl ExactSizeIterator for OwnedAttrsIterator { match &self.0 { IntoIterRepr::Empty => 0, IntoIterRepr::Finite(inner) => inner.len(), - IntoIterRepr::Im(inner) => inner.len(), + IntoIterRepr::Map(inner) => inner.len(), } } } @@ -627,7 +607,7 @@ impl DoubleEndedIterator for OwnedAttrsIterator { match &mut self.0 { IntoIterRepr::Empty => None, IntoIterRepr::Finite(inner) => inner.next_back(), - IntoIterRepr::Im(inner) => inner.next_back(), + IntoIterRepr::Map(inner) => inner.next_back(), } } } |