From ba7e1b0654ece7b698e1ec35c3e98dc84899bce2 Mon Sep 17 00:00:00 2001
From: Michael Sweeney <overthemike@gmail.com>
Date: Sun, 10 May 2026 09:13:22 -0700
Subject: [PATCH 1/3] added initial pass at new methods

---
 src/react/utils/useProxy.ts   |  2 +-
 src/vanilla/utils/proxyMap.ts | 50 ++++++++++++++++++++++++++++-------
 2 files changed, 41 insertions(+), 11 deletions(-)

diff --git a/src/react/utils/useProxy.ts b/src/react/utils/useProxy.ts
index 38bb4322..ad145a00 100644
--- a/src/react/utils/useProxy.ts
+++ b/src/react/utils/useProxy.ts
@@ -33,7 +33,7 @@ export function useProxy<T extends object>(
   ;(snapshot as any)[DUMMY_SYMBOL]
 
   let isRendering = true
-  // eslint-disable-next-line react-hooks/immutability
+
   useLayoutEffect(() => {
     // This is an intentional hack
     // It might not work with React Compiler
diff --git a/src/vanilla/utils/proxyMap.ts b/src/vanilla/utils/proxyMap.ts
index 12219f00..f4a94532 100644
--- a/src/vanilla/utils/proxyMap.ts
+++ b/src/vanilla/utils/proxyMap.ts
@@ -3,13 +3,19 @@ import { proxy, unstable_getInternalStates } from '../../vanilla.ts'
 const { proxyStateMap, snapCache } = unstable_getInternalStates()
 const isProxy = (x: any) => proxyStateMap.has(x)
 
-type InternalProxyObject<K, V> = Map<K, V> & {
-  data: Array<V>
-  index: number
-  epoch: number
-  toJSON: () => Map<K, V>
+type MapGetOrInsert<K, V> = {
+  getOrInsert(key: K, defaultValue: V): V
+  getOrInsertComputed(key: K, callbackFn: (key: K) => V): V
 }
 
+type InternalProxyObject<K, V> = Map<K, V> &
+  Partial<MapGetOrInsert<K, V>> & {
+    data: Array<V>
+    index: number
+    epoch: number
+    toJSON: () => Map<K, V>
+  }
+
 /**
  * Determines if an object is a proxy Map created with proxyMap
  */
@@ -178,12 +184,36 @@ export function proxyMap<K, V>(entries?: Iterable<[K, V]> | undefined | null) {
     toJSON(): Map<K, V> {
       return new Map(this.entries())
     },
-    // [ONLY-TS-5.9.3] [ONLY-TS-5.8.3] [ONLY-TS-5.7.3] [ONLY-TS-5.6.3] @ts-expect-error ignore
-    getOrInsert() {
-      throw new Error('not implemented')
+    // [ONLY-TS-5.9.3] [ONLY-TS-5.8.3] [ONLY-TS-5.7.3] [ONLY-TS-5.6.3] @ts-ignore ignore
+    getOrInsert(key: K, defaultValue: V): V {
+      if (!isProxy(this)) {
+        throw new Error('Cannot perform mutations on a snapshot')
+      }
+      const index = indexMap.get(key)
+      if (index !== undefined) {
+        return this.data[index]!
+      }
+      indexMap.set(key, this.index)
+      this.data[this.index] = defaultValue
+      this.index++
+      this.epoch++
+      return defaultValue
     },
-    getOrInsertComputed() {
-      throw new Error('not implemented')
+    // [ONLY-TS-5.9.3] [ONLY-TS-5.8.3] [ONLY-TS-5.7.3] [ONLY-TS-5.6.3] @ts-ignore ignore
+    getOrInsertComputed(key: K, callbackFn: (key: K) => V): V {
+      if (!isProxy(this)) {
+        throw new Error('Cannot perform mutations on a snapshot')
+      }
+      const index = indexMap.get(key)
+      if (index !== undefined) {
+        return this.data[index]!
+      }
+      const value = callbackFn(key)
+      indexMap.set(key, this.index)
+      this.data[this.index] = value
+      this.index++
+      this.epoch++
+      return value
     },
   }
 

From 4e11f466a595e69c3e49892fdf49365ea0192dfc Mon Sep 17 00:00:00 2001
From: Michael Sweeney <overthemike@gmail.com>
Date: Sun, 10 May 2026 16:05:45 -0700
Subject: [PATCH 2/3] removed unnecessary change

---
 src/react/utils/useProxy.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/react/utils/useProxy.ts b/src/react/utils/useProxy.ts
index ad145a00..38bb4322 100644
--- a/src/react/utils/useProxy.ts
+++ b/src/react/utils/useProxy.ts
@@ -33,7 +33,7 @@ export function useProxy<T extends object>(
   ;(snapshot as any)[DUMMY_SYMBOL]
 
   let isRendering = true
-
+  // eslint-disable-next-line react-hooks/immutability
   useLayoutEffect(() => {
     // This is an intentional hack
     // It might not work with React Compiler

From b0b71b786eb26cb06a3764db1cf6636be2657c22 Mon Sep 17 00:00:00 2001
From: daishi <daishi@axlight.com>
Date: Mon, 11 May 2026 10:15:29 +0900
Subject: [PATCH 3/3] eliminate type hack

---
 src/vanilla/utils/proxyMap.ts | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/src/vanilla/utils/proxyMap.ts b/src/vanilla/utils/proxyMap.ts
index f4a94532..6bcc24e3 100644
--- a/src/vanilla/utils/proxyMap.ts
+++ b/src/vanilla/utils/proxyMap.ts
@@ -3,19 +3,13 @@ import { proxy, unstable_getInternalStates } from '../../vanilla.ts'
 const { proxyStateMap, snapCache } = unstable_getInternalStates()
 const isProxy = (x: any) => proxyStateMap.has(x)
 
-type MapGetOrInsert<K, V> = {
-  getOrInsert(key: K, defaultValue: V): V
-  getOrInsertComputed(key: K, callbackFn: (key: K) => V): V
+type InternalProxyObject<K, V> = Map<K, V> & {
+  data: Array<V>
+  index: number
+  epoch: number
+  toJSON: () => Map<K, V>
 }
 
-type InternalProxyObject<K, V> = Map<K, V> &
-  Partial<MapGetOrInsert<K, V>> & {
-    data: Array<V>
-    index: number
-    epoch: number
-    toJSON: () => Map<K, V>
-  }
-
 /**
  * Determines if an object is a proxy Map created with proxyMap
  */