Merge pull request #51 from corn-config/fix/serde-numeric-keys

JakeStanger · web-flow · commit 095fbada141e · 2026-01-23T23:25:07.000Z
Fix serde numeric keys
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -49,32 +49,29 @@ indexmap = { version = "2.7.1", features = ["serde"] }
 # Error handling
 thiserror = "2.0.12"
 
-# Utilities
-cfg-if = "1.0.0"
-
 # WASM support (optional)
 wasm-bindgen = { version = "0.2.100", optional = true }
 serde-wasm-bindgen = { version = "0.6.5", optional = true }
 console_error_panic_hook = { version = "0.1.7", optional = true }
 wee_alloc = { version = "0.4.5", optional = true }
 
 # Lua support (optional)
-mlua = { version = "0.10.3", features = [
+mlua = { version = "0.11.5", features = [
     "module",
     "macros",
     "serialize",
 ], optional = true }
 
 # Benchmarking (optional)
-criterion = { version = "0.5.1", features = ["html_reports"], optional = true }
+criterion = { version = "0.8.1", features = ["html_reports"], optional = true }
 
 [dev-dependencies]
 paste = "1.0.15"
 wasm-bindgen-test = { version = "0.3.50" }
 serde_json = "1.0.140"
 serde_norway = "0.9.42"
 serde_bytes = "0.11.16"
-toml_edit = { version = "0.22.24", features = ["serde"] }
+toml_edit = { version = "0.24.0", features = ["serde"] }
 
 [profile.release]
 lto = true
diff --git a/assets/inputs/numeric_keys.corn b/assets/inputs/numeric_keys.corn
@@ -0,0 +1,3 @@
+{
+    foo = { 0 = "low" 33 = "medium" 67 = "high" }
+}
diff --git a/assets/outputs/json/numeric_keys.json b/assets/outputs/json/numeric_keys.json
@@ -0,0 +1,7 @@
+{
+  "foo": {
+    "0": "low",
+    "33": "medium",
+    "67": "high"
+  }
+}
diff --git a/assets/outputs/toml/numeric_keys.toml b/assets/outputs/toml/numeric_keys.toml
@@ -0,0 +1,4 @@
+[foo]
+0 = "low"
+33 = "medium"
+67 = "high"
diff --git a/assets/outputs/yaml/numeric_keys.yml b/assets/outputs/yaml/numeric_keys.yml
@@ -0,0 +1,5 @@
+foo:
+  0: low
+  33: medium
+  67: high
+
diff --git a/cli/Cargo.toml b/cli/Cargo.toml
@@ -7,7 +7,7 @@ description = "CLI for Corn. A simple and pain-free configuration language."
 repository = "https://github.com/corn-config/corn"
 categories = ["config", "command-line-utilities"]
 keywords = ["configuration", "language", "pest", "peg", "cli"]
-authors = ["Jake Stanger <mail@jakestanger.com>"]
+authors = ["Jake Stanger <mail@jstanger.dev>"]
 readme = "README.md"
 homepage = "https://cornlang.dev/"
 documentation = "https://docs.rs/corn-cli"
@@ -18,8 +18,7 @@ clap = { version = "4.5.31", features = ["derive", "cargo"] }
 colored = "3.0.0"
 
 # (De)serialization
-serde = { version = "1.0.218", features = ["derive"] }
 serde_json = "1.0.140"
 serde_norway = "0.9.42"
 libcorn = { version = "0.10.0", path = ".." }
-toml_edit = { version = "0.22.24", features = ["serde"] }
+toml_edit = { version = "0.24.0", features = ["serde"] }
diff --git a/src/de.rs b/src/de.rs
@@ -370,7 +370,7 @@ impl<'de> Map<'de> {
             Value::Object(values) => Self {
                 values: values
                     .into_iter()
-                    .flat_map(|(key, value)| vec![Value::String(key), value])
+                    .flat_map(|(key, value)| vec![key.into(), value])
                     .collect(),
             },
             _ => unreachable!(),
@@ -474,7 +474,7 @@ impl<'de> EnumAccess<'de> for Enum<'de> {
             Value::Object(obj) => {
                 let first_pair = obj.into_iter().next();
                 if let Some(first_pair) = first_pair {
-                    let value = Value::String(first_pair.0);
+                    let value = first_pair.0.into();
                     let tag = seed.deserialize(&mut Deserializer::from_value(value))?;
                     Ok((tag, Variant::new(Some(first_pair.1))))
                 } else {
diff --git a/src/grammar.pest b/src/grammar.pest
@@ -33,7 +33,7 @@ path = ${
 }
 
 path_seg = _{
-    quoted_path_seg | regular_path_seg
+    integer | quoted_path_seg | regular_path_seg
 }
 
 quoted_path_seg = ${ "'" ~ quoted_path_val ~ "'" }
diff --git a/src/lib.rs b/src/lib.rs
@@ -27,8 +27,37 @@ mod wasm;
 /// The names include their `$` prefix.
 pub type Inputs<'a> = HashMap<&'a str, Value<'a>>;
 
+#[derive(Serialize, Debug, Clone, PartialEq, Eq, Hash)]
+#[serde(untagged)]
+pub enum Key<'a> {
+    String(Cow<'a, str>),
+    Integer(i64),
+}
+
+impl Display for Key<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Key::String(val) => val.to_string(),
+                Key::Integer(val) => val.to_string(),
+            }
+        )
+    }
+}
+
+impl<'a> From<Key<'a>> for Value<'a> {
+    fn from(value: Key<'a>) -> Self {
+        match value {
+            Key::String(val) => Value::String(val),
+            Key::Integer(val) => Value::Integer(val),
+        }
+    }
+}
+
 /// A map of keys to their values.
-pub type Object<'a> = IndexMap<Cow<'a, str>, Value<'a>>;
+pub type Object<'a> = IndexMap<Key<'a>, Value<'a>>;
 
 #[derive(Serialize, Debug, Clone)]
 #[serde(untagged)]
diff --git a/src/parser.rs b/src/parser.rs
@@ -8,7 +8,7 @@ use pest::iterators::Pair;
 use pest::Parser;
 
 use crate::error::{Error, Result};
-use crate::{Inputs, Object, Value};
+use crate::{Inputs, Key, Object, Value};
 
 #[derive(pest_derive::Parser)]
 #[grammar = "grammar.pest"]
@@ -121,7 +121,7 @@ impl<'a> CornParser<'a> {
                     }
                 }
                 _ => unreachable!(),
-            };
+            }
         }
 
         let full_string = if full_string.contains('\n') {
@@ -184,7 +184,7 @@ impl<'a> CornParser<'a> {
                     }
                 }
                 _ => arr.push(self.parse_value(pair)?),
-            };
+            }
         }
 
         Ok(arr)
@@ -240,17 +240,18 @@ impl<'a> CornParser<'a> {
         Ok(obj)
     }
 
-    fn parse_path(path: Pair<Rule>) -> Vec<Cow<str>> {
+    fn parse_path(path: Pair<Rule>) -> Vec<Key> {
         path.into_inner()
             .map(|pair| match pair.as_rule() {
-                Rule::regular_path_seg => Cow::Borrowed(pair.as_str()),
-                Rule::quoted_path_seg => Cow::Owned(
+                Rule::regular_path_seg => Key::String(Cow::Borrowed(pair.as_str())),
+                Rule::quoted_path_seg => Key::String(Cow::Owned(
                     pair.into_inner()
                         .next()
                         .expect("quoted paths should contain an inner value")
                         .as_str()
                         .replace('\\', ""),
-                ),
+                )),
+                Rule::integer => Key::Integer(Self::parse_integer(pair)),
                 _ => unreachable!(),
             })
             .collect::<Vec<_>>()
@@ -262,11 +263,7 @@ impl<'a> CornParser<'a> {
     /// for example `foo.bar` is represented as `["foo", "bar"]`.
     ///
     /// Objects are created up to the required depth recursively.
-    fn add_at_path(
-        mut obj: Object<'a>,
-        path: &[Cow<'a, str>],
-        value: Value<'a>,
-    ) -> Result<Object<'a>> {
+    fn add_at_path(mut obj: Object<'a>, path: &[Key<'a>], value: Value<'a>) -> Result<Object<'a>> {
         let (part, path_rest) = path
             .split_first()
             .expect("paths should contain at least 1 segment");
@@ -289,7 +286,12 @@ impl<'a> CornParser<'a> {
 
                 Ok(obj)
             }
-            _ => Err(Error::InvalidPathError(path.join("."))),
+            _ => Err(Error::InvalidPathError(
+                path.iter()
+                    .map(ToString::to_string)
+                    .collect::<Vec<_>>()
+                    .join("."),
+            )),
         }
     }
 
@@ -400,7 +402,7 @@ fn trim_multiline_string(string: &str) -> String {
 /// If the internal AST parser produces a tree in an invalid structure,
 /// the function will panic.
 /// This indicates a severe error in the library and should never occur.
-pub fn parse(file: &str) -> Result<Value> {
+pub fn parse(file: &str) -> Result<Value<'_>> {
     let rules = AstParser::parse(Rule::config, file);
 
     match rules {
diff --git a/tests/de_tests.rs b/tests/de_tests.rs
@@ -1,6 +1,7 @@
 use corn::from_str;
 use paste::paste;
 use serde::Deserialize;
+use std::collections::HashMap;
 use std::fs;
 
 macro_rules! generate_eq_tests {
@@ -328,6 +329,11 @@ struct NullInArray {
     foo: Vec<Option<u8>>,
 }
 
+#[derive(Deserialize, Debug, PartialEq)]
+struct NumericKeys {
+    foo: HashMap<u32, String>,
+}
+
 #[derive(Deserialize, Debug, PartialEq)]
 struct Object {
     foo: SubObject,
@@ -463,6 +469,7 @@ generate_eq_tests!(
     (mixed_array, MixedArray),
     (null, Null),
     (null_in_array, NullInArray),
+    (numeric_keys, NumericKeys),
     (object, Object),
     (object_in_array, ObjectInArray),
     (readme_example, ReadmeExample),
diff --git a/tests/parser_tests.rs b/tests/parser_tests.rs
@@ -31,6 +31,7 @@ macro_rules! generate_eq_tests {
                     let valid = fs::read_to_string(format!("{root_dir}/assets/outputs/yaml/{test_name}.yml")).unwrap().replace("\r", "");
 
                     let config = parse(input.as_str()).unwrap();
+
                     let serialized = serde_norway::to_string(&config).unwrap().replace("\r", "");
 
                     assert_eq!(serialized.trim(), valid.trim());
@@ -45,6 +46,7 @@ macro_rules! generate_eq_tests {
                     let valid = fs::read_to_string(format!("{root_dir}/assets/outputs/toml/{test_name}.toml")).unwrap().replace("\r", "");
 
                     let config = parse(input.as_str()).unwrap();
+
                     // fall back to default as toml can fail due to no null
                     let serialized = toml_edit::ser::to_string_pretty(&config).unwrap_or_default().replace("\r", "");
 

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+{`
	`2`	`+ foo = { 0 = "low" 33 = "medium" 67 = "high" }`
	`3`	`+}`
-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +foo:
 +  0: low
 +  33: medium
 +  67: high
++
Original file line number	Diff line number	Diff line change
`@@ -33,7 +33,7 @@ path = ${`
`33`	`33`	`}`
`34`	`34`
`35`	`35`	`path_seg = _{`
`36`		`- quoted_path_seg \| regular_path_seg`
	`36`	`+ integer \| quoted_path_seg \| regular_path_seg`
`37`	`37`	`}`
`38`	`38`
`39`	`39`	`quoted_path_seg = ${ "'" ~ quoted_path_val ~ "'" }`