Repository: toml-rs/toml
Pull request #432 (2023-01-12 21:11:28)

feat(span): Split out serde_spanned
This will al.low `toml_edit` and `toml` to talk to each other.  I generalized this as other deserializers could use this.


Patch:
diff --git a/Cargo.lock b/Cargo.lock
index 54ad7a3b..5add1f0c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -786,6 +786,13 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_spanned"
+version = "0.5.0"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "similar"
 version = "2.2.0"
@@ -887,6 +894,7 @@ dependencies = [
  "serde",
  "serde_derive",
  "serde_json",
+ "serde_spanned",
  "toml_datetime",
 ]
 
diff --git a/crates/serde_spanned/CHANGELOG.md b/crates/serde_spanned/CHANGELOG.md
new file mode 100644
index 00000000..40293a79
--- /dev/null
+++ b/crates/serde_spanned/CHANGELOG.md
@@ -0,0 +1,11 @@
+# Changelog
+
+The format is based on [Keep a Changelog].
+
+[Keep a Changelog]: http://keepachangelog.com/en/1.0.0/
+
+<!-- next-header -->
+## [Unreleased] - ReleaseDate
+
+<!-- next-url -->
+[Unreleased]: https://github.com/toml-rs/toml/compare/205859ff8c88fcc351ca55abc08139a6785fd075...HEAD
diff --git a/crates/serde_spanned/Cargo.toml b/crates/serde_spanned/Cargo.toml
new file mode 100644
index 00000000..0b416cb4
--- /dev/null
+++ b/crates/serde_spanned/Cargo.toml
@@ -0,0 +1,38 @@
+[package]
+name = "serde_spanned"
+version = "0.5.0"
+readme = "README.md"
+license = "MIT OR Apache-2.0"
+keywords = ["serde", "span"]
+categories = ["encoding", "parser-implementations", "parsing", "config"]
+description = """
+A native Rust encoder and decoder of TOML-formatted files and streams. Provides
+implementations of the standard Serialize/Deserialize traits for TOML data to
+facilitate deserializing and serializing Rust structures.
+"""
+repository = "https://github.com/toml-rs/toml"
+homepage = "https://github.com/toml-rs/toml"
+documentation = "https://docs.rs/serde_spanned"
+edition = "2021"
+rust-version = "1.60.0"  # MSRV
+include = [
+  "src/**/*",
+  "Cargo.toml",
+  "LICENSE*",
+  "README.md",
+  "examples/**/*",
+  "benches/**/*",
+  "tests/**/*"
+]
+
+[package.metadata.release]
+pre-release-replacements = [
+  {file="CHANGELOG.md", search="Unreleased", replace="{{version}}", min=1},
+  {file="CHANGELOG.md", search="\\.\\.\\.HEAD", replace="...{{tag_name}}", exactly=1},
+  {file="CHANGELOG.md", search="ReleaseDate", replace="{{date}}", min=1},
+  {file="CHANGELOG.md", search="<!-- next-header -->", replace="<!-- next-header -->\n## [Unreleased] - ReleaseDate\n", exactly=1},
+  {file="CHANGELOG.md", search="<!-- next-url -->", replace="<!-- next-url -->\n[Unreleased]: https://github.com/toml-rs/toml/compare/{{tag_name}}...HEAD", exactly=1},
+]
+
+[dependencies]
+serde = { version = "1.0.145", optional = true }
diff --git a/crates/serde_spanned/LICENSE-APACHE b/crates/serde_spanned/LICENSE-APACHE
new file mode 100644
index 00000000..16fe87b0
--- /dev/null
+++ b/crates/serde_spanned/LICENSE-APACHE
@@ -0,0 +1,201 @@
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diff --git a/crates/serde_spanned/LICENSE-MIT b/crates/serde_spanned/LICENSE-MIT
new file mode 100644
index 00000000..39e0ed66
--- /dev/null
+++ b/crates/serde_spanned/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2014 Alex Crichton
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/crates/serde_spanned/README.md b/crates/serde_spanned/README.md
new file mode 100644
index 00000000..3923c31e
--- /dev/null
+++ b/crates/serde_spanned/README.md
@@ -0,0 +1,28 @@
+# serde_spanned
+
+[![Latest Version](https://img.shields.io/crates/v/serde_spanned.svg)](https://crates.io/crates/serde_spanned)
+[![Documentation](https://docs.rs/serde_spanned/badge.svg)](https://docs.rs/serde_spanned)
+
+A [serde]-compatible spanned Value
+
+This allows capturing the location, in bytes, for a value in the original parsed document for
+compatible deserializers.
+
+[serde]: https://serde.rs/
+
+# License
+
+This project is licensed under either of
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
+   http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or
+   http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in toml-rs by you, as defined in the Apache-2.0 license, shall be
+dual licensed as above, without any additional terms or conditions.
diff --git a/crates/serde_spanned/src/lib.rs b/crates/serde_spanned/src/lib.rs
new file mode 100644
index 00000000..88ffcb72
--- /dev/null
+++ b/crates/serde_spanned/src/lib.rs
@@ -0,0 +1,17 @@
+//! A [serde]-compatible spanned Value
+//!
+//! This allows capturing the location, in bytes, for a value in the original parsed document for
+//! compatible deserializers.
+//!
+//! [serde]: https://serde.rs/
+
+#![deny(missing_docs)]
+#![warn(rust_2018_idioms)]
+// Makes rustc abort compilation if there are any unsafe blocks in the crate.
+// Presence of this annotation is picked up by tools such as cargo-geiger
+// and lets them ensure that there is indeed no unsafe code as opposed to
+// something they couldn't detect (e.g. unsafe added via macro expansion, etc).
+#![forbid(unsafe_code)]
+
+mod spanned;
+pub use crate::spanned::*;
diff --git a/crates/serde_spanned/src/spanned.rs b/crates/serde_spanned/src/spanned.rs
new file mode 100644
index 00000000..db705959
--- /dev/null
+++ b/crates/serde_spanned/src/spanned.rs
@@ -0,0 +1,163 @@
+use std::cmp::Ordering;
+use std::hash::{Hash, Hasher};
+
+// Currently serde itself doesn't have a spanned type, so we map our `Spanned`
+// to a special value in the serde data model. Namely one with these special
+// fields/struct names.
+//
+// In general, supported deserializers should catch this and not literally emit
+// these strings but rather emit `Spanned` as they're intended.
+#[doc(hidden)]
+#[cfg(feature = "serde")]
+pub const NAME: &str = "$__serde_spanned_private_Spanned";
+#[doc(hidden)]
+#[cfg(feature = "serde")]
+pub const START_FIELD: &str = "$__serde_spanned_private_start";
+#[doc(hidden)]
+#[cfg(feature = "serde")]
+pub const END_FIELD: &str = "$__serde_spanned_private_end";
+#[doc(hidden)]
+#[cfg(feature = "serde")]
+pub const VALUE_FIELD: &str = "$__serde_spanned_private_value";
+
+/// A spanned value, indicating the range at which it is defined in the source.
+#[derive(Clone, Debug)]
+pub struct Spanned<T> {
+    /// Byte range
+    span: std::ops::Range<usize>,
+    /// The spanned value.
+    value: T,
+}
+
+impl<T> Spanned<T> {
+    /// Byte range
+    pub fn span(&self) -> std::ops::Range<usize> {
+        self.span.clone()
+    }
+
+    /// Consumes the spanned value and returns the contained value.
+    pub fn into_inner(self) -> T {
+        self.value
+    }
+
+    /// Returns a reference to the contained value.
+    pub fn get_ref(&self) -> &T {
+        &self.value
+    }
+
+    /// Returns a mutable reference to the contained value.
+    pub fn get_mut(&mut self) -> &mut T {
+        &mut self.value
+    }
+}
+
+impl std::borrow::Borrow<str> for Spanned<String> {
+    fn borrow(&self) -> &str {
+        self.get_ref()
+    }
+}
+
+impl<T> AsRef<T> for Spanned<T> {
+    fn as_ref(&self) -> &T {
+        self.get_ref()
+    }
+}
+
+impl<T> AsMut<T> for Spanned<T> {
+    fn as_mut(&mut self) -> &mut T {
+        self.get_mut()
+    }
+}
+
+impl<T: PartialEq> PartialEq for Spanned<T> {
+    fn eq(&self, other: &Self) -> bool {
+        self.value.eq(&other.value)
+    }
+}
+
+impl<T: Eq> Eq for Spanned<T> {}
+
+impl<T: Hash> Hash for Spanned<T> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.value.hash(state);
+    }
+}
+
+impl<T: PartialOrd> PartialOrd for Spanned<T> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        self.value.partial_cmp(&other.value)
+    }
+}
+
+impl<T: Ord> Ord for Spanned<T> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.value.cmp(&other.value)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl<'de, T> serde::de::Deserialize<'de> for Spanned<T>
+where
+    T: serde::de::Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Spanned<T>, D::Error>
+    where
+        D: serde::de::Deserializer<'de>,
+    {
+        struct SpannedVisitor<T>(::std::marker::PhantomData<T>);
+
+        impl<'de, T> serde::de::Visitor<'de> for SpannedVisitor<T>
+        where
+            T: serde::de::Deserialize<'de>,
+        {
+            type Value = Spanned<T>;
+
+            fn expecting(&self, formatter: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                formatter.write_str("a spanned value")
+            }
+
+            fn visit_map<V>(self, mut visitor: V) -> Result<Spanned<T>, V::Error>
+            where
+                V: serde::de::MapAccess<'de>,
+            {
+                if visitor.next_key()? != Some(START_FIELD) {
+                    return Err(serde::de::Error::custom("spanned start key not found"));
+                }
+
+                let start: usize = visitor.next_value()?;
+
+                if visitor.next_key()? != Some(END_FIELD) {
+                    return Err(serde::de::Error::custom("spanned end key not found"));
+                }
+
+                let end: usize = visitor.next_value()?;
+
+                if visitor.next_key()? != Some(VALUE_FIELD) {
+                    return Err(serde::de::Error::custom("spanned value key not found"));
+                }
+
+                let value: T = visitor.next_value()?;
+
+                Ok(Spanned {
+                    span: start..end,
+                    value,
+                })
+            }
+        }
+
+        let visitor = SpannedVisitor(::std::marker::PhantomData);
+
+        static FIELDS: [&str; 3] = [START_FIELD, END_FIELD, VALUE_FIELD];
+        deserializer.deserialize_struct(NAME, &FIELDS, visitor)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl<T: serde::ser::Serialize> serde::ser::Serialize for Spanned<T> {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::ser::Serializer,
+    {
+        self.value.serialize(serializer)
+    }
+}
diff --git a/crates/toml/Cargo.toml b/crates/toml/Cargo.toml
index 43902721..636dba42 100644
--- a/crates/toml/Cargo.toml
+++ b/crates/toml/Cargo.toml
@@ -47,6 +47,7 @@ preserve_order = ["indexmap"]
 serde = "1.0.145"
 indexmap = { version = "1.9.1", optional = true }
 toml_datetime = { version = "0.5.0", path = "../toml_datetime", features = ["serde"] }
+serde_spanned = { version = "0.5.0", path = "../serde_spanned", features = ["serde"] }
 
 [dev-dependencies]
 serde_derive = "1.0.152"
diff --git a/crates/toml/src/de.rs b/crates/toml/src/de.rs
index f00730bf..cda0ca38 100644
--- a/crates/toml/src/de.rs
+++ b/crates/toml/src/de.rs
@@ -19,7 +19,6 @@ use serde::de::value::BorrowedStrDeserializer;
 use serde::de::IntoDeserializer;
 use toml_datetime::__unstable as datetime;
 
-use crate::spanned;
 use crate::tokens::{Error as TokenError, Span, Token, Tokenizer};
 
 /// Type Alias for a TOML Table pair
@@ -295,7 +294,14 @@ impl<'de, 'b> de::Deserializer<'de> for &'b mut Deserializer<'de> {
     where
         V: de::Visitor<'de>,
     {
-        if name == spanned::NAME && fields == [spanned::START, spanned::END, spanned::VALUE] {
+        if name == serde_spanned::NAME
+            && fields
+                == [
+                    serde_spanned::START_FIELD,
+                    serde_spanned::END_FIELD,
+                    serde_spanned::VALUE_FIELD,
+                ]
+        {
             let start = 0;
             let end = self.input.len();
 
@@ -638,8 +644,13 @@ impl<'de, 'b> de::Deserializer<'de> for MapVisitor<'de, 'b> {
     where
         V: de::Visitor<'de>,
     {
-        if name == spanned::NAME
-            && fields == [spanned::START, spanned::END, spanned::VALUE]
+        if name == serde_spanned::NAME
+            && fields
+                == [
+                    serde_spanned::START_FIELD,
+                    serde_spanned::END_FIELD,
+                    serde_spanned::VALUE_FIELD,
+                ]
             && !(self.array && self.values.peek().is_some())
         {
             // TODO we can't actually emit spans here for the *entire* table/array
@@ -747,7 +758,14 @@ impl<'de> de::Deserializer<'de> for StrDeserializer<'de> {
     where
         V: de::Visitor<'de>,
     {
-        if name == spanned::NAME && fields == [spanned::START, spanned::END, spanned::VALUE] {
+        if name == serde_spanned::NAME
+            && fields
+                == [
+                    serde_spanned::START_FIELD,
+                    serde_spanned::END_FIELD,
+                    serde_spanned::VALUE_FIELD,
+                ]
+        {
             if let Some(span) = self.span {
                 return visitor.visit_map(SpannedDeserializer {
                     phantom_data: PhantomData,
@@ -874,7 +892,14 @@ impl<'de> de::Deserializer<'de> for ValueDeserializer<'de> {
             }
         }
 
-        if name == spanned::NAME && fields == [spanned::START, spanned::END, spanned::VALUE] {
+        if name == serde_spanned::NAME
+            && fields
+                == [
+                    serde_spanned::START_FIELD,
+                    serde_spanned::END_FIELD,
+                    serde_spanned::VALUE_FIELD,
+                ]
+        {
             let start = self.value.start;
             let end = self.value.end;
 
@@ -999,13 +1024,13 @@ where
         K: de::DeserializeSeed<'de>,
     {
         if self.start.is_some() {
-            seed.deserialize(BorrowedStrDeserializer::new(spanned::START))
+            seed.deserialize(BorrowedStrDeserializer::new(serde_spanned::START_FIELD))
                 .map(Some)
         } else if self.end.is_some() {
-            seed.deserialize(BorrowedStrDeserializer::new(spanned::END))
+            seed.deserialize(BorrowedStrDeserializer::new(serde_spanned::END_FIELD))
                 .map(Some)
         } else if self.value.is_some() {
-            seed.deserialize(BorrowedStrDeserializer::new(spanned::VALUE))
+            seed.deserialize(BorrowedStrDeserializer::new(serde_spanned::VALUE_FIELD))
                 .map(Some)
         } else {
             Ok(None)
diff --git a/crates/toml/src/lib.rs b/crates/toml/src/lib.rs
index eb700200..bf65968c 100644
--- a/crates/toml/src/lib.rs
+++ b/crates/toml/src/lib.rs
@@ -161,8 +161,7 @@ mod tokens;
 #[doc(hidden)]
 pub mod macros;
 
-mod spanned;
-pub use crate::spanned::Spanned;
+pub use serde_spanned::Spanned;
 
 // Shortcuts for the module doc-comment
 #[allow(unused_imports)]
diff --git a/crates/toml/src/spanned.rs b/crates/toml/src/spanned.rs
deleted file mode 100644
index f90c5492..00000000
--- a/crates/toml/src/spanned.rs
+++ /dev/null
@@ -1,166 +0,0 @@
-use serde::{de, ser};
-use std::borrow::Borrow;
-use std::cmp::Ordering;
-use std::fmt;
-use std::hash::{Hash, Hasher};
-
-pub(crate) const NAME: &str = "$__toml_private_Spanned";
-pub(crate) const START: &str = "$__toml_private_start";
-pub(crate) const END: &str = "$__toml_private_end";
-pub(crate) const VALUE: &str = "$__toml_private_value";
-
-/// A spanned value, indicating the range at which it is defined in the source.
-///
-/// ```
-/// use serde_derive::Deserialize;
-/// use toml::Spanned;
-///
-/// #[derive(Deserialize)]
-/// struct Value {
-///     s: Spanned<String>,
-/// }
-///
-/// let t = "s = \"value\"\n";
-///
-/// let u: Value = toml::from_str(t).unwrap();
-///
-/// assert_eq!(u.s.start(), 4);
-/// assert_eq!(u.s.end(), 11);
-/// assert_eq!(u.s.get_ref(), "value");
-/// assert_eq!(u.s.into_inner(), String::from("value"));
-/// ```
-#[derive(Clone, Debug)]
-pub struct Spanned<T> {
-    /// The start range.
-    start: usize,
-    /// The end range (exclusive).
-    end: usize,
-    /// The spanned value.
-    value: T,
-}
-
-impl<T> Spanned<T> {
-    /// Access the start of the span of the contained value.
-    pub fn start(&self) -> usize {
-        self.start
-    }
-
-    /// Access the end of the span of the contained value.
-    pub fn end(&self) -> usize {
-        self.end
-    }
-
-    /// Get the span of the contained value.
-    pub fn span(&self) -> (usize, usize) {
-        (self.start, self.end)
-    }
-
-    /// Consumes the spanned value and returns the contained value.
-    pub fn into_inner(self) -> T {
-        self.value
-    }
-
-    /// Returns a reference to the contained value.
-    pub fn get_ref(&self) -> &T {
-        &self.value
-    }
-
-    /// Returns a mutable reference to the contained value.
-    pub fn get_mut(&mut self) -> &mut T {
-        &mut self.value
-    }
-}
-
-impl Borrow<str> for Spanned<String> {
-    fn borrow(&self) -> &str {
-        self.get_ref()
-    }
-}
-
-impl<T: PartialEq> PartialEq for Spanned<T> {
-    fn eq(&self, other: &Self) -> bool {
-        self.value.eq(&other.value)
-    }
-}
-
-impl<T: Eq> Eq for Spanned<T> {}
-
-impl<T: Hash> Hash for Spanned<T> {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        self.value.hash(state);
-    }
-}
-
-impl<T: PartialOrd> PartialOrd for Spanned<T> {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        self.value.partial_cmp(&other.value)
-    }
-}
-
-impl<T: Ord> Ord for Spanned<T> {
-    fn cmp(&self, other: &Self) -> Ordering {
-        self.value.cmp(&other.value)
-    }
-}
-
-impl<'de, T> de::Deserialize<'de> for Spanned<T>
-where
-    T: de::Deserialize<'de>,
-{
-    fn deserialize<D>(deserializer: D) -> Result<Spanned<T>, D::Error>
-    where
-        D: de::Deserializer<'de>,
-    {
-        struct SpannedVisitor<T>(::std::marker::PhantomData<T>);
-
-        impl<'de, T> de::Visitor<'de> for SpannedVisitor<T>
-        where
-            T: de::Deserialize<'de>,
-        {
-            type Value = Spanned<T>;
-
-            fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
-                formatter.write_str("a TOML spanned")
-            }
-
-            fn visit_map<V>(self, mut visitor: V) -> Result<Spanned<T>, V::Error>
-            where
-                V: de::MapAccess<'de>,
-            {
-                if visitor.next_key()? != Some(START) {
-                    return Err(de::Error::custom("spanned start key not found"));
-                }
-
-                let start: usize = visitor.next_value()?;
-
-                if visitor.next_key()? != Some(END) {
-                    return Err(de::Error::custom("spanned end key not found"));
-                }
-
-                let end: usize = visitor.next_value()?;
-
-                if visitor.next_key()? != Some(VALUE) {
-                    return Err(de::Error::custom("spanned value key not found"));
-                }
-
-                let value: T = visitor.next_value()?;
-
-                Ok(Spanned { start, end, value })
-            }
-        }
-
-        let visitor = SpannedVisitor(::std::marker::PhantomData);
-
-        static FIELDS: [&str; 3] = [START, END, VALUE];
-        deserializer.deserialize_struct(NAME, &FIELDS, visitor)
-    }
-}
-
-impl<T: ser::Serialize> ser::Serialize for Spanned<T> {
-    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: ser::Serializer,
-    {
-        self.value.serialize(serializer)
-    }
-}
diff --git a/crates/toml_datetime/src/datetime.rs b/crates/toml_datetime/src/datetime.rs
index 8aebc5b4..d468c420 100644
--- a/crates/toml_datetime/src/datetime.rs
+++ b/crates/toml_datetime/src/datetime.rs
@@ -99,7 +99,7 @@ pub struct DatetimeParseError {
 }
 
 // Currently serde itself doesn't have a datetime type, so we map our `Datetime`
-// to a special valid in the serde data model. Namely one with these special
+// to a special value in the serde data model. Namely one with these special
 // fields/struct names.
 //
 // In general the TOML encoder/decoder will catch this and not literally emit


Test patch:
diff --git a/crates/test-suite/tests/spanned.rs b/crates/test-suite/tests/spanned.rs
index ea1e8c86..710f5d95 100644
--- a/crates/test-suite/tests/spanned.rs
+++ b/crates/test-suite/tests/spanned.rs
@@ -40,19 +40,19 @@ fn test_spanned_field() {
     {
         let foo: Foo<T> = toml::from_str(s).unwrap();
 
-        assert_eq!(6, foo.foo.start());
+        assert_eq!(6, foo.foo.span().start);
         if let Some(end) = end {
-            assert_eq!(end, foo.foo.end());
+            assert_eq!(end, foo.foo.span().end);
         } else {
-            assert_eq!(s.len(), foo.foo.end());
+            assert_eq!(s.len(), foo.foo.span().end);
         }
-        assert_eq!(expected, &s[foo.foo.start()..foo.foo.end()]);
+        assert_eq!(expected, &s[foo.foo.span()]);
 
         // Test for Spanned<> at the top level
         let foo_outer: Spanned<BareFoo<T>> = toml::from_str(s).unwrap();
 
-        assert_eq!(0, foo_outer.start());
-        assert_eq!(s.len(), foo_outer.end());
+        assert_eq!(0, foo_outer.span().start);
+        assert_eq!(s.len(), foo_outer.span().end);
         assert_eq!(foo.foo.into_inner(), foo_outer.into_inner().foo);
     }
 
@@ -94,21 +94,21 @@ fn test_inner_spanned_table() {
         let foo: Foo = toml::from_str(s).unwrap();
 
         if zero {
-            assert_eq!(foo.foo.start(), 0);
+            assert_eq!(foo.foo.span().start, 0);
             // We'd actually have to assert equality with s.len() here,
             // but the current implementation doesn't support that,
             // and it's not possible with toml's data format to support it
             // in the general case as spans aren't always well-defined.
             // So this check mainly serves as a reminder that this test should
             // be updated *if* one day there is support for emitting the actual span.
-            assert_eq!(foo.foo.end(), 0);
+            assert_eq!(foo.foo.span().end, 0);
         } else {
-            assert_eq!(foo.foo.start(), s.find('{').unwrap());
-            assert_eq!(foo.foo.end(), s.find('}').unwrap() + 1);
+            assert_eq!(foo.foo.span().start, s.find('{').unwrap());
+            assert_eq!(foo.foo.span().end, s.find('}').unwrap() + 1);
         }
-        for (k, v) in foo.foo.get_ref().iter() {
-            assert_eq!(&s[k.start()..k.end()], k.get_ref());
-            assert_eq!(&s[(v.start() + 1)..(v.end() - 1)], v.get_ref());
+        for (k, v) in foo.foo.as_ref().iter() {
+            assert_eq!(&s[k.span().start..k.span().end], k.as_ref());
+            assert_eq!(&s[(v.span().start + 1)..(v.span().end - 1)], v.as_ref());
         }
     }
 
@@ -141,8 +141,8 @@ fn test_outer_spanned_table() {
         let foo: Foo = toml::from_str(s).unwrap();
 
         for (k, v) in foo.foo.iter() {
-            assert_eq!(&s[k.start()..k.end()], k.get_ref());
-            assert_eq!(&s[(v.start() + 1)..(v.end() - 1)], v.get_ref());
+            assert_eq!(&s[k.span().start..k.span().end], k.as_ref());
+            assert_eq!(&s[(v.span().start + 1)..(v.span().end - 1)], v.as_ref());
         }
     }
 
@@ -174,10 +174,13 @@ fn test_spanned_nested() {
         let foo: Foo = toml::from_str(s).unwrap();
 
         for (k, v) in foo.foo.iter() {
-            assert_eq!(&s[k.start()..k.end()], k.get_ref());
+            assert_eq!(&s[k.span().start..k.span().end], k.as_ref());
             for (n_k, n_v) in v.iter() {
-                assert_eq!(&s[n_k.start()..n_k.end()], n_k.get_ref());
-                assert_eq!(&s[(n_v.start() + 1)..(n_v.end() - 1)], n_v.get_ref());
+                assert_eq!(&s[n_k.span().start..n_k.span().end], n_k.as_ref());
+                assert_eq!(
+                    &s[(n_v.span().start + 1)..(n_v.span().end - 1)],
+                    n_v.as_ref()
+                );
             }
         }
     }
@@ -214,17 +217,17 @@ fn test_spanned_array() {
         let foo_list: Foo = toml::from_str(s).unwrap();
 
         for foo in foo_list.foo.iter() {
-            assert_eq!(foo.start(), 0);
+            assert_eq!(foo.span().start, 0);
             // We'd actually have to assert equality with s.len() here,
             // but the current implementation doesn't support that,
             // and it's not possible with toml's data format to support it
             // in the general case as spans aren't always well-defined.
             // So this check mainly serves as a reminder that this test should
             // be updated *if* one day there is support for emitting the actual span.
-            assert_eq!(foo.end(), 0);
-            for (k, v) in foo.get_ref().iter() {
-                assert_eq!(&s[k.start()..k.end()], k.get_ref());
-                assert_eq!(&s[(v.start() + 1)..(v.end() - 1)], v.get_ref());
+            assert_eq!(foo.span().end, 0);
+            for (k, v) in foo.as_ref().iter() {
+                assert_eq!(&s[k.span().start..k.span().end], k.as_ref());
+                assert_eq!(&s[(v.span().start + 1)..(v.span().end - 1)], v.as_ref());
             }
         }
     }