separate decode from string/bytes for all data functions; and encode for json, toml, yaml via serde (#1935)

9 files changed, 387 insertions, 103 deletions

diff --git a/assets/files/toml-types.toml b/assets/files/toml-types.toml
index 93feead8..aaed23ee 100644
--- a/assets/files/toml-types.toml
+++ b/assets/files/toml-types.toml
@@ -3,6 +3,9 @@ integer = 42
 float = 3.14
 boolean = true
 date_time = 2023-02-01T15:38:57Z
+date_time2 = 2023-02-01T15:38:57
+date = 2023-02-01
+time = 15:38:57
 array = [1, "string", 3.0, false]
 inline_table = { first = "amazing", second = "greater" }
 
diff --git a/crates/typst-library/Cargo.toml b/crates/typst-library/Cargo.toml
index 06b4bd2d..aa1de020 100644
--- a/crates/typst-library/Cargo.toml
+++ b/crates/typst-library/Cargo.toml
@@ -41,7 +41,7 @@ serde_yaml = "0.8"
 smallvec = "1.10"
 syntect = { version = "5", default-features = false, features = ["parsing", "regex-fancy", "plist-load", "yaml-load"] }
 time = { version = "0.3.20", features = ["formatting"] }
-toml = { version = "0.7.3", default-features = false, features = ["parse"] }
+toml = { version = "0.7.4"}
 tracing = "0.1.37"
 ttf-parser = "0.18.1"
 typed-arena = "2"
diff --git a/crates/typst-library/src/compute/data.rs b/crates/typst-library/src/compute/data.rs
index ceeb48d1..944baff3 100644
--- a/crates/typst-library/src/compute/data.rs
+++ b/crates/typst-library/src/compute/data.rs
@@ -1,5 +1,5 @@
 use typst::diag::{format_xml_like_error, FileError};
-use typst::eval::{Bytes, Datetime};
+use typst::eval::Bytes;
 
 use crate::prelude::*;
 
@@ -65,6 +65,15 @@ pub enum Readable {
     Bytes(Bytes),
 }
 
+impl Readable {
+    fn as_slice(&self) -> &[u8] {
+        match self {
+            Readable::Bytes(v) => v,
+            Readable::Str(v) => v.as_bytes(),
+        }
+    }
+}
+
 cast! {
     Readable,
     self => match self {
@@ -105,6 +114,10 @@ impl From<Readable> for Bytes {
 /// Display: CSV
 /// Category: data-loading
 #[func]
+#[scope(
+    scope.define("decode", csv_decode_func());
+    scope
+)]
 pub fn csv(
     /// Path to a CSV file.
     path: Spanned<EcoString>,
@@ -119,11 +132,27 @@ pub fn csv(
     let Spanned { v: path, span } = path;
     let id = vm.location().join(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
+    csv_decode(Spanned::new(Readable::Bytes(data), span), delimiter)
+}
 
+/// Reads structured data from a CSV string/bytes.
+///
+/// Display: CSV
+/// Category: data-loading
+#[func]
+pub fn csv_decode(
+    /// CSV data.
+    data: Spanned<Readable>,
+    /// The delimiter that separates columns in the CSV file.
+    /// Must be a single ASCII character.
+    #[named]
+    #[default]
+    delimiter: Delimiter,
+) -> SourceResult<Array> {
+    let Spanned { v: data, span } = data;
     let mut builder = csv::ReaderBuilder::new();
     builder.has_headers(false);
     builder.delimiter(delimiter.0 as u8);
-
     let mut reader = builder.from_reader(data.as_slice());
     let mut array = Array::new();
 
@@ -221,6 +250,11 @@ fn format_csv_error(error: csv::Error, line: usize) -> EcoString {
 /// Display: JSON
 /// Category: data-loading
 #[func]
+#[scope(
+    scope.define("decode", json_decode_func());
+    scope.define("encode", json_encode_func());
+    scope
+)]
 pub fn json(
     /// Path to a JSON file.
     path: Spanned<EcoString>,
@@ -230,30 +264,48 @@ pub fn json(
     let Spanned { v: path, span } = path;
     let id = vm.location().join(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
-    let value: serde_json::Value =
-        serde_json::from_slice(&data).map_err(format_json_error).at(span)?;
-    Ok(convert_json(value))
+    json_decode(Spanned::new(Readable::Bytes(data), span))
 }
 
-/// Convert a JSON value to a Typst value.
-fn convert_json(value: serde_json::Value) -> Value {
-    match value {
-        serde_json::Value::Null => Value::None,
-        serde_json::Value::Bool(v) => v.into_value(),
-        serde_json::Value::Number(v) => match v.as_i64() {
-            Some(int) => int.into_value(),
-            None => v.as_f64().unwrap_or(f64::NAN).into_value(),
-        },
-        serde_json::Value::String(v) => v.into_value(),
-        serde_json::Value::Array(v) => {
-            v.into_iter().map(convert_json).collect::<Array>().into_value()
-        }
-        serde_json::Value::Object(v) => v
-            .into_iter()
-            .map(|(key, value)| (key.into(), convert_json(value)))
-            .collect::<Dict>()
-            .into_value(),
+/// Reads structured data from a JSON string/bytes.
+///
+/// Display: JSON
+/// Category: data-loading
+#[func]
+pub fn json_decode(
+    /// JSON data.
+    data: Spanned<Readable>,
+) -> SourceResult<Value> {
+    let Spanned { v: data, span } = data;
+    let value: Value = serde_json::from_slice(data.as_slice())
+        .map_err(format_json_error)
+        .at(span)?;
+    Ok(value)
+}
+
+/// Encode structured data into a JSON string.
+///
+/// Display: JSON
+/// Category: data-loading
+#[func]
+pub fn json_encode(
+    /// Value to be encoded.
+    value: Spanned<Value>,
+    /// Whether to pretty print the JSON with newlines and indentation.
+    #[named]
+    #[default(true)]
+    pretty: bool,
+) -> SourceResult<Str> {
+    let Spanned { v: value, span } = value;
+
+    if pretty {
+        serde_json::to_string_pretty(&value)
+    } else {
+        serde_json::to_string(&value)
     }
+    .map(|v| v.into())
+    .map_err(|e| eco_format!("failed to encode value as json: {e}"))
+    .at(span)
 }
 
 /// Format the user-facing JSON error message.
@@ -286,6 +338,11 @@ fn format_json_error(error: serde_json::Error) -> EcoString {
 /// Display: TOML
 /// Category: data-loading
 #[func]
+#[scope(
+    scope.define("decode", toml_decode_func());
+    scope.define("encode", toml_encode_func());
+    scope
+)]
 pub fn toml(
     /// Path to a TOML file.
     path: Spanned<EcoString>,
@@ -296,48 +353,46 @@ pub fn toml(
     let id = vm.location().join(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
 
-    let raw = std::str::from_utf8(&data)
+    toml_decode(Spanned::new(Readable::Bytes(data), span))
+}
+
+/// Reads structured data from a TOML string/bytes.
+///
+/// Display: TOML
+/// Category: data-loading
+#[func]
+pub fn toml_decode(
+    /// TOML data.
+    data: Spanned<Readable>,
+) -> SourceResult<Value> {
+    let Spanned { v: data, span } = data;
+    let raw = std::str::from_utf8(data.as_slice())
         .map_err(|_| "file is not valid utf-8")
         .at(span)?;
 
-    let value: toml::Value = toml::from_str(raw).map_err(format_toml_error).at(span)?;
-    Ok(convert_toml(value))
+    let value: Value = toml::from_str(raw).map_err(format_toml_error).at(span)?;
+    Ok(value)
 }
 
-/// Convert a TOML value to a Typst value.
-fn convert_toml(value: toml::Value) -> Value {
-    match value {
-        toml::Value::String(v) => v.into_value(),
-        toml::Value::Integer(v) => v.into_value(),
-        toml::Value::Float(v) => v.into_value(),
-        toml::Value::Boolean(v) => v.into_value(),
-        toml::Value::Array(v) => {
-            v.into_iter().map(convert_toml).collect::<Array>().into_value()
-        }
-        toml::Value::Table(v) => v
-            .into_iter()
-            .map(|(key, value)| (key.into(), convert_toml(value)))
-            .collect::<Dict>()
-            .into_value(),
-        toml::Value::Datetime(v) => match (v.date, v.time) {
-            (None, None) => Value::None,
-            (Some(date), None) => {
-                Datetime::from_ymd(date.year as i32, date.month, date.day).into_value()
-            }
-            (None, Some(time)) => {
-                Datetime::from_hms(time.hour, time.minute, time.second).into_value()
-            }
-            (Some(date), Some(time)) => Datetime::from_ymd_hms(
-                date.year as i32,
-                date.month,
-                date.day,
-                time.hour,
-                time.minute,
-                time.second,
-            )
-            .into_value(),
-        },
-    }
+/// Encode structured data into a TOML string.
+///
+/// Display: TOML
+/// Category: data-loading
+#[func]
+pub fn toml_encode(
+    /// Value to be encoded.
+    value: Spanned<Value>,
+    /// Apply a default pretty policy to the document.
+    #[named]
+    #[default(true)]
+    pretty: bool,
+) -> SourceResult<Str> {
+    let Spanned { v: value, span } = value;
+
+    if pretty { toml::to_string_pretty(&value) } else { toml::to_string(&value) }
+        .map(|v| v.into())
+        .map_err(|e| eco_format!("failed to encode value as toml: {e}"))
+        .at(span)
 }
 
 /// Format the user-facing TOML error message.
@@ -395,6 +450,11 @@ fn format_toml_error(error: toml::de::Error) -> EcoString {
 /// Display: YAML
 /// Category: data-loading
 #[func]
+#[scope(
+    scope.define("decode", yaml_decode_func());
+    scope.define("encode", yaml_encode_func());
+    scope
+)]
 pub fn yaml(
     /// Path to a YAML file.
     path: Spanned<EcoString>,
@@ -404,41 +464,40 @@ pub fn yaml(
     let Spanned { v: path, span } = path;
     let id = vm.location().join(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
-    let value: serde_yaml::Value =
-        serde_yaml::from_slice(&data).map_err(format_yaml_error).at(span)?;
-    Ok(convert_yaml(value))
+    yaml_decode(Spanned::new(Readable::Bytes(data), span))
 }
 
-/// Convert a YAML value to a Typst value.
-fn convert_yaml(value: serde_yaml::Value) -> Value {
-    match value {
-        serde_yaml::Value::Null => Value::None,
-        serde_yaml::Value::Bool(v) => v.into_value(),
-        serde_yaml::Value::Number(v) => match v.as_i64() {
-            Some(int) => int.into_value(),
-            None => v.as_f64().unwrap_or(f64::NAN).into_value(),
-        },
-        serde_yaml::Value::String(v) => v.into_value(),
-        serde_yaml::Value::Sequence(v) => {
-            v.into_iter().map(convert_yaml).collect::<Array>().into_value()
-        }
-        serde_yaml::Value::Mapping(v) => v
-            .into_iter()
-            .map(|(key, value)| (convert_yaml_key(key), convert_yaml(value)))
-            .filter_map(|(key, value)| key.map(|key| (key, value)))
-            .collect::<Dict>()
-            .into_value(),
-    }
+/// Reads structured data from a YAML string/bytes.
+///
+/// Display: YAML
+/// Category: data-loading
+#[func]
+pub fn yaml_decode(
+    /// YAML data.
+    data: Spanned<Readable>,
+) -> SourceResult<Value> {
+    let Spanned { v: data, span } = data;
+    let value: Value = serde_yaml::from_slice(data.as_slice())
+        .map_err(format_yaml_error)
+        .at(span)?;
+    Ok(value)
 }
 
-/// Converts an arbitrary YAML mapping key into a Typst Dict Key.
-/// Currently it only does so for strings, everything else
-/// returns None
-fn convert_yaml_key(key: serde_yaml::Value) -> Option<Str> {
-    match key {
-        serde_yaml::Value::String(v) => Some(Str::from(v)),
-        _ => None,
-    }
+/// Encode structured data into a yaml string.
+///
+/// Display: YAML
+/// Category: data-loading
+#[func]
+pub fn yaml_encode(
+    /// Value to be encoded.
+    value: Spanned<Value>,
+) -> SourceResult<Str> {
+    let Spanned { v: value, span } = value;
+
+    serde_yaml::to_string(&value)
+        .map(|v| v.into())
+        .map_err(|e| eco_format!("failed to encode value as yaml: {e}"))
+        .at(span)
 }
 
 /// Format the user-facing YAML error message.
@@ -498,6 +557,10 @@ fn format_yaml_error(error: serde_yaml::Error) -> EcoString {
 /// Display: XML
 /// Category: data-loading
 #[func]
+#[scope(
+    scope.define("decode", xml_decode_func());
+    scope
+)]
 pub fn xml(
     /// Path to an XML file.
     path: Spanned<EcoString>,
@@ -507,7 +570,22 @@ pub fn xml(
     let Spanned { v: path, span } = path;
     let id = vm.location().join(&path).at(span)?;
     let data = vm.world().file(id).at(span)?;
-    let text = std::str::from_utf8(&data).map_err(FileError::from).at(span)?;
+    xml_decode(Spanned::new(Readable::Bytes(data), span))
+}
+
+/// Reads structured data from an XML string/bytes.
+///
+/// Display: XML
+/// Category: data-loading
+#[func]
+pub fn xml_decode(
+    /// XML data.
+    data: Spanned<Readable>,
+) -> SourceResult<Value> {
+    let Spanned { v: data, span } = data;
+    let text = std::str::from_utf8(data.as_slice())
+        .map_err(FileError::from)
+        .at(span)?;
     let document = roxmltree::Document::parse(text).map_err(format_xml_error).at(span)?;
     Ok(convert_xml(document.root()))
 }
diff --git a/crates/typst/Cargo.toml b/crates/typst/Cargo.toml
index 15b2e9a1..74e7cb49 100644
--- a/crates/typst/Cargo.toml
+++ b/crates/typst/Cargo.toml
@@ -43,7 +43,7 @@ siphasher = "0.3"
 subsetter = "0.1.1"
 svg2pdf = "0.6"
 tiny-skia = "0.9.0"
-toml = { version = "0.7.3", default-features = false, features = ["parse"] }
+toml = { version = "0.7.4", default-features = false, features = ["parse"] }
 tracing = "0.1.37"
 ttf-parser = "0.18.1"
 unicode-general-category = "0.6"
@@ -54,7 +54,7 @@ unscanny = "0.1"
 usvg = { version = "0.32", default-features = false, features = ["text"] }
 xmlwriter = "0.1.0"
 xmp-writer = "0.1"
-time = { version = "0.3.20", features = ["std", "formatting"] }
+time = { version = "0.3.20", features = ["std", "formatting", "macros"] }
 wasmi = "0.30.0"
 xmlparser = "0.13.5"
 
diff --git a/crates/typst/src/eval/array.rs b/crates/typst/src/eval/array.rs
index 9afae865..35060cdc 100644
--- a/crates/typst/src/eval/array.rs
+++ b/crates/typst/src/eval/array.rs
@@ -3,7 +3,7 @@ use std::fmt::{self, Debug, Formatter};
 use std::ops::{Add, AddAssign};
 
 use ecow::{eco_format, EcoString, EcoVec};
-use serde::Serialize;
+use serde::{Deserialize, Serialize};
 
 use super::{ops, Args, CastInfo, FromValue, Func, IntoValue, Reflect, Value, Vm};
 use crate::diag::{At, SourceResult, StrResult};
@@ -35,7 +35,8 @@ pub use crate::__array as array;
 pub use ecow::eco_vec;
 
 /// A reference counted array with value semantics.
-#[derive(Default, Clone, PartialEq, Hash, Serialize)]
+#[derive(Default, Clone, PartialEq, Hash, Serialize, Deserialize)]
+#[serde(transparent)]
 pub struct Array(EcoVec<Value>);
 
 impl Array {
diff --git a/crates/typst/src/eval/dict.rs b/crates/typst/src/eval/dict.rs
index 41d72d98..a1a3948a 100644
--- a/crates/typst/src/eval/dict.rs
+++ b/crates/typst/src/eval/dict.rs
@@ -4,7 +4,7 @@ use std::ops::{Add, AddAssign};
 use std::sync::Arc;
 
 use ecow::{eco_format, EcoString};
-use serde::{Serialize, Serializer};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 
 use super::{array, Array, Str, Value};
 use crate::diag::StrResult;
@@ -198,6 +198,15 @@ impl Serialize for Dict {
     }
 }
 
+impl<'de> Deserialize<'de> for Dict {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        Ok(IndexMap::<Str, Value>::deserialize(deserializer)?.into())
+    }
+}
+
 impl Extend<(Str, Value)> for Dict {
     fn extend<T: IntoIterator<Item = (Str, Value)>>(&mut self, iter: T) {
         Arc::make_mut(&mut self.0).extend(iter);
diff --git a/crates/typst/src/eval/str.rs b/crates/typst/src/eval/str.rs
index 21dc3b68..30139f10 100644
--- a/crates/typst/src/eval/str.rs
+++ b/crates/typst/src/eval/str.rs
@@ -4,7 +4,7 @@ use std::hash::{Hash, Hasher};
 use std::ops::{Add, AddAssign, Deref, Range};
 
 use ecow::EcoString;
-use serde::Serialize;
+use serde::{Deserialize, Serialize};
 use unicode_segmentation::UnicodeSegmentation;
 
 use super::{cast, dict, Args, Array, Dict, Func, IntoValue, Value, Vm};
@@ -26,7 +26,8 @@ pub use crate::__format_str as format_str;
 pub use ecow::eco_format;
 
 /// An immutable reference counted string.
-#[derive(Default, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Serialize)]
+#[derive(Default, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Serialize, Deserialize)]
+#[serde(transparent)]
 pub struct Str(EcoString);
 
 impl Str {
diff --git a/crates/typst/src/eval/value.rs b/crates/typst/src/eval/value.rs
index 6a3fcd3c..9cd268fa 100644
--- a/crates/typst/src/eval/value.rs
+++ b/crates/typst/src/eval/value.rs
@@ -5,14 +5,18 @@ use std::hash::{Hash, Hasher};
 use std::sync::Arc;
 
 use ecow::eco_format;
-use serde::{Serialize, Serializer};
+use serde::de::value::{MapAccessDeserializer, SeqAccessDeserializer};
+use serde::de::{Error, MapAccess, SeqAccess, Visitor};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use siphasher::sip128::{Hasher128, SipHasher13};
+use time::macros::format_description;
 
 use super::{
     cast, fields, format_str, ops, Args, Array, Bytes, CastInfo, Content, Dict,
     FromValue, Func, IntoValue, Module, Reflect, Str, Symbol,
 };
 use crate::diag::StrResult;
+use crate::eval::Datetime;
 use crate::geom::{Abs, Angle, Color, Em, Fr, Length, Ratio, Rel};
 use crate::model::{Label, Styles};
 use crate::syntax::{ast, Span};
@@ -274,6 +278,176 @@ impl Serialize for Value {
     }
 }
 
+fn parse_toml_date(dict: &Dict) -> Option<Datetime> {
+    if dict.len() != 1 || !dict.contains("$__toml_private_datetime") {
+        return None;
+    }
+
+    let Ok(s) = String::from_value(dict.at("$__toml_private_datetime", None).unwrap()) else {
+        return None;
+    };
+
+    if let Ok(d) = time::PrimitiveDateTime::parse(
+        &s,
+        &format_description!("[year]-[month]-[day]T[hour]:[minute]:[second]Z"),
+    ) {
+        Some(
+            Datetime::from_ymd_hms(
+                d.year(),
+                d.month() as u8,
+                d.day(),
+                d.hour(),
+                d.minute(),
+                d.second(),
+            )
+            .unwrap(),
+        )
+    } else if let Ok(d) = time::PrimitiveDateTime::parse(
+        &s,
+        &format_description!("[year]-[month]-[day]T[hour]:[minute]:[second]"),
+    ) {
+        Some(
+            Datetime::from_ymd_hms(
+                d.year(),
+                d.month() as u8,
+                d.day(),
+                d.hour(),
+                d.minute(),
+                d.second(),
+            )
+            .unwrap(),
+        )
+    } else if let Ok(d) =
+        time::Date::parse(&s, &format_description!("[year]-[month]-[day]"))
+    {
+        Some(Datetime::from_ymd(d.year(), d.month() as u8, d.day()).unwrap())
+    } else if let Ok(d) =
+        time::Time::parse(&s, &format_description!("[hour]:[minute]:[second]"))
+    {
+        Some(Datetime::from_hms(d.hour(), d.minute(), d.second()).unwrap())
+    } else {
+        None
+    }
+}
+
+struct ValueVisitor;
+
+impl<'de> Visitor<'de> for ValueVisitor {
+    type Value = Value;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("a typst value")
+    }
+
+    fn visit_bool<E: Error>(self, v: bool) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_i8<E: Error>(self, v: i8) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_i16<E: Error>(self, v: i16) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_i32<E: Error>(self, v: i32) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_i64<E: Error>(self, v: i64) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_u8<E: Error>(self, v: u8) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_u16<E: Error>(self, v: u16) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_u32<E: Error>(self, v: u32) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_u64<E: Error>(self, v: u64) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_f32<E: Error>(self, v: f32) -> Result<Self::Value, E> {
+        Ok((v as f64).into_value())
+    }
+
+    fn visit_f64<E: Error>(self, v: f64) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_char<E: Error>(self, v: char) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_str<E: Error>(self, v: &str) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_borrowed_str<E: Error>(self, v: &'de str) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_string<E: Error>(self, v: String) -> Result<Self::Value, E> {
+        Ok(v.into_value())
+    }
+
+    fn visit_bytes<E: Error>(self, v: &[u8]) -> Result<Self::Value, E> {
+        Ok(Bytes::from(v).into_value())
+    }
+
+    fn visit_borrowed_bytes<E: Error>(self, v: &'de [u8]) -> Result<Self::Value, E> {
+        Ok(Bytes::from(v).into_value())
+    }
+
+    fn visit_byte_buf<E: Error>(self, v: Vec<u8>) -> Result<Self::Value, E> {
+        Ok(Bytes::from(v).into_value())
+    }
+
+    fn visit_none<E: Error>(self) -> Result<Self::Value, E> {
+        Ok(Value::None)
+    }
+
+    fn visit_some<D: Deserializer<'de>>(
+        self,
+        deserializer: D,
+    ) -> Result<Self::Value, D::Error> {
+        Value::deserialize(deserializer)
+    }
+
+    fn visit_unit<E: Error>(self) -> Result<Self::Value, E> {
+        Ok(Value::None)
+    }
+
+    fn visit_seq<A: SeqAccess<'de>>(self, seq: A) -> Result<Self::Value, A::Error> {
+        Ok(Array::deserialize(SeqAccessDeserializer::new(seq))?.into_value())
+    }
+
+    fn visit_map<A: MapAccess<'de>>(self, map: A) -> Result<Self::Value, A::Error> {
+        let dict = Dict::deserialize(MapAccessDeserializer::new(map))?;
+        Ok(match parse_toml_date(&dict) {
+            None => dict.into_value(),
+            Some(dt) => Value::dynamic(dt),
+        })
+    }
+}
+
+impl<'de> Deserialize<'de> for Value {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_any(ValueVisitor)
+    }
+}
+
 /// A dynamic value.
 #[derive(Clone, Hash)]
 #[allow(clippy::derived_hash_with_manual_eq)]
diff --git a/tests/typ/compute/data.typ b/tests/typ/compute/data.typ
index 7b3fc576..d913d26e 100644
--- a/tests/typ/compute/data.typ
+++ b/tests/typ/compute/data.typ
@@ -60,6 +60,24 @@
   minute: 38,
   second: 57,
 ))
+#test(data.date_time2, datetime(
+  year: 2023,
+  month: 2,
+  day: 1,
+  hour: 15,
+  minute: 38,
+  second: 57,
+))
+#test(data.date, datetime(
+  year: 2023,
+  month: 2,
+  day: 1,
+))
+#test(data.time, datetime(
+  hour: 15,
+  minute: 38,
+  second: 57,
+))
 
 ---
 // Error: 7-24 failed to parse toml file: expected `.`, `=`, index 15-16
@@ -68,7 +86,7 @@
 ---
 // Test reading YAML data
 #let data = yaml("/files/yaml-types.yaml")
-#test(data.len(), 7)
+#test(data.len(), 8)
 #test(data.null_key, (none, none))
 #test(data.string, "text")
 #test(data.integer, 5)
@@ -76,7 +94,7 @@
 #test(data.mapping, ("1": "one", "2": "two"))
 #test(data.seq, (1,2,3,4))
 #test(data.bool, false)
-#test(data.keys().contains("true"), false)
+#test(data.keys().contains("true"), true)
 ---
 
 ---