From d238566139ae53d64906d3d6c68ceeb7407fe44d Mon Sep 17 00:00:00 2001
From: Matteo Collina <hello@matteocollina.com>
Date: Fri, 19 Apr 2024 17:28:45 +0200
Subject: [PATCH] automatic start

Signed-off-by: Matteo Collina <hello@matteocollina.com>
---
 asyncforge.js                  | 10 ++++--
 test/basic.test.js             | 12 +++++++
 test/do-not-start-memo.test.js | 64 ++++++++++++++++++++++++++++++++++
 test/fixture/basic/a.js        |  2 +-
 4 files changed, 84 insertions(+), 4 deletions(-)
 create mode 100644 test/do-not-start-memo.test.js

diff --git a/asyncforge.js b/asyncforge.js
index 28863cd..647df1c 100644
--- a/asyncforge.js
+++ b/asyncforge.js
@@ -14,7 +14,11 @@ let forgeCounter = 0
 function forge (fn) {
   const sym = Symbol('forge.' + (fn.name || forgeCounter++))
   return function () {
-    const store = asyncLocalStorage.getStore()
+    let store = asyncLocalStorage.getStore()
+    if (!store) {
+      store = Object.create(null)
+      asyncLocalStorage.enterWith(store)
+    }
     if (store[sym]) {
       return store[sym]
     }
@@ -32,12 +36,12 @@ function memo (name) {
 
   function get () {
     const store = asyncLocalStorage.getStore()
-    return store[sym]
+    return store?.[sym]
   }
 
   function set (value) {
     let store = asyncLocalStorage.getStore()
-    store = Object.create(store)
+    store = Object.create(store || null)
     store[sym] = value
     asyncLocalStorage.enterWith(store)
   }
diff --git a/test/basic.test.js b/test/basic.test.js
index 2b35e23..c85a0ab 100644
--- a/test/basic.test.js
+++ b/test/basic.test.js
@@ -6,6 +6,18 @@ const { start, forge } = require('../')
 const { setImmediate: immediate } = require('node:timers/promises')
 const tspl = require('@matteo.collina/tspl')
 
+test('forge', async (t) => {
+  const { a, b } = require('./fixture/basic')
+
+  assert.deepEqual(a(), { value: undefined })
+  assert.equal(a(), a())
+  assert.deepEqual(b(), {
+    fromA: {
+      value: undefined
+    }
+  })
+})
+
 test('start and forge', async (t) => {
   const { a, b } = require('./fixture/basic')
 
diff --git a/test/do-not-start-memo.test.js b/test/do-not-start-memo.test.js
new file mode 100644
index 0000000..13e6c52
--- /dev/null
+++ b/test/do-not-start-memo.test.js
@@ -0,0 +1,64 @@
+'use strict'
+
+const { test } = require('node:test')
+const { start, memo } = require('../')
+const tspl = require('@matteo.collina/tspl')
+
+test('memo without start', async (t) => {
+  const p = tspl(t, { plan: 6 })
+  const a = memo()
+
+  p.deepStrictEqual(a(), undefined)
+  a.set({ value: 'bar' })
+  p.deepStrictEqual(a(), { value: 'bar' })
+
+  setImmediate(() => {
+    p.deepStrictEqual(a(), { value: 'bar' })
+  })
+
+  queueMicrotask(() => {
+    p.deepStrictEqual(a(), { value: 'bar' })
+  })
+
+  start()
+
+  p.deepStrictEqual(a(), undefined)
+  a.set({ value: 'baz' })
+
+  p.deepEqual(a(), { value: 'baz' })
+
+  setImmediate(() => {
+    p.deepStrictEqual(a(), { value: 'baz' })
+  })
+
+  queueMicrotask(() => {
+    p.deepStrictEqual(a(), { value: 'baz' })
+  })
+
+  await p.completed
+})
+
+test('nested', async (t) => {
+  const p = tspl(t, { plan: 5 })
+  const a = memo()
+
+  p.deepStrictEqual(a(), undefined)
+  a.set({ value: 'bar' })
+  p.deepStrictEqual(a(), { value: 'bar' })
+
+  setImmediate(() => {
+    p.deepStrictEqual(a(), { value: 'bar' })
+
+    a.set({ value: 'baz' })
+
+    setImmediate(() => {
+      p.deepStrictEqual(a(), { value: 'baz' })
+    })
+  })
+
+  setImmediate(() => {
+    p.deepStrictEqual(a(), { value: 'bar' })
+  })
+
+  await p.completed
+})
diff --git a/test/fixture/basic/a.js b/test/fixture/basic/a.js
index fe730ff..9191176 100644
--- a/test/fixture/basic/a.js
+++ b/test/fixture/basic/a.js
@@ -4,6 +4,6 @@ const { forge } = require('../../../')
 
 module.exports = forge((config) => {
   return {
-    value: config.foo
+    value: config?.foo
   }
 })