fix untagged enum automatic ordering (#991)

Author: Farossco

typify-impl/src/convert.rs

@@ -7,7 +7,7 @@ use crate::type_entry::{
     EnumTagType, TypeEntry, TypeEntryDetails, TypeEntryEnum, TypeEntryNewtype, TypeEntryStruct,
     Variant, VariantDetails,
 };
-use crate::util::{all_mutually_exclusive, ref_key, StringValidator};
+use crate::util::{all_mutually_exclusive, ref_key, ReorderedInstanceType, StringValidator};
 use log::{debug, info};
 use schemars::schema::{
     ArrayValidation, InstanceType, Metadata, ObjectValidation, Schema, SchemaObject, SingleOrVec,
@@ -672,7 +672,14 @@ impl TypeSpace {
             } => {
                 // Eliminate duplicates (they hold no significance); they
                 // aren't supposed to be there, but we can still handle it.
-                let unique_types = instance_types.iter().collect::<BTreeSet<_>>();
+                // Convert the types into a form that puts integers before
+                // numbers to ensure that integer get matched before numbers in
+                // untagged enum generation.
+                let unique_types = instance_types
+                    .iter()
+                    .copied()
+                    .map(ReorderedInstanceType::from)
+                    .collect::<BTreeSet<_>>();
 
                 // Massage the data into labeled subschemas with the following
                 // format:
@@ -695,8 +702,9 @@ impl TypeSpace {
                 // but why do tomorrow what we could easily to today?
                 let subschemas = unique_types
                     .into_iter()
+                    .map(InstanceType::from)
                     .map(|it| {
-                        let instance_type = Some(SingleOrVec::Single(Box::new(*it)));
+                        let instance_type = Some(SingleOrVec::Single(Box::new(it)));
                         let (label, inner_schema) = match it {
                             InstanceType::Null => (
                                 "null",

typify-impl/src/util.rs

@@ -933,6 +933,63 @@ impl StringValidator {
     }
 }
 
+/// A re-ordering of JSON schema instance types that puts integer values before
+/// number values.
+///
+/// This is used for untagged enum generation to ensure that integer values
+/// are matched before number values.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub(crate) enum ReorderedInstanceType {
+    /// The JSON schema instance type `null`.
+    Null,
+
+    /// The JSON schema instance type `boolean`.
+    Boolean,
+
+    /// The JSON schema instance type `integer`.
+    Integer,
+
+    /// The JSON schema instance type `number`.
+    Number,
+
+    /// The JSON schema instance type `string`.
+    String,
+
+    /// The JSON schema instance type `array`.
+    Array,
+
+    /// The JSON schema instance type `object`.
+    Object,
+}
+
+impl From<InstanceType> for ReorderedInstanceType {
+    fn from(instance_type: InstanceType) -> Self {
+        match instance_type {
+            InstanceType::Null => Self::Null,
+            InstanceType::Boolean => Self::Boolean,
+            InstanceType::Object => Self::Object,
+            InstanceType::Array => Self::Array,
+            InstanceType::Integer => Self::Integer,
+            InstanceType::Number => Self::Number,
+            InstanceType::String => Self::String,
+        }
+    }
+}
+
+impl From<ReorderedInstanceType> for InstanceType {
+    fn from(instance_type: ReorderedInstanceType) -> Self {
+        match instance_type {
+            ReorderedInstanceType::Null => Self::Null,
+            ReorderedInstanceType::Boolean => Self::Boolean,
+            ReorderedInstanceType::Object => Self::Object,
+            ReorderedInstanceType::Array => Self::Array,
+            ReorderedInstanceType::Integer => Self::Integer,
+            ReorderedInstanceType::Number => Self::Number,
+            ReorderedInstanceType::String => Self::String,
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use std::collections::BTreeMap;
@@ -944,7 +1001,7 @@ mod tests {
     };
 
     use crate::{
-        util::{decode_segment, sanitize, schemas_mutually_exclusive, Case},
+        util::{decode_segment, sanitize, schemas_mutually_exclusive, Case, ReorderedInstanceType},
         Name,
     };
 
@@ -1121,4 +1178,22 @@ mod tests {
         assert!(ach.is_valid("Meshach"));
         assert!(!ach.is_valid("Abednego"));
     }
+
+    #[test]
+    fn test_instance_type_ordering() {
+        let null = ReorderedInstanceType::Null;
+        let boolean = ReorderedInstanceType::Boolean;
+        let integer = ReorderedInstanceType::Integer;
+        let number = ReorderedInstanceType::Number;
+        let string = ReorderedInstanceType::String;
+        let array = ReorderedInstanceType::Array;
+        let object = ReorderedInstanceType::Object;
+
+        assert!(null < boolean);
+        assert!(boolean < integer);
+        assert!(integer < number);
+        assert!(number < string);
+        assert!(string < array);
+        assert!(array < object);
+    }
 }

typify/tests/schemas/multiple-instance-types.rs

@@ -41,14 +41,14 @@ pub mod error {
 #[derive(:: serde :: Deserialize, :: serde :: Serialize, Clone, Debug)]
 #[serde(untagged)]
 pub enum IntOrStr {
-    String(::std::string::String),
     Integer(i64),
+    String(::std::string::String),
 }
 impl ::std::fmt::Display for IntOrStr {
     fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
         match self {
-            Self::String(x) => x.fmt(f),
             Self::Integer(x) => x.fmt(f),
+            Self::String(x) => x.fmt(f),
         }
     }
 }
@@ -79,31 +79,31 @@ impl ::std::convert::From<i64> for IntOrStr {
 pub enum OneOfSeveral {
     Null,
     Boolean(bool),
-    Object(::serde_json::Map<::std::string::String, ::serde_json::Value>),
-    Array(::std::vec::Vec<::serde_json::Value>),
-    String(::std::string::String),
     Integer(i64),
+    String(::std::string::String),
+    Array(::std::vec::Vec<::serde_json::Value>),
+    Object(::serde_json::Map<::std::string::String, ::serde_json::Value>),
 }
 impl ::std::convert::From<bool> for OneOfSeveral {
     fn from(value: bool) -> Self {
         Self::Boolean(value)
     }
 }
-impl ::std::convert::From<::serde_json::Map<::std::string::String, ::serde_json::Value>>
-    for OneOfSeveral
-{
-    fn from(value: ::serde_json::Map<::std::string::String, ::serde_json::Value>) -> Self {
-        Self::Object(value)
+impl ::std::convert::From<i64> for OneOfSeveral {
+    fn from(value: i64) -> Self {
+        Self::Integer(value)
     }
 }
 impl ::std::convert::From<::std::vec::Vec<::serde_json::Value>> for OneOfSeveral {
     fn from(value: ::std::vec::Vec<::serde_json::Value>) -> Self {
         Self::Array(value)
     }
 }
-impl ::std::convert::From<i64> for OneOfSeveral {
-    fn from(value: i64) -> Self {
-        Self::Integer(value)
+impl ::std::convert::From<::serde_json::Map<::std::string::String, ::serde_json::Value>>
+    for OneOfSeveral
+{
+    fn from(value: ::serde_json::Map<::std::string::String, ::serde_json::Value>) -> Self {
+        Self::Object(value)
     }
 }
 #[doc = "`ReallyJustNull`"]