Add optional support for the indexmap crate.

.github/workflows/rust.yml

@@ -22,14 +22,14 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: build
-          args: --workspace --all-targets --features json,toml,yaml --color=always
+          args: --workspace --all-targets --features indexmap,json,toml,yaml --color=always
       - name: Test
         uses: actions-rs/cargo@v1
         with:
           command: test
-          args: --workspace --all-targets --features json,toml,yaml --color=always
+          args: --workspace --all-targets --features indexmap,json,toml,yaml --color=always
       - name: Clippy
         uses: actions-rs/clippy-check@v1
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
-          args: --workspace --all-targets --features json,toml,yaml
+          args: --workspace --all-targets --features indexmap,json,toml,yaml

CHANGELOG

@@ -1,3 +1,6 @@
+# Unreleased
+- [add][minor] Add optional support for the `indexmap` crate.
+
 # Version 0.3.3 - 2024-06-29
 - [add][minor] Add support for substitution in all string values of TOML data.
 - [add][minor] Add support for substitution in all string values of JSON data.

Cargo.toml

@@ -14,6 +14,9 @@ categories = ["template-engine", "value-formatting"]
 edition = "2021"
 
 [features]
+# Implement `VariableMap` for `indexmap::IndexMap`.
+indexmap = ["dep:indexmap"]
+
 # Enable support for performing substitution in all string values of a JSON document.
 json = ["dep:serde", "dep:serde_json"]
 
@@ -30,6 +33,7 @@ preserve-order = ["toml?/preserve_order", "serde_json?/preserve_order"]
 doc-cfg = []
 
 [dependencies]
+indexmap = { version = "2.5.0", optional = true }
 memchr = "2.4.1"
 serde = { version = "1.0.0", optional = true }
 serde_json = { version = "1.0.118", optional = true }

src/features/indexmap.rs

@@ -0,0 +1,64 @@
+use indexmap::IndexMap;
+
+use crate::VariableMap;
+
+impl<'a, V: 'a> VariableMap<'a> for IndexMap<&str, V> {
+	type Value = &'a V;
+
+	#[inline]
+	fn get(&'a self, key: &str) -> Option<Self::Value> {
+		self.get(key)
+	}
+}
+
+impl<'a, V: 'a> VariableMap<'a> for IndexMap<String, V> {
+	type Value = &'a V;
+
+	#[inline]
+	fn get(&'a self, key: &str) -> Option<Self::Value> {
+		self.get(key)
+	}
+}
+
+#[cfg(test)]
+#[rustfmt::skip]
+mod test {
+	use indexmap::IndexMap;
+	use assert2::check;
+
+	use crate::{substitute, substitute_bytes};
+
+	#[test]
+	fn test_substitute() {
+		let mut map: IndexMap<String, String> = IndexMap::new();
+		map.insert("name".into(), "world".into());
+		check!(let Ok("Hello world!") = substitute("Hello $name!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${name}!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${name:not-world}!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${not_name:world}!", &map).as_deref());
+
+		let mut map: IndexMap<&str, &str> = IndexMap::new();
+		map.insert("name", "world");
+		check!(let Ok("Hello world!") = substitute("Hello $name!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${name}!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${name:not-world}!", &map).as_deref());
+		check!(let Ok("Hello world!") = substitute("Hello ${not_name:world}!", &map).as_deref());
+	}
+
+	#[test]
+	fn test_substitute_bytes() {
+		let mut map: IndexMap<String, Vec<u8>> = IndexMap::new();
+		map.insert("name".into(), b"world"[..].into());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello $name!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${name}!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${name:not-world}!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${not_name:world}!", &map).as_deref());
+
+		let mut map: IndexMap<&str, &[u8]> = IndexMap::new();
+		map.insert("name", b"world");
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello $name!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${name}!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${name:not-world}!", &map).as_deref());
+		check!(let Ok(b"Hello world!") = substitute_bytes(b"Hello ${not_name:world}!", &map).as_deref());
+	}
+}

src/features/mod.rs

@@ -1,3 +1,7 @@
+#[cfg(feature = "indexmap")]
+#[cfg_attr(feature = "doc-cfg", doc(cfg(feature = "indexmap")))]
+mod indexmap;
+
 #[cfg(feature = "json")]
 #[cfg_attr(feature = "doc-cfg", doc(cfg(feature = "json")))]
 pub mod json;