From 459263b76320dabcc21cd6b523ea5b2440ba4e0b Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Wed, 14 Dec 2022 12:07:50 -0800
Subject: [PATCH] Refactor reactive scope representation

---
 compiler/forget/src/HIR/BuildReactiveFunction.ts      | 8 +++-----
 compiler/forget/src/HIR/HIR.ts                        | 4 +---
 compiler/forget/src/HIR/PrintReactiveFunction.ts      | 6 +++---
 compiler/forget/src/HIR/PropagateScopeDependencies.ts | 4 ++--
 4 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/compiler/forget/src/HIR/BuildReactiveFunction.ts b/compiler/forget/src/HIR/BuildReactiveFunction.ts
index 2f3af91f55..7d30ba3d98 100644
--- a/compiler/forget/src/HIR/BuildReactiveFunction.ts
+++ b/compiler/forget/src/HIR/BuildReactiveFunction.ts
@@ -68,9 +68,7 @@ class Builder {
   startScope(scope: ReactiveScope): void {
     const block: ReactiveBlock = {
       kind: "block",
-      id: scope.id,
-      range: scope.range,
-      dependencies: scope.dependencies,
+      scope,
       instructions: [],
     };
     this.append(block, undefined);
@@ -80,8 +78,8 @@ class Builder {
 
   visitId(id: InstructionId): void {
     for (let i = 0; i < this.#stack.length; i++) {
-      const scope = this.#stack[i]!;
-      if (scope.kind === "scope" && id >= scope.block.range.end) {
+      const entry = this.#stack[i]!;
+      if (entry.kind === "scope" && id >= entry.block.scope.range.end) {
         this.#stack.length = i;
         break;
       }
diff --git a/compiler/forget/src/HIR/HIR.ts b/compiler/forget/src/HIR/HIR.ts
index a18985a17f..08f769e01f 100644
--- a/compiler/forget/src/HIR/HIR.ts
+++ b/compiler/forget/src/HIR/HIR.ts
@@ -52,9 +52,7 @@ export type ReactiveFunction = {
 
 export type ReactiveBlock = {
   kind: "block";
-  id: ScopeId;
-  range: MutableRange;
-  dependencies: Set<Place>;
+  scope: ReactiveScope;
   instructions: ReactiveBasicBlock;
 };
 
diff --git a/compiler/forget/src/HIR/PrintReactiveFunction.ts b/compiler/forget/src/HIR/PrintReactiveFunction.ts
index 80bfdd1f49..a51e4bbdc1 100644
--- a/compiler/forget/src/HIR/PrintReactiveFunction.ts
+++ b/compiler/forget/src/HIR/PrintReactiveFunction.ts
@@ -36,9 +36,9 @@ export function printReactiveFunction(fn: ReactiveFunction): string {
 
 export function printReactiveBlock(writer: Writer, block: ReactiveBlock): void {
   writer.writeLine(
-    `scope @${block.id} [${block.range.start}:${
-      block.range.end
-    }] deps=[${Array.from(block.dependencies)
+    `scope @${block.scope.id} [${block.scope.range.start}:${
+      block.scope.range.end
+    }] deps=[${Array.from(block.scope.dependencies)
       .map((dep) => printPlace(dep))
       .join(", ")}] {`
   );
diff --git a/compiler/forget/src/HIR/PropagateScopeDependencies.ts b/compiler/forget/src/HIR/PropagateScopeDependencies.ts
index 8f114bec3e..b96c6f38ff 100644
--- a/compiler/forget/src/HIR/PropagateScopeDependencies.ts
+++ b/compiler/forget/src/HIR/PropagateScopeDependencies.ts
@@ -64,9 +64,9 @@ function visit(
           item.instructions,
           scopeDependencies,
           scopeDeclarations,
-          item.range.start
+          item.scope.range.start
         );
-        item.dependencies = scopeDependencies;
+        item.scope.dependencies = scopeDependencies;
         for (const dep of scopeDependencies) {
           // propagate dependencies upward using the same rules as
           // normal dependency collection. child scopes may have dependencies