From 45216dc3d9112251feeaa1e981fe887156d5f83d Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Tue, 27 Feb 2024 11:39:22 -0800
Subject: [PATCH] Track next scope id on Environment

Currently we allocate all reactive scopes during a single pass,
InferReactiveScopeVariables, using a local incrementing number to assign
ScopeIds. This means we can't easily create additional scopes later since we
don't know the next available scope id.

Here we add `Environment.nextScopeId` and use that to synthesize scope ids.
---
 .../babel-plugin-react-forget/src/HIR/Environment.ts       | 7 +++++++
 .../src/ReactiveScopes/InferReactiveScopeVariables.ts      | 3 +--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/compiler/packages/babel-plugin-react-forget/src/HIR/Environment.ts b/compiler/packages/babel-plugin-react-forget/src/HIR/Environment.ts
index bed0c5be76..e50486d2f4 100644
--- a/compiler/packages/babel-plugin-react-forget/src/HIR/Environment.ts
+++ b/compiler/packages/babel-plugin-react-forget/src/HIR/Environment.ts
@@ -24,10 +24,12 @@ import {
   FunctionType,
   IdentifierId,
   PolyType,
+  ScopeId,
   Type,
   ValueKind,
   makeBlockId,
   makeIdentifierId,
+  makeScopeId,
 } from "./HIR";
 import {
   BuiltInMixedReadonlyId,
@@ -412,6 +414,7 @@ export class Environment {
   #shapes: ShapeRegistry;
   #nextIdentifer: number = 0;
   #nextBlock: number = 0;
+  #nextScope: number = 0;
   config: EnvironmentConfig;
 
   #contextIdentifiers: Set<t.Identifier>;
@@ -460,6 +463,10 @@ export class Environment {
     return makeBlockId(this.#nextBlock++);
   }
 
+  get nextScopeId(): ScopeId {
+    return makeScopeId(this.#nextScope++);
+  }
+
   isContextIdentifier(node: t.Identifier): boolean {
     return this.#contextIdentifiers.has(node);
   }
diff --git a/compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/InferReactiveScopeVariables.ts b/compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/InferReactiveScopeVariables.ts
index c03dd726ae..436d3b48bf 100644
--- a/compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/InferReactiveScopeVariables.ts
+++ b/compiler/packages/babel-plugin-react-forget/src/ReactiveScopes/InferReactiveScopeVariables.ts
@@ -12,7 +12,6 @@ import {
   IdentifierId,
   Instruction,
   makeInstructionId,
-  makeScopeId,
   Place,
   ReactiveScope,
 } from "../HIR/HIR";
@@ -102,7 +101,7 @@ export function inferReactiveScopeVariables(fn: HIRFunction): void {
     let scope = scopes.get(groupIdentifier);
     if (scope === undefined) {
       scope = {
-        id: makeScopeId(scopes.size),
+        id: fn.env.nextScopeId,
         range: identifier.mutableRange,
         dependencies: new Set(),
         declarations: new Map(),