From 9fbec983d8769a646429cdcd19722d949d036a99 Mon Sep 17 00:00:00 2001
From: Justin Ridgewell <justin@ridgewell.name>
Date: Fri, 26 Jan 2024 21:44:38 -0500
Subject: [PATCH 1/4] Update the polyfill to the lastest API

---
 package-lock.json           |  8 ++---
 src/fork.ts                 |  6 ++--
 src/index.ts                | 47 ++++++-------------------
 src/mapping.ts              | 27 +++++++--------
 src/promise-polyfill.ts     |  4 +--
 src/snapshot.ts             | 16 +++++++++
 src/storage.ts              | 30 ++++++++++------
 src/types.ts                |  1 +
 src/variable.ts             | 43 +++++++++++++++++++++++
 src/wrap.ts                 | 18 ++++++++++
 tests/async-context.test.ts | 68 ++++++++++++++++++-------------------
 11 files changed, 163 insertions(+), 105 deletions(-)
 create mode 100644 src/snapshot.ts
 create mode 100644 src/types.ts
 create mode 100644 src/variable.ts
 create mode 100644 src/wrap.ts

diff --git a/package-lock.json b/package-lock.json
index c5c964b..cb18809 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8,9 +8,6 @@
       "name": "proposal-async-context",
       "version": "1.0.0",
       "license": "CC0-1.0",
-      "dependencies": {
-        "prettier": "2.8.7"
-      },
       "devDependencies": {
         "@esbuild-kit/cjs-loader": "2.4.1",
         "@esbuild-kit/esm-loader": "2.5.4",
@@ -19,6 +16,7 @@
         "@types/node": "18.11.18",
         "ecmarkup": "^16.1.1",
         "mocha": "10.2.0",
+        "prettier": "2.8.7",
         "typescript": "4.9.4"
       }
     },
@@ -2093,6 +2091,7 @@
       "version": "2.8.7",
       "resolved": "https://registry.npmjs.org/prettier/-/prettier-2.8.7.tgz",
       "integrity": "sha512-yPngTo3aXUUmyuTjeTUT75txrf+aMh9FiD7q9ZE/i6r0bPb22g4FsE6Y338PQX1bmfy08i9QQCB7/rcUAVntfw==",
+      "dev": true,
       "bin": {
         "prettier": "bin-prettier.js"
       },
@@ -4229,7 +4228,8 @@
     "prettier": {
       "version": "2.8.7",
       "resolved": "https://registry.npmjs.org/prettier/-/prettier-2.8.7.tgz",
-      "integrity": "sha512-yPngTo3aXUUmyuTjeTUT75txrf+aMh9FiD7q9ZE/i6r0bPb22g4FsE6Y338PQX1bmfy08i9QQCB7/rcUAVntfw=="
+      "integrity": "sha512-yPngTo3aXUUmyuTjeTUT75txrf+aMh9FiD7q9ZE/i6r0bPb22g4FsE6Y338PQX1bmfy08i9QQCB7/rcUAVntfw==",
+      "dev": true
     },
     "prex": {
       "version": "0.4.9",
diff --git a/src/fork.ts b/src/fork.ts
index 0b30195..8d36dd7 100644
--- a/src/fork.ts
+++ b/src/fork.ts
@@ -1,5 +1,5 @@
 import type { Mapping } from "./mapping";
-import type { AsyncContext } from "./index";
+import type { Variable } from "./Variable";
 
 /**
  * FrozenRevert holds a frozen Mapping that will be simply restored when the
@@ -40,11 +40,11 @@ export class FrozenRevert {
  * clone to the prior state.
  */
 export class Revert<T> {
-  #key: AsyncContext<T>;
+  #key: Variable<T>;
   #has: boolean;
   #prev: T | undefined;
 
-  constructor(mapping: Mapping, key: AsyncContext<T>) {
+  constructor(mapping: Mapping, key: Variable<T>) {
     this.#key = key;
     this.#has = mapping.has(key);
     this.#prev = mapping.get(key);
diff --git a/src/index.ts b/src/index.ts
index ec5977b..0105c4c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,37 +1,10 @@
-import { Storage } from "./storage";
-
-type AnyFunc<T> = (this: T, ...args: any) => any;
-
-export class AsyncContext<T> {
-  static wrap<F extends AnyFunc<any>>(fn: F): F {
-    const snapshot = Storage.snapshot();
-
-    function wrap(this: ThisType<F>, ...args: Parameters<F>): ReturnType<F> {
-      const head = Storage.switch(snapshot);
-      try {
-        return fn.apply(this, args);
-      } finally {
-        Storage.restore(head);
-      }
-    }
-
-    return wrap as unknown as F;
-  }
-
-  run<F extends AnyFunc<null>>(
-    value: T,
-    fn: F,
-    ...args: Parameters<F>
-  ): ReturnType<F> {
-    const revert = Storage.set(this, value);
-    try {
-      return fn.apply(null, args);
-    } finally {
-      Storage.restore(revert);
-    }
-  }
-
-  get(): T | undefined {
-    return Storage.get(this);
-  }
-}
+import { Snapshot } from "./snapshot";
+import { Variable } from "./variable";
+import { wrap } from "./wrap";
+
+export const AsyncContext = {
+  Snapshot,
+  Variable,
+  wrap,
+};
+export { Snapshot, Variable, wrap };
diff --git a/src/mapping.ts b/src/mapping.ts
index bcd2dcf..f6a8417 100644
--- a/src/mapping.ts
+++ b/src/mapping.ts
@@ -1,39 +1,38 @@
-import type { AsyncContext } from "./index";
+import type { Variable } from "./variable";
 
 /**
- * Stores all AsyncContext data, and tracks whether any snapshots have been
+ * Stores all Variable data, and tracks whether any snapshots have been
  * taken of the current data.
  */
 export class Mapping {
-  #data: Map<AsyncContext<unknown>, unknown> | null;
+  #data: Map<Variable<unknown>, unknown>;
 
   /**
    * If a snapshot of this data is taken, then further modifications cannot be
    * made directly. Instead, set/delete will clone this Mapping and modify
    * _that_ instance.
    */
-  #frozen: boolean;
+  #frozen = false;
 
-  constructor(data: Map<AsyncContext<unknown>, unknown> | null) {
+  constructor(data: Map<Variable<unknown>, unknown>) {
     this.#data = data;
-    this.#frozen = data === null;
   }
 
-  has<T>(key: AsyncContext<T>): boolean {
-    return this.#data?.has(key) || false;
+  has<T>(key: Variable<T>): boolean {
+    return this.#data.has(key) || false;
   }
 
-  get<T>(key: AsyncContext<T>): T | undefined {
-    return this.#data?.get(key) as T | undefined;
+  get<T>(key: Variable<T>): T | undefined {
+    return this.#data.get(key) as T | undefined;
   }
 
   /**
    * Like the standard Map.p.set, except that we will allocate a new Mapping
    * instance if this instance is frozen.
    */
-  set<T>(key: AsyncContext<T>, value: T): Mapping {
+  set<T>(key: Variable<T>, value: T): Mapping {
     const mapping = this.#fork();
-    mapping.#data!.set(key, value);
+    mapping.#data.set(key, value);
     return mapping;
   }
 
@@ -41,9 +40,9 @@ export class Mapping {
    * Like the standard Map.p.delete, except that we will allocate a new Mapping
    * instance if this instance is frozen.
    */
-  delete<T>(key: AsyncContext<T>): Mapping {
+  delete<T>(key: Variable<T>): Mapping {
     const mapping = this.#fork();
-    mapping.#data!.delete(key);
+    mapping.#data.delete(key);
     return mapping;
   }
 
diff --git a/src/promise-polyfill.ts b/src/promise-polyfill.ts
index 282109b..4746336 100644
--- a/src/promise-polyfill.ts
+++ b/src/promise-polyfill.ts
@@ -1,10 +1,10 @@
 import { AsyncContext } from "./index";
 
-type AnyFunc = (...args: any) => any;
+import type { AnyFunc } from "./types";
 
 export const nativeThen = Promise.prototype.then;
 
-function wrapFn<F extends AnyFunc>(fn: F | null | undefined) {
+function wrapFn<F extends AnyFunc<any>>(fn: F | null | undefined) {
   if (typeof fn !== "function") return undefined;
   return AsyncContext.wrap(fn);
 }
diff --git a/src/snapshot.ts b/src/snapshot.ts
new file mode 100644
index 0000000..5840b92
--- /dev/null
+++ b/src/snapshot.ts
@@ -0,0 +1,16 @@
+import { Storage } from "./storage";
+
+import type { AnyFunc } from "./types";
+
+export class Snapshot {
+  #snapshot = Storage.snapshot();
+
+  run<F extends AnyFunc<any>>(fn: F, ...args: Parameters<F>) {
+    const revert = Storage.switch(this.#snapshot);
+    try {
+      return fn.apply(this, args);
+    } finally {
+      Storage.restore(revert);
+    }
+  }
+}
diff --git a/src/storage.ts b/src/storage.ts
index d67fcb1..e415455 100644
--- a/src/storage.ts
+++ b/src/storage.ts
@@ -1,36 +1,44 @@
 import { Mapping } from "./mapping";
 import { FrozenRevert, Revert } from "./fork";
-import type { AsyncContext } from "./index";
+
+import type { Variable } from "./variable";
 
 /**
  * Storage is the (internal to the language) storage container of all
- * AsyncContext data.
+ * Variable data.
  *
- * None of the methods here are exposed to users, they're only exposed to the AsyncContext class.
+ * None of the methods here are exposed to users, they're only exposed internally.
  */
 export class Storage {
-  static #current: Mapping = new Mapping(null);
+  static #current: Mapping = new Mapping(new Map());
+
+  /**
+   * Has checks if the Variable has a value.
+   */
+  static has<T>(key: Variable<T>): boolean {
+    return this.#current.has(key);
+  }
 
   /**
-   * Get retrieves the current value assigned to the AsyncContext.
+   * Get retrieves the current value assigned to the Variable.
    */
-  static get<T>(key: AsyncContext<T>): T | undefined {
+  static get<T>(key: Variable<T>): T | undefined {
     return this.#current.get(key);
   }
 
   /**
-   * Set assigns a new value to the AsyncContext, returning a revert that can
+   * Set assigns a new value to the Variable, returning a revert that can
    * undo the modification at a later time.
    */
-  static set<T>(key: AsyncContext<T>, value: T): FrozenRevert | Revert<T> {
+  static set<T>(key: Variable<T>, value: T): FrozenRevert | Revert<T> {
     // If the Mappings are frozen (someone has snapshot it), then modifying the
     // mappings will return a clone containing the modification.
     const current = this.#current;
-    const undo = current.isFrozen()
+    const revert = current.isFrozen()
       ? new FrozenRevert(current)
-      : new Revert(current, key);
+      : new Revert<T>(current, key);
     this.#current = this.#current.set(key, value);
-    return undo;
+    return revert;
   }
 
   /**
diff --git a/src/types.ts b/src/types.ts
new file mode 100644
index 0000000..bb97783
--- /dev/null
+++ b/src/types.ts
@@ -0,0 +1 @@
+export type AnyFunc<T> = (this: T, ...args: any) => any;
diff --git a/src/variable.ts b/src/variable.ts
new file mode 100644
index 0000000..bb45b6c
--- /dev/null
+++ b/src/variable.ts
@@ -0,0 +1,43 @@
+import { Storage } from "./storage";
+
+import type { AnyFunc } from "./types";
+
+export interface VariableOptions<T> {
+  name?: string;
+  defaultValue?: T;
+}
+
+export class Variable<T> {
+  #name = "";
+  #defaultValue: T | undefined;
+
+  constructor(options?: VariableOptions<T>) {
+    if (options) {
+      if ("name" in options) {
+        this.#name = String(options.name);
+      }
+      this.#defaultValue = options.defaultValue;
+    }
+  }
+
+  get name() {
+    return this.#name;
+  }
+
+  run<F extends AnyFunc<null>>(
+    value: T,
+    fn: F,
+    ...args: Parameters<F>
+  ): ReturnType<F> {
+    const revert = Storage.set(this, value);
+    try {
+      return fn.apply(null, args);
+    } finally {
+      Storage.restore(revert);
+    }
+  }
+
+  get(): T | undefined {
+    return Storage.has(this) ? Storage.get(this) : this.#defaultValue;
+  }
+}
diff --git a/src/wrap.ts b/src/wrap.ts
new file mode 100644
index 0000000..b96c4e7
--- /dev/null
+++ b/src/wrap.ts
@@ -0,0 +1,18 @@
+import { Storage } from "./storage";
+
+import type { AnyFunc } from "./types";
+
+export function wrap<F extends AnyFunc<any>>(fn: F): F {
+  const snapshot = Storage.snapshot();
+
+  function wrap(this: ThisType<F>, ...args: Parameters<F>): ReturnType<F> {
+    const revert = Storage.switch(snapshot);
+    try {
+      return fn.apply(this, args);
+    } finally {
+      Storage.restore(revert);
+    }
+  }
+
+  return wrap as unknown as F;
+}
diff --git a/tests/async-context.test.ts b/tests/async-context.test.ts
index f4b5376..f13f5ab 100644
--- a/tests/async-context.test.ts
+++ b/tests/async-context.test.ts
@@ -16,7 +16,7 @@ function test(name: string, fn: () => void) {
     fn();
 
     // Ensure we're running from a new state, which won't be frozen.
-    const throwaway = new AsyncContext<null>();
+    const throwaway = new AsyncContext.Variable<null>();
     throwaway.run(null, fn);
 
     throwaway.run(null, () => {
@@ -31,7 +31,7 @@ function test(name: string, fn: () => void) {
 describe("sync", () => {
   describe("run and get", () => {
     test("has initial undefined state", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
 
       const actual = ctx.get();
 
@@ -39,7 +39,7 @@ describe("sync", () => {
     });
 
     test("return value", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const expected = { id: 1 };
 
       const actual = ctx.run({ id: 2 }, () => expected);
@@ -48,7 +48,7 @@ describe("sync", () => {
     });
 
     test("get returns current context value", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const expected = { id: 1 };
 
       ctx.run(expected, () => {
@@ -57,7 +57,7 @@ describe("sync", () => {
     });
 
     test("get within nesting contexts", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -72,8 +72,8 @@ describe("sync", () => {
     });
 
     test("get within nesting different contexts", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -94,7 +94,7 @@ describe("sync", () => {
 
   describe("wrap", () => {
     test("stores initial undefined state", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const wrapped = AsyncContext.wrap(() => ctx.get());
 
       ctx.run({ id: 1 }, () => {
@@ -103,7 +103,7 @@ describe("sync", () => {
     });
 
     test("stores current state", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const expected = { id: 1 };
 
       const wrap = ctx.run(expected, () => {
@@ -118,7 +118,7 @@ describe("sync", () => {
     });
 
     test("runs within wrap", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -157,7 +157,7 @@ describe("sync", () => {
     });
 
     test("runs within wrap", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -196,8 +196,8 @@ describe("sync", () => {
     });
 
     test("runs different context within wrap", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -242,8 +242,8 @@ describe("sync", () => {
     });
 
     test("runs different context within wrap, 2", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -288,7 +288,7 @@ describe("sync", () => {
     });
 
     test("wrap within nesting contexts", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -323,8 +323,8 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 
@@ -365,9 +365,9 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts, 2", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
-      const c = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
+      const c = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
       const third = { id: 3 };
@@ -403,9 +403,9 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts, 3", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
-      const c = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
+      const c = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
       const third = { id: 3 };
@@ -443,9 +443,9 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts, 4", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
-      const c = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
+      const c = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
       const third = { id: 3 };
@@ -483,9 +483,9 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts, 5", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
-      const c = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
+      const c = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
       const third = { id: 3 };
@@ -524,9 +524,9 @@ describe("sync", () => {
     });
 
     test("wrap within nesting different contexts, 6", () => {
-      const a = new AsyncContext<Value>();
-      const b = new AsyncContext<Value>();
-      const c = new AsyncContext<Value>();
+      const a = new AsyncContext.Variable<Value>();
+      const b = new AsyncContext.Variable<Value>();
+      const c = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
       const third = { id: 3 };
@@ -565,7 +565,7 @@ describe("sync", () => {
     });
 
     test("wrap out of order", () => {
-      const ctx = new AsyncContext<Value>();
+      const ctx = new AsyncContext.Variable<Value>();
       const first = { id: 1 };
       const second = { id: 2 };
 

From e46d24ebad7436a4af9d5333c27dc49e022afc59 Mon Sep 17 00:00:00 2001
From: Justin Ridgewell <justin@ridgewell.name>
Date: Fri, 26 Jan 2024 23:31:35 -0500
Subject: [PATCH 2/4] Fix filename case

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

diff --git a/src/fork.ts b/src/fork.ts
index 8d36dd7..9a3ef1a 100644
--- a/src/fork.ts
+++ b/src/fork.ts
@@ -1,5 +1,5 @@
 import type { Mapping } from "./mapping";
-import type { Variable } from "./Variable";
+import type { Variable } from "./variable";
 
 /**
  * FrozenRevert holds a frozen Mapping that will be simply restored when the

From 18f043e84b0d7d1a7a492c21ba6e536ddbb8e3a2 Mon Sep 17 00:00:00 2001
From: Justin Ridgewell <justin@ridgewell.name>
Date: Sat, 10 Feb 2024 00:03:14 -0500
Subject: [PATCH 3/4] Move wrap onto Snapshot

---
 src/index.ts                |  4 +--
 src/snapshot.ts             | 32 ++++++++++++++++++-----
 src/wrap.ts                 | 18 -------------
 tests/async-context.test.ts | 52 ++++++++++++++++++-------------------
 4 files changed, 53 insertions(+), 53 deletions(-)
 delete mode 100644 src/wrap.ts

diff --git a/src/index.ts b/src/index.ts
index 0105c4c..2279b32 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,10 +1,8 @@
 import { Snapshot } from "./snapshot";
 import { Variable } from "./variable";
-import { wrap } from "./wrap";
 
 export const AsyncContext = {
   Snapshot,
   Variable,
-  wrap,
 };
-export { Snapshot, Variable, wrap };
+export { Snapshot, Variable };
diff --git a/src/snapshot.ts b/src/snapshot.ts
index 5840b92..3edb175 100644
--- a/src/snapshot.ts
+++ b/src/snapshot.ts
@@ -1,16 +1,36 @@
 import { Storage } from "./storage";
 
+import type { FrozenRevert } from "./fork";
 import type { AnyFunc } from "./types";
 
 export class Snapshot {
   #snapshot = Storage.snapshot();
 
-  run<F extends AnyFunc<any>>(fn: F, ...args: Parameters<F>) {
-    const revert = Storage.switch(this.#snapshot);
-    try {
-      return fn.apply(this, args);
-    } finally {
-      Storage.restore(revert);
+  static wrap<F extends AnyFunc<any>>(fn: F): F {
+    const snapshot = Storage.snapshot();
+
+    function wrap(this: ThisType<F>, ...args: Parameters<F>): ReturnType<F> {
+      return run(fn, this, args, snapshot);
     }
+
+    return wrap as unknown as F;
+  }
+
+  run<F extends AnyFunc<null>>(fn: F, ...args: Parameters<F>) {
+    return run(fn, null as any, args, this.#snapshot);
+  }
+}
+
+function run<F extends AnyFunc<any>>(
+  fn: F,
+  context: ThisType<F>,
+  args: any[],
+  snapshot: FrozenRevert
+): ReturnType<F> {
+  const revert = Storage.switch(snapshot);
+  try {
+    return fn.apply(context, args);
+  } finally {
+    Storage.restore(revert);
   }
 }
diff --git a/src/wrap.ts b/src/wrap.ts
deleted file mode 100644
index b96c4e7..0000000
--- a/src/wrap.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import { Storage } from "./storage";
-
-import type { AnyFunc } from "./types";
-
-export function wrap<F extends AnyFunc<any>>(fn: F): F {
-  const snapshot = Storage.snapshot();
-
-  function wrap(this: ThisType<F>, ...args: Parameters<F>): ReturnType<F> {
-    const revert = Storage.switch(snapshot);
-    try {
-      return fn.apply(this, args);
-    } finally {
-      Storage.restore(revert);
-    }
-  }
-
-  return wrap as unknown as F;
-}
diff --git a/tests/async-context.test.ts b/tests/async-context.test.ts
index f13f5ab..57a094c 100644
--- a/tests/async-context.test.ts
+++ b/tests/async-context.test.ts
@@ -20,7 +20,7 @@ function test(name: string, fn: () => void) {
     throwaway.run(null, fn);
 
     throwaway.run(null, () => {
-      AsyncContext.wrap(() => {});
+      AsyncContext.Snapshot.wrap(() => {});
 
       // Ensure we're running from a new state, which is frozen.
       fn();
@@ -95,7 +95,7 @@ describe("sync", () => {
   describe("wrap", () => {
     test("stores initial undefined state", () => {
       const ctx = new AsyncContext.Variable<Value>();
-      const wrapped = AsyncContext.wrap(() => ctx.get());
+      const wrapped = AsyncContext.Snapshot.wrap(() => ctx.get());
 
       ctx.run({ id: 1 }, () => {
         assert.equal(wrapped(), undefined);
@@ -107,7 +107,7 @@ describe("sync", () => {
       const expected = { id: 1 };
 
       const wrap = ctx.run(expected, () => {
-        const wrap = AsyncContext.wrap(() => ctx.get());
+        const wrap = AsyncContext.Snapshot.wrap(() => ctx.get());
         assert.equal(wrap(), expected);
         assert.equal(ctx.get(), expected);
         return wrap;
@@ -123,7 +123,7 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [wrap1, wrap2] = ctx.run(first, () => {
-        const wrap1 = AsyncContext.wrap(() => {
+        const wrap1 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
 
           ctx.run(second, () => {
@@ -138,7 +138,7 @@ describe("sync", () => {
           assert.equal(ctx.get(), second);
         });
 
-        const wrap2 = AsyncContext.wrap(() => {
+        const wrap2 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
 
           ctx.run(second, () => {
@@ -162,7 +162,7 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [wrap1, wrap2] = ctx.run(first, () => {
-        const wrap1 = AsyncContext.wrap(() => {
+        const wrap1 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
 
           ctx.run(second, () => {
@@ -177,7 +177,7 @@ describe("sync", () => {
           assert.equal(ctx.get(), second);
         });
 
-        const wrap2 = AsyncContext.wrap(() => {
+        const wrap2 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
 
           ctx.run(second, () => {
@@ -202,7 +202,7 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [wrap1, wrap2] = a.run(first, () => {
-        const wrap1 = AsyncContext.wrap(() => {
+        const wrap1 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(a.get(), first);
           assert.equal(b.get(), undefined);
 
@@ -217,7 +217,7 @@ describe("sync", () => {
 
         a.run(second, () => {});
 
-        const wrap2 = AsyncContext.wrap(() => {
+        const wrap2 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(a.get(), first);
           assert.equal(b.get(), undefined);
 
@@ -248,7 +248,7 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [wrap1, wrap2] = a.run(first, () => {
-        const wrap1 = AsyncContext.wrap(() => {
+        const wrap1 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(a.get(), first);
           assert.equal(b.get(), undefined);
 
@@ -263,7 +263,7 @@ describe("sync", () => {
 
         b.run(second, () => {});
 
-        const wrap2 = AsyncContext.wrap(() => {
+        const wrap2 = AsyncContext.Snapshot.wrap(() => {
           assert.equal(a.get(), first);
           assert.equal(b.get(), undefined);
 
@@ -293,13 +293,13 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [firstWrap, secondWrap] = ctx.run(first, () => {
-        const firstWrap = AsyncContext.wrap(() => {
+        const firstWrap = AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
         });
         firstWrap();
 
         const secondWrap = ctx.run(second, () => {
-          const secondWrap = AsyncContext.wrap(() => {
+          const secondWrap = AsyncContext.Snapshot.wrap(() => {
             firstWrap();
             assert.equal(ctx.get(), second);
           });
@@ -329,14 +329,14 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const [firstWrap, secondWrap] = a.run(first, () => {
-        const firstWrap = AsyncContext.wrap(() => {
+        const firstWrap = AsyncContext.Snapshot.wrap(() => {
           assert.equal(a.get(), first);
           assert.equal(b.get(), undefined);
         });
         firstWrap();
 
         const secondWrap = b.run(second, () => {
-          const secondWrap = AsyncContext.wrap(() => {
+          const secondWrap = AsyncContext.Snapshot.wrap(() => {
             firstWrap();
             assert.equal(a.get(), first);
             assert.equal(b.get(), second);
@@ -375,7 +375,7 @@ describe("sync", () => {
       const wrap = a.run(first, () => {
         const wrap = b.run(second, () => {
           const wrap = c.run(third, () => {
-            return AsyncContext.wrap(() => {
+            return AsyncContext.Snapshot.wrap(() => {
               assert.equal(a.get(), first);
               assert.equal(b.get(), second);
               assert.equal(c.get(), third);
@@ -412,10 +412,10 @@ describe("sync", () => {
 
       const wrap = a.run(first, () => {
         const wrap = b.run(second, () => {
-          AsyncContext.wrap(() => {});
+          AsyncContext.Snapshot.wrap(() => {});
 
           const wrap = c.run(third, () => {
-            return AsyncContext.wrap(() => {
+            return AsyncContext.Snapshot.wrap(() => {
               assert.equal(a.get(), first);
               assert.equal(b.get(), second);
               assert.equal(c.get(), third);
@@ -451,11 +451,11 @@ describe("sync", () => {
       const third = { id: 3 };
 
       const wrap = a.run(first, () => {
-        AsyncContext.wrap(() => {});
+        AsyncContext.Snapshot.wrap(() => {});
 
         const wrap = b.run(second, () => {
           const wrap = c.run(third, () => {
-            return AsyncContext.wrap(() => {
+            return AsyncContext.Snapshot.wrap(() => {
               assert.equal(a.get(), first);
               assert.equal(b.get(), second);
               assert.equal(c.get(), third);
@@ -493,14 +493,14 @@ describe("sync", () => {
       const wrap = a.run(first, () => {
         const wrap = b.run(second, () => {
           const wrap = c.run(third, () => {
-            return AsyncContext.wrap(() => {
+            return AsyncContext.Snapshot.wrap(() => {
               assert.equal(a.get(), first);
               assert.equal(b.get(), second);
               assert.equal(c.get(), third);
             });
           });
 
-          AsyncContext.wrap(() => {});
+          AsyncContext.Snapshot.wrap(() => {});
 
           assert.equal(a.get(), first);
           assert.equal(b.get(), second);
@@ -534,7 +534,7 @@ describe("sync", () => {
       const wrap = a.run(first, () => {
         const wrap = b.run(second, () => {
           const wrap = c.run(third, () => {
-            return AsyncContext.wrap(() => {
+            return AsyncContext.Snapshot.wrap(() => {
               assert.equal(a.get(), first);
               assert.equal(b.get(), second);
               assert.equal(c.get(), third);
@@ -546,7 +546,7 @@ describe("sync", () => {
           return wrap;
         });
 
-        AsyncContext.wrap(() => {});
+        AsyncContext.Snapshot.wrap(() => {});
 
         assert.equal(a.get(), first);
         assert.equal(b.get(), undefined);
@@ -570,12 +570,12 @@ describe("sync", () => {
       const second = { id: 2 };
 
       const firstWrap = ctx.run(first, () => {
-        return AsyncContext.wrap(() => {
+        return AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), first);
         });
       });
       const secondWrap = ctx.run(second, () => {
-        return AsyncContext.wrap(() => {
+        return AsyncContext.Snapshot.wrap(() => {
           assert.equal(ctx.get(), second);
         });
       });

From b4a83fa61ffc2701aad841b9f8bef22371169f21 Mon Sep 17 00:00:00 2001
From: Justin Ridgewell <justin@ridgewell.name>
Date: Sun, 11 Feb 2024 22:04:30 -0500
Subject: [PATCH 4/4] Fix polyfill

---
 src/promise-polyfill.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/promise-polyfill.ts b/src/promise-polyfill.ts
index 4746336..aa0d78b 100644
--- a/src/promise-polyfill.ts
+++ b/src/promise-polyfill.ts
@@ -3,10 +3,11 @@ import { AsyncContext } from "./index";
 import type { AnyFunc } from "./types";
 
 export const nativeThen = Promise.prototype.then;
+const { wrap } = AsyncContext.Snapshot;
 
 function wrapFn<F extends AnyFunc<any>>(fn: F | null | undefined) {
   if (typeof fn !== "function") return undefined;
-  return AsyncContext.wrap(fn);
+  return wrap(fn);
 }
 
 export function then<T>(