diff options
-rw-r--r-- | dhall/src/syntax/ast/text.rs | 4 | ||||
-rw-r--r-- | serde_dhall/src/lib.rs | 22 | ||||
-rw-r--r-- | serde_dhall/src/serde.rs | 109 | ||||
-rw-r--r-- | serde_dhall/src/static_type.rs | 11 | ||||
-rw-r--r-- | serde_dhall/tests/de.rs | 85 |
5 files changed, 210 insertions, 21 deletions
diff --git a/dhall/src/syntax/ast/text.rs b/dhall/src/syntax/ast/text.rs index fb390ee..83aaf9a 100644 --- a/dhall/src/syntax/ast/text.rs +++ b/dhall/src/syntax/ast/text.rs @@ -97,6 +97,10 @@ impl<SubExpr> InterpolatedText<SubExpr> { &self.head } + pub fn tail(&self) -> &Vec<(SubExpr, String)> { + &self.tail + } + pub fn head_mut(&mut self) -> &mut String { &mut self.head } diff --git a/serde_dhall/src/lib.rs b/serde_dhall/src/lib.rs index 45aca57..0878471 100644 --- a/serde_dhall/src/lib.rs +++ b/serde_dhall/src/lib.rs @@ -64,6 +64,28 @@ //! # } //! ``` //! +//! # Type correspondence +//! +//! The following Dhall types correspond to the following Rust types: +//! +//! Dhall | Rust +//! -------|------ +//! `Bool` | `bool` +//! `Natural` | `u64`, `u32`, ... +//! `Integer` | `i64`, `i32`, ... +//! `Double` | `f64`, `f32`, ... +//! `Text` | `String` +//! `List T` | `Vec<T>` +//! `Optional T` | `Option<T>` +//! `{ x: T, y: U }` | structs +//! `{ _1: T, _2: U }` | `(T, U)`, structs +//! `{ x: T, y: T }` | `HashMap<String, T>`, structs +//! `< x: T \| y: U >` | enums +//! `T -> U` | unsupported +//! `Prelude.JSON.Type` | unsupported +//! `Prelude.Map.Type T U` | unsupported +//! +//! //! # Replacing `serde_json` or `serde_yaml` //! //! If you used to consume JSON or YAML, you only need to replace [serde_json::from_str] or diff --git a/serde_dhall/src/serde.rs b/serde_dhall/src/serde.rs index 99b9014..2e449df 100644 --- a/serde_dhall/src/serde.rs +++ b/serde_dhall/src/serde.rs @@ -1,5 +1,9 @@ use std::borrow::Cow; +use serde::de::value::{ + MapAccessDeserializer, MapDeserializer, SeqDeserializer, +}; + use dhall::semantics::phase::NormalizedExpr; use dhall::syntax::ExprKind; @@ -28,43 +32,112 @@ impl<'de: 'a, 'a> serde::de::IntoDeserializer<'de, Error> for Deserializer<'a> { impl<'de: 'a, 'a> serde::Deserializer<'de> for Deserializer<'a> { type Error = Error; + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value> where V: serde::de::Visitor<'de>, { use std::convert::TryInto; use ExprKind::*; - match self.0.as_ref().as_ref() { - NaturalLit(n) => { - if let Ok(n64) = (*n).try_into() { - visitor.visit_u64(n64) - } else if let Ok(n32) = (*n).try_into() { - visitor.visit_u32(n32) + let expr = self.0.as_ref(); + let not_serde_compatible = || { + Err(Error::Deserialize(format!( + "this cannot be deserialized into the serde data model: {}", + expr + ))) + }; + + match expr.as_ref() { + BoolLit(x) => visitor.visit_bool(*x), + NaturalLit(x) => { + if let Ok(x64) = (*x).try_into() { + visitor.visit_u64(x64) + } else if let Ok(x32) = (*x).try_into() { + visitor.visit_u32(x32) } else { unimplemented!() } } - IntegerLit(n) => { - if let Ok(n64) = (*n).try_into() { - visitor.visit_i64(n64) - } else if let Ok(n32) = (*n).try_into() { - visitor.visit_i32(n32) + IntegerLit(x) => { + if let Ok(x64) = (*x).try_into() { + visitor.visit_i64(x64) + } else if let Ok(x32) = (*x).try_into() { + visitor.visit_i32(x32) } else { unimplemented!() } } - RecordLit(m) => visitor.visit_map( - serde::de::value::MapDeserializer::new(m.iter().map( - |(k, v)| (k.as_ref(), Deserializer(Cow::Borrowed(v))), - )), - ), - _ => unimplemented!(), + DoubleLit(x) => visitor.visit_f64((*x).into()), + TextLit(x) => { + // Normal form ensures that the tail is empty. + assert!(x.tail().is_empty()); + visitor.visit_str(x.head()) + } + EmptyListLit(..) => { + visitor.visit_seq(SeqDeserializer::new(None::<()>.into_iter())) + } + NEListLit(xs) => visitor.visit_seq(SeqDeserializer::new( + xs.iter().map(|x| Deserializer(Cow::Borrowed(x))), + )), + SomeLit(x) => visitor.visit_some(Deserializer(Cow::Borrowed(x))), + App(f, x) => match f.as_ref() { + Builtin(dhall::syntax::Builtin::OptionalNone) => { + visitor.visit_none() + } + Field(y, name) => match y.as_ref() { + UnionType(..) => { + let name: String = name.into(); + visitor.visit_enum(MapAccessDeserializer::new( + MapDeserializer::new( + Some((name, Deserializer(Cow::Borrowed(x)))) + .into_iter(), + ), + )) + } + _ => not_serde_compatible(), + }, + _ => not_serde_compatible(), + }, + RecordLit(m) => visitor + .visit_map(MapDeserializer::new(m.iter().map(|(k, v)| { + (k.as_ref(), Deserializer(Cow::Borrowed(v))) + }))), + Field(y, name) => match y.as_ref() { + UnionType(..) => { + let name: String = name.into(); + visitor.visit_enum(MapAccessDeserializer::new( + MapDeserializer::new(Some((name, ())).into_iter()), + )) + } + _ => not_serde_compatible(), + }, + Const(..) | Var(..) | Lam(..) | Pi(..) | Let(..) | Annot(..) + | Assert(..) | Builtin(..) | BinOp(..) | BoolIf(..) + | RecordType(..) | UnionType(..) | Merge(..) | ToMap(..) + | Projection(..) | ProjectionByExpr(..) | Completion(..) + | Import(..) | Embed(..) => not_serde_compatible(), + } + } + + fn deserialize_tuple<V>(self, _: usize, visitor: V) -> Result<V::Value> + where + V: serde::de::Visitor<'de>, + { + use ExprKind::*; + let expr = self.0.as_ref(); + + match expr.as_ref() { + // Blindly takes keys in sorted order. + RecordLit(m) => visitor.visit_seq(SeqDeserializer::new( + m.iter().map(|(_, v)| Deserializer(Cow::Borrowed(v))), + )), + _ => self.deserialize_any(visitor), } } serde::forward_to_deserialize_any! { bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string - bytes byte_buf option unit unit_struct newtype_struct seq tuple + bytes byte_buf option unit unit_struct newtype_struct seq tuple_struct map struct enum identifier ignored_any } } diff --git a/serde_dhall/src/static_type.rs b/serde_dhall/src/static_type.rs index 1323aa3..1eb9150 100644 --- a/serde_dhall/src/static_type.rs +++ b/serde_dhall/src/static_type.rs @@ -1,4 +1,4 @@ -use dhall::syntax::{Builtin, Integer, Natural}; +use dhall::syntax::Builtin; use crate::Value; @@ -28,9 +28,14 @@ macro_rules! derive_builtin { } derive_builtin!(bool, Bool); -derive_builtin!(Natural, Natural); +derive_builtin!(usize, Natural); derive_builtin!(u64, Natural); -derive_builtin!(Integer, Integer); +derive_builtin!(u32, Natural); +derive_builtin!(isize, Integer); +derive_builtin!(i64, Integer); +derive_builtin!(i32, Integer); +derive_builtin!(f64, Double); +derive_builtin!(f32, Double); derive_builtin!(String, Text); impl<A, B> StaticType for (A, B) diff --git a/serde_dhall/tests/de.rs b/serde_dhall/tests/de.rs new file mode 100644 index 0000000..41a44bd --- /dev/null +++ b/serde_dhall/tests/de.rs @@ -0,0 +1,85 @@ +use serde::Deserialize; +use serde_dhall::{from_str, from_str_auto_type, StaticType}; + +#[test] +fn test_de_typed() { + fn parse<T: serde_dhall::de::Deserialize + StaticType>(s: &str) -> T { + from_str_auto_type(s).unwrap() + } + + assert_eq!(parse::<bool>("True"), true); + + assert_eq!(parse::<u64>("1"), 1); + assert_eq!(parse::<u32>("1"), 1); + assert_eq!(parse::<usize>("1"), 1); + + assert_eq!(parse::<i64>("+1"), 1); + assert_eq!(parse::<i32>("+1"), 1); + assert_eq!(parse::<isize>("+1"), 1); + + assert_eq!(parse::<f64>("1.0"), 1.0); + assert_eq!(parse::<f32>("1.0"), 1.0); + + assert_eq!(parse::<String>(r#""foo""#), "foo".to_owned()); + assert_eq!(parse::<Vec<u64>>("[] : List Natural"), vec![]); + assert_eq!(parse::<Vec<u64>>("[1, 2]"), vec![1, 2]); + assert_eq!(parse::<Option<u64>>("None Natural"), None); + assert_eq!(parse::<Option<u64>>("Some 1"), Some(1)); + + assert_eq!( + parse::<(u64, String)>(r#"{ _1 = 1, _2 = "foo" }"#), + (1, "foo".to_owned()) + ); + + #[derive(Debug, PartialEq, Eq, Deserialize, StaticType)] + struct Foo { + x: u64, + y: i64, + } + assert_eq!(parse::<Foo>("{ x = 1, y = -2 }"), Foo { x: 1, y: -2 }); + + #[derive(Debug, PartialEq, Eq, Deserialize, StaticType)] + enum Bar { + X(u64), + Y(i64), + } + assert_eq!(parse::<Bar>("< X: Natural | Y: Integer >.X 1"), Bar::X(1)); + + #[derive(Debug, PartialEq, Eq, Deserialize, StaticType)] + enum Baz { + X, + Y(i64), + } + assert_eq!(parse::<Baz>("< X | Y: Integer >.X"), Baz::X); +} + +#[test] +fn test_de_untyped() { + fn parse<T: serde_dhall::de::Deserialize>(s: &str) -> T { + from_str(s).unwrap() + } + + // Test tuples on record of wrong type + assert_eq!( + parse::<(u64, String, isize)>(r#"{ y = "foo", x = 1, z = +42 }"#), + (1, "foo".to_owned(), 42) + ); + + use std::collections::HashMap; + let mut expected_map = HashMap::new(); + expected_map.insert("x".to_string(), 1); + expected_map.insert("y".to_string(), 2); + assert_eq!( + parse::<HashMap<String, usize>>("{ x = 1, y = 2 }"), + expected_map + ); + + use std::collections::BTreeMap; + let mut expected_map = BTreeMap::new(); + expected_map.insert("x".to_string(), 1); + expected_map.insert("y".to_string(), 2); + assert_eq!( + parse::<BTreeMap<String, usize>>("{ x = 1, y = 2 }"), + expected_map + ); +} |