refactor(value): migrate Value::Set to Set storage abstraction (#778)

Switch Value::Set from Rc<BTreeSet<Value>> to Rc<Set>, wiring the
previously-merged Set wrapper struct (#740) into the enum and updating
all call sites across interpreter, RVM, builtins, serialization, and
languages. Mirrors the merged Object migration (#736).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Copilot-Session: fc92437e-8820-49a4-ba5f-ec82a79f1221

Author: anakrish

src/builtins/json_patch.rs

@@ -87,7 +87,7 @@ impl EditNode {
                     set.insert(value.render()?);
                     enforce_limit()?;
                 }
-                Value::Set(crate::Rc::new(set))
+                Value::from_set(set)
             }
         })
     }

src/builtins/sets.rs

@@ -10,8 +10,6 @@ use crate::lexer::Span;
 use crate::value::Value;
 use crate::*;
 
-use alloc::collections::BTreeSet;
-
 use anyhow::{bail, Result};
 
 pub fn register(m: &mut builtins::BuiltinsMap<&'static str, builtins::BuiltinFcn>) {
@@ -24,19 +22,19 @@ pub fn register(m: &mut builtins::BuiltinsMap<&'static str, builtins::BuiltinFcn
 pub fn intersection(expr1: &Expr, expr2: &Expr, v1: Value, v2: Value) -> Result<Value> {
     let s1 = ensure_set("intersection", expr1, v1)?;
     let s2 = ensure_set("intersection", expr2, v2)?;
-    Ok(Value::from_set(s1.intersection(&s2).cloned().collect()))
+    Ok(Value::from(s1.intersection(&s2)))
 }
 
 pub fn union(expr1: &Expr, expr2: &Expr, v1: Value, v2: Value) -> Result<Value> {
     let s1 = ensure_set("union", expr1, v1)?;
     let s2 = ensure_set("union", expr2, v2)?;
-    Ok(Value::from_set(s1.union(&s2).cloned().collect()))
+    Ok(Value::from(s1.union(&s2)))
 }
 
 pub fn difference(expr1: &Expr, expr2: &Expr, v1: Value, v2: Value) -> Result<Value> {
     let s1 = ensure_set("difference", expr1, v1)?;
     let s2 = ensure_set("difference", expr2, v2)?;
-    Ok(Value::from_set(s1.difference(&s2).cloned().collect()))
+    Ok(Value::from(s1.difference(&s2)))
 }
 
 fn binary_set_union(
@@ -49,7 +47,7 @@ fn binary_set_union(
     ensure_args_count(span, name, params, args, 2)?;
     let left = ensure_set(name, &params[0], args[0].clone())?;
     let right = ensure_set(name, &params[1], args[1].clone())?;
-    Ok(Value::from_set(left.union(&right).cloned().collect()))
+    Ok(Value::from(left.union(&right)))
 }
 
 fn binary_set_intersection(
@@ -62,9 +60,7 @@ fn binary_set_intersection(
     ensure_args_count(span, name, params, args, 2)?;
     let left = ensure_set(name, &params[0], args[0].clone())?;
     let right = ensure_set(name, &params[1], args[1].clone())?;
-    Ok(Value::from_set(
-        left.intersection(&right).cloned().collect(),
-    ))
+    Ok(Value::from(left.intersection(&right)))
 }
 
 fn intersection_of_set_of_sets(
@@ -77,7 +73,7 @@ fn intersection_of_set_of_sets(
     ensure_args_count(span, name, params, args, 1)?;
     let set = ensure_set(name, &params[0], args[0].clone())?;
 
-    let mut res = BTreeSet::new();
+    let mut res = crate::value::Set::new();
     let mut first = true;
 
     for s in set.iter() {
@@ -92,11 +88,11 @@ fn intersection_of_set_of_sets(
             res.clone_from(s);
             first = false;
         } else {
-            res = res.intersection(s).cloned().collect();
+            res = res.intersection(s);
         }
     }
 
-    Ok(Value::from_set(res))
+    Ok(Value::from(res))
 }
 
 fn union_of_set_of_sets(
@@ -109,7 +105,7 @@ fn union_of_set_of_sets(
     ensure_args_count(span, name, params, args, 1)?;
     let set = ensure_set(name, &params[0], args[0].clone())?;
 
-    let mut res = BTreeSet::new();
+    let mut res = crate::value::Set::new();
 
     for s in set.iter() {
         let s = match s {
@@ -119,8 +115,8 @@ fn union_of_set_of_sets(
             ),
         };
 
-        res = res.union(s).cloned().collect();
+        res = res.union(s);
     }
 
-    Ok(Value::from_set(res))
+    Ok(Value::from(res))
 }

src/builtins/utils.rs

@@ -5,13 +5,11 @@
 use crate::ast::{Expr, Ref};
 use crate::lexer::Span;
 use crate::number::Number;
-use crate::value::Object;
+use crate::value::{Object, Set};
 use crate::Rc;
 use crate::Value;
 use crate::*;
 
-use alloc::collections::BTreeSet;
-
 use anyhow::{bail, Result};
 
 #[inline]
@@ -159,7 +157,7 @@ pub fn ensure_array(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<Vec<Value>>> {
     })
 }
 
-pub fn ensure_set(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<BTreeSet<Value>>> {
+pub fn ensure_set(fcn: &str, arg: &Expr, v: Value) -> Result<Rc<Set>> {
     Ok(match v {
         Value::Set(s) => s,
         _ => {

src/languages/azure_policy/compiler/metadata.rs

@@ -17,7 +17,7 @@ use crate::languages::azure_policy::ast::{
     Condition, EffectKind, FieldKind, JsonValue, Lhs, OperatorKind, PolicyDefinition, PolicyRule,
     ValueOrExpr,
 };
-use crate::{Rc, Value};
+use crate::Value;
 
 use super::core::Compiler;
 
@@ -237,7 +237,7 @@ impl Compiler {
                 .iter()
                 .map(|p| Value::String(p.name.as_str().into()))
                 .collect();
-            annot.insert("parameter_names".to_string(), Value::Set(Rc::new(set)));
+            annot.insert("parameter_names".to_string(), Value::from_set(set));
         }
 
         // Extra fields: policyType → policy_type, id → policy_id, name → policy_name.
@@ -279,6 +279,6 @@ fn insert_string_set_annotation(
             .iter()
             .map(|s| Value::String(s.as_str().into()))
             .collect();
-        annot.insert(key.to_string(), Value::Set(Rc::new(set)));
+        annot.insert(key.to_string(), Value::from_set(set));
     }
 }

src/languages/azure_rbac/builtins/lists.rs

@@ -1,9 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT License.
 
-use alloc::collections::BTreeSet;
-
-use crate::value::Value;
+use crate::value::{Set, Value};
 
 use super::evaluator::RbacBuiltinError;
 
@@ -28,7 +26,7 @@ fn list_contains_values(list: &[Value], needle: &Value) -> bool {
 }
 
 // For sets, treat a list/set needle as "all elements are contained".
-fn set_contains_values(set: &BTreeSet<Value>, needle: &Value) -> bool {
+fn set_contains_values(set: &Set, needle: &Value) -> bool {
     match *needle {
         // For collection needles, require all elements to be present.
         Value::Array(ref right_list) => right_list.iter().all(|item| set.contains(item)),

src/languages/rego/compiler/expressions/collection_literals.rs

@@ -40,7 +40,7 @@ pub(in crate::languages::rego::compiler) fn try_eval_const(expr: &Expr) -> Optio
             .iter()
             .map(|i| try_eval_const(i.as_ref()))
             .collect::<Option<BTreeSet<_>>>()
-            .map(|s| Value::Set(Rc::new(s))),
+            .map(Value::from_set),
         Expr::Object { fields, .. } => fields
             .iter()
             .map(|(_, k, v)| Some((try_eval_const(k.as_ref())?, try_eval_const(v.as_ref())?)))
@@ -92,7 +92,7 @@ impl<'a> Compiler<'a> {
             items.iter().map(|i| try_eval_const(i.as_ref())).collect();
         if let Some(values) = all_const {
             let dest = self.alloc_register();
-            let literal_idx = self.add_literal(Value::Set(Rc::new(values)));
+            let literal_idx = self.add_literal(Value::from_set(values));
             self.emit_instruction(Instruction::Load { dest, literal_idx }, span);
             return Ok(dest);
         }

src/rvm/program/metadata.rs

@@ -173,7 +173,7 @@ impl MetadataValue {
                             .collect(),
                     )
                 } else {
-                    MetadataValue::List(set.iter().map(MetadataValue::from_value).collect())
+                    MetadataValue::List(set.iter_sorted().map(MetadataValue::from_value).collect())
                 }
             }
             Value::Object(ref obj) => {
@@ -202,7 +202,7 @@ impl MetadataValue {
                 for s in set {
                     bset.insert(Value::String(s.as_str().into()));
                 }
-                Value::Set(Rc::new(bset))
+                Value::from_set(bset)
             }
             MetadataValue::Bool(b) => Value::Bool(b),
             MetadataValue::Integer(n) => Value::from(n),
@@ -301,7 +301,7 @@ mod tests {
         let mut set = BTreeSet::new();
         set.insert(Value::String("a".into()));
         set.insert(Value::String("b".into()));
-        let v = Value::Set(Rc::new(set));
+        let v = Value::from_set(set);
         assert_round_trip(&v, &v);
     }
 
@@ -328,11 +328,14 @@ mod tests {
         let mut set = BTreeSet::new();
         set.insert(Value::String("a".into()));
         set.insert(Value::from(1_i64));
-        let v = Value::Set(Rc::new(set));
+        let v = Value::from_set(set);
         let mv = MetadataValue::from_value(&v);
-        assert!(
-            matches!(mv, MetadataValue::List(_)),
-            "mixed-type set should produce List, got {mv:?}"
+        assert_eq!(
+            mv,
+            MetadataValue::List(alloc::vec![
+                MetadataValue::Integer(1),
+                MetadataValue::String("a".into()),
+            ])
         );
     }
 

src/rvm/program/serialization/value.rs

@@ -11,8 +11,8 @@ use serde::ser::{SerializeSeq as _, SerializeTuple as _};
 use serde::{Deserialize, Serialize};
 
 use crate::number::Number;
-use crate::value::Object;
 use crate::value::Value;
+use crate::value::{Object, Set};
 
 const VARIANT_NULL: u32 = 0;
 const VARIANT_BOOL: u32 = 1;
@@ -118,15 +118,15 @@ impl<'a> Serialize for BinaryValueSlice<'a> {
     }
 }
 
-struct BinarySetRef<'a>(&'a BTreeSet<Value>);
+struct BinarySetRef<'a>(&'a Set);
 
 impl<'a> Serialize for BinarySetRef<'a> {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
     where
         S: serde::Serializer,
     {
         let mut seq = serializer.serialize_seq(Some(self.0.len()))?;
-        for value in self.0.iter() {
+        for value in self.0.iter_sorted() {
             seq.serialize_element(&BinaryValueRef(value))?;
         }
         seq.end()

src/rvm/vm/arithmetic.rs

@@ -30,9 +30,7 @@ impl RegoVM {
         match (a, b) {
             (&Value::Number(ref x), &Value::Number(ref y)) => Ok(Value::from(x.sub(y)?)),
             (&Value::Set(ref left), &Value::Set(ref right)) => {
-                let diff: alloc::collections::BTreeSet<Value> =
-                    left.difference(right).cloned().collect();
-                Ok(Value::from(diff))
+                Ok(Value::from(left.difference(right)))
             }
             _ => Err(VmError::InvalidSubtraction {
                 left: a.clone(),