Reorganize API and internals of serde_dhall a bit

12 files changed, 152 insertions, 76 deletions

diff --git a/Cargo.lock b/Cargo.lock
index f5cb0cc..e5a25e4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -14,7 +14,7 @@ version = "0.2.0"
 dependencies = [
  "abnf 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "itertools 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "pretty 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
diff --git a/README.md b/README.md
index 8afcac6..efe4c91 100644
--- a/README.md
+++ b/README.md
@@ -170,7 +170,7 @@ same name as the corresponding test.
 #### [???]
 
 - Add `serde_dhall::options` for finer control over Dhall behavior
-- Breaking change: use `serde_dhall::simple::Type` type for type-checking instead of `serde_dhall::Value`
+- Breaking change: reworked most of the `serde_dhall` api
 
 #### [0.4.0]
 
diff --git a/abnf_to_pest/Cargo.toml b/abnf_to_pest/Cargo.toml
index 780010e..1567512 100644
--- a/abnf_to_pest/Cargo.toml
+++ b/abnf_to_pest/Cargo.toml
@@ -14,5 +14,5 @@ doctest = false
 [dependencies]
 abnf = "0.6.0"
 indexmap = "1.0.2"
-itertools = "0.8.0"
+itertools = "0.9.0"
 pretty = "0.5.2"
diff --git a/dhall/src/semantics/resolve/resolve.rs b/dhall/src/semantics/resolve/resolve.rs
index fe3f3a9..7745e0b 100644
--- a/dhall/src/semantics/resolve/resolve.rs
+++ b/dhall/src/semantics/resolve/resolve.rs
@@ -341,7 +341,7 @@ pub fn skip_resolve_expr(expr: &Expr) -> Result<Hir, Error> {
 
 pub fn skip_resolve(parsed: Parsed) -> Result<Resolved, Error> {
     let Parsed(expr, _) = parsed;
-    let resolved =skip_resolve_expr(&expr)?;
+    let resolved = skip_resolve_expr(&expr)?;
     Ok(Resolved(resolved))
 }
 
diff --git a/serde_dhall/src/serde.rs b/serde_dhall/src/deserialize.rs
index 717450a..75a08a9 100644
--- a/serde_dhall/src/serde.rs
+++ b/serde_dhall/src/deserialize.rs
@@ -1,15 +1,28 @@
-use std::borrow::Cow;
-
 use serde::de::value::{
     MapAccessDeserializer, MapDeserializer, SeqDeserializer,
 };
+use std::borrow::Cow;
 
 use dhall::syntax::NumKind;
 
 use crate::simple::{ValKind, Value as SimpleValue};
-use crate::{Deserialize, Error, Result, Value};
+use crate::{Error, Result, Value};
+
+pub trait Sealed {}
+
+/// A data structure that can be deserialized from a Dhall expression
+///
+/// This is automatically implemented for any type that [serde][serde]
+/// can deserialize.
+///
+/// This trait cannot be implemented manually.
+pub trait Deserialize: Sealed + Sized {
+    #[doc(hidden)]
+    /// See [serde_dhall::from_str][crate::from_str]
+    fn from_dhall(v: &Value) -> Result<Self>;
+}
 
-impl<'a, T> crate::sealed::Sealed for T where T: serde::Deserialize<'a> {}
+impl<'a, T> Sealed for T where T: serde::Deserialize<'a> {}
 
 struct Deserializer<'a>(Cow<'a, SimpleValue>);
 
diff --git a/serde_dhall/src/lib.rs b/serde_dhall/src/lib.rs
index 4250882..5ee1cf6 100644
--- a/serde_dhall/src/lib.rs
+++ b/serde_dhall/src/lib.rs
@@ -1,4 +1,6 @@
 #![doc(html_root_url = "https://docs.rs/serde_dhall/0.4.0")]
+// #![warn(missing_docs)]
+// #![warn(missing_doc_code_examples)]
 //! [Dhall][dhall] is a programmable configuration language that provides a non-repetitive
 //! alternative to JSON and YAML.
 //!
@@ -107,7 +109,7 @@
 //! can let Rust infer it for you.
 //!
 //! To provide a type written in Dhall, first parse it into a [`simple::Type`](simple/struct.Type.html), then
-//! pass it to [`from_str_check_type`](fn.from_str_check_type.html).
+//! pass it to [`from_str_manual_type`](fn.from_str_manual_type.html).
 //!
 //! ```rust
 //! # fn main() -> serde_dhall::Result<()> {
@@ -124,7 +126,7 @@
 //! // Deserialize the data to a Rust type. This checks that
 //! // the data matches the provided type.
 //! let deserialized_map: HashMap<String, usize> =
-//!         serde_dhall::from_str_check_type(point_data, &point_type)?;
+//!         serde_dhall::from_str_manual_type(point_data, &point_type)?;
 //!
 //! let mut expected_map = HashMap::new();
 //! expected_map.insert("x".to_string(), 1);
@@ -153,13 +155,13 @@
 //! let data = "{ x = 1, y = 1 + 1 }";
 //!
 //! // Convert the Dhall string to a Point.
-//! let point: Point = serde_dhall::from_str_auto_type(data)?;
+//! let point: Point = serde_dhall::from_str_static_type(data)?;
 //! assert_eq!(point.x, 1);
 //! assert_eq!(point.y, 2);
 //!
 //! // Invalid data fails the type validation
 //! let invalid_data = "{ x = 1, z = 0.3 }";
-//! assert!(serde_dhall::from_str_auto_type::<Point>(invalid_data).is_err());
+//! assert!(serde_dhall::from_str_static_type::<Point>(invalid_data).is_err());
 //! # Ok(())
 //! # }
 //! ```
@@ -171,72 +173,26 @@
 #[cfg(doctest)]
 doc_comment::doctest!("../../README.md");
 
-mod error;
 /// Finer-grained control over deserializing Dhall
 pub mod options;
-mod serde;
-/// Serde-compatible values and their type
+/// Serde-compatible Dhall values and their type
 pub mod simple;
-mod static_type;
 /// Arbitrary Dhall values
 pub mod value;
 
-pub use crate::simple::{Type as SimpleType, Value as SimpleValue};
+mod deserialize;
+mod error;
+/// Common patterns made easier
+mod shortcuts;
+mod static_type;
+
 #[doc(hidden)]
 pub use dhall_proc_macros::StaticType;
+
+pub use deserialize::Deserialize;
+pub(crate) use deserialize::Sealed;
 pub use error::{Error, Result};
+pub use shortcuts::{from_str, from_str_manual_type, from_str_static_type};
+pub use simple::{Type as SimpleType, Value as SimpleValue};
 pub use static_type::StaticType;
 pub use value::Value;
-
-pub(crate) mod sealed {
-    pub trait Sealed {}
-}
-
-/// A data structure that can be deserialized from a Dhall expression
-///
-/// This is automatically implemented for any type that [serde][serde]
-/// can deserialize.
-///
-/// This trait cannot be implemented manually.
-pub trait Deserialize: sealed::Sealed + Sized {
-    /// See [serde_dhall::from_str][crate::from_str]
-    fn from_dhall(v: &Value) -> Result<Self>;
-}
-
-/// Deserialize an instance of type `T` from a string of Dhall text.
-///
-/// This will recursively resolve all imports in the expression, and
-/// typecheck it before deserialization. Relative imports will be resolved relative to the
-/// provided file. More control over this process is not yet available
-/// but will be in a coming version of this crate.
-pub fn from_str<T>(s: &str) -> Result<T>
-where
-    T: Deserialize,
-{
-    options::from_str(s).parse()
-}
-
-/// Deserialize an instance of type `T` from a string of Dhall text,
-/// additionally checking that it matches the supplied type.
-///
-/// Like [from_str], but this additionally checks that
-/// the type of the provided expression matches the supplied type.
-pub fn from_str_check_type<T>(s: &str, ty: &simple::Type) -> Result<T>
-where
-    T: Deserialize,
-{
-    options::from_str(s).type_annotation(ty).parse()
-}
-
-/// Deserialize an instance of type `T` from a string of Dhall text,
-/// additionally checking that it matches the type of `T`.
-///
-/// Like [from_str], but this additionally checks that
-/// the type of the provided expression matches the output type `T`. The [StaticType] trait
-/// captures Rust types that are valid Dhall types.
-pub fn from_str_auto_type<T>(s: &str) -> Result<T>
-where
-    T: Deserialize + StaticType,
-{
-    options::from_str(s).static_type_annotation().parse()
-}
diff --git a/serde_dhall/src/shortcuts.rs b/serde_dhall/src/shortcuts.rs
new file mode 100644
index 0000000..1fb1032
--- /dev/null
+++ b/serde_dhall/src/shortcuts.rs
@@ -0,0 +1,100 @@
+use crate::error::Result;
+use crate::options;
+use crate::simple::Type as SimpleType;
+use crate::static_type::StaticType;
+use crate::Deserialize;
+
+/// Deserialize an instance of type `T` from a string of Dhall text.
+///
+/// This will recursively resolve all imports in the expression, and typecheck it before
+/// deserialization. Relative imports will be resolved relative to the current directory.
+/// See [`options`][`options`] for more control over this process.
+///
+/// For additional type safety, prefer [`from_str_static_type`][`from_str_static_type`] or
+/// [`from_str_manual_type`][`from_str_manual_type`].
+///
+///
+/// # Example
+///
+/// ```rust
+/// # fn main() -> serde_dhall::Result<()> {
+/// use serde::Deserialize;
+///
+/// #[derive(Debug, Deserialize)]
+/// struct Point {
+///     x: u64,
+///     y: u64,
+/// }
+///
+/// // Some Dhall data
+/// let data = "{ x = 1, y = 1 + 1 } : { x: Natural, y: Natural }";
+///
+/// // Convert the Dhall string to a Point.
+/// let point: Point = serde_dhall::from_str(data)?;
+/// assert_eq!(point.x, 1);
+/// assert_eq!(point.y, 2);
+///
+/// # Ok(())
+/// # }
+/// ```
+///
+/// [`options`]: options/index.html
+/// [`from_str_manual_type`]: fn.from_str_manual_type.html
+/// [`from_str_static_type`]: fn.from_str_static_type.html
+pub fn from_str<T>(s: &str) -> Result<T>
+where
+    T: Deserialize,
+{
+    options::from_str(s).parse()
+}
+
+/// Deserialize an instance of type `T` from a string of Dhall text,
+/// additionally checking that it matches the supplied type.
+///
+/// Like [`from_str`], but this additionally checks that
+/// the type of the provided expression matches the supplied type.
+///
+/// ```rust
+/// # fn main() -> serde_dhall::Result<()> {
+/// use serde_dhall::simple::Type;
+/// use std::collections::HashMap;
+///
+/// // Parse a Dhall type
+/// let point_type_str = "{ x: Natural, y: Natural }";
+/// let point_type: Type = serde_dhall::from_str(point_type_str)?;
+///
+/// // Some Dhall data
+/// let point_data = "{ x = 1, y = 1 + 1 }";
+///
+/// // Deserialize the data to a Rust type. This checks that
+/// // the data matches the provided type.
+/// let deserialized_map: HashMap<String, usize> =
+///         serde_dhall::from_str_manual_type(point_data, &point_type)?;
+///
+/// let mut expected_map = HashMap::new();
+/// expected_map.insert("x".to_string(), 1);
+/// expected_map.insert("y".to_string(), 2);
+///
+/// assert_eq!(deserialized_map, expected_map);
+/// # Ok(())
+/// # }
+/// ```
+pub fn from_str_manual_type<T>(s: &str, ty: &SimpleType) -> Result<T>
+where
+    T: Deserialize,
+{
+    options::from_str(s).type_annotation(ty).parse()
+}
+
+/// Deserialize an instance of type `T` from a string of Dhall text,
+/// additionally checking that it matches the type of `T`.
+///
+/// Like [from_str], but this additionally checks that
+/// the type of the provided expression matches the output type `T`. The [StaticType] trait
+/// captures Rust types that are valid Dhall types.
+pub fn from_str_static_type<T>(s: &str) -> Result<T>
+where
+    T: Deserialize + StaticType,
+{
+    options::from_str(s).static_type_annotation().parse()
+}
diff --git a/serde_dhall/src/simple.rs b/serde_dhall/src/simple.rs
index 4cd4ab7..95642bd 100644
--- a/serde_dhall/src/simple.rs
+++ b/serde_dhall/src/simple.rs
@@ -3,7 +3,7 @@ use std::collections::BTreeMap;
 use dhall::semantics::{Hir, HirKind, Nir, NirKind};
 use dhall::syntax::{Builtin, ExprKind, NumKind, Span};
 
-use crate::{sealed::Sealed, Deserialize, Error, Result};
+use crate::{Deserialize, Error, Result, Sealed};
 
 /// A simple value of the kind that can be encoded/decoded with serde
 #[derive(Debug, Clone, PartialEq, Eq)]
diff --git a/serde_dhall/src/value.rs b/serde_dhall/src/value.rs
index d4ded90..a119028 100644
--- a/serde_dhall/src/value.rs
+++ b/serde_dhall/src/value.rs
@@ -2,7 +2,7 @@ use dhall::semantics::{Hir, Nir};
 use dhall::syntax::Expr;
 
 use crate::simple::{Type as SimpleType, Value as SimpleValue};
-use crate::{sealed::Sealed, Deserialize, Error};
+use crate::{Deserialize, Error, Sealed};
 
 /// An arbitrary Dhall value.
 #[derive(Debug, Clone)]
diff --git a/serde_dhall/tests/de.rs b/serde_dhall/tests/de.rs
index b201e4f..f28b265 100644
--- a/serde_dhall/tests/de.rs
+++ b/serde_dhall/tests/de.rs
@@ -1,10 +1,10 @@
 use serde::Deserialize;
-use serde_dhall::{from_str, from_str_auto_type, StaticType};
+use serde_dhall::{from_str, from_str_static_type, StaticType};
 
 #[test]
 fn test_de_typed() {
     fn parse<T: serde_dhall::Deserialize + StaticType>(s: &str) -> T {
-        from_str_auto_type(s).unwrap()
+        from_str_static_type(s).unwrap()
     }
 
     assert_eq!(parse::<bool>("True"), true);
@@ -52,7 +52,7 @@ fn test_de_typed() {
     }
     assert_eq!(parse::<Baz>("< X | Y: Integer >.X"), Baz::X);
 
-    assert!(from_str_auto_type::<Baz>("< X | Y: Integer >.Y").is_err());
+    assert!(from_str_static_type::<Baz>("< X | Y: Integer >.Y").is_err());
 }
 
 #[test]
diff --git a/serde_dhall/tests/version_numbers.rs b/serde_dhall/tests/version_numbers.rs
index 97254a9..8307e47 100644
--- a/serde_dhall/tests/version_numbers.rs
+++ b/serde_dhall/tests/version_numbers.rs
@@ -10,5 +10,8 @@ fn test_html_root_url() {
 
 #[test]
 fn test_readme_mentions_version() {
-    version_sync::assert_contains_regex!("../README.md", "^#### \\[{version}\\]");
+    version_sync::assert_contains_regex!(
+        "../README.md",
+        "^#### \\[{version}\\]"
+    );
 }
diff --git a/tests_buffer b/tests_buffer
index 74e76bc..d07ddbd 100644
--- a/tests_buffer
+++ b/tests_buffer
@@ -7,6 +7,10 @@ x.({ a : Bool, b })
 x.({ a })
 x.{ a : Bool }
 s/QuotedVariable/VariableQuoted/
+From https://github.com/dhall-lang/dhall-lang/issues/280 :
+    "${ not_really_an_expression ;-) }"
+    ''${ not_an_expression ;-) }''
+    {- {- -} 1
 
 import:
 failure/