From a92c6d80107a87e9c8de672e07d45cbfc25b7465 Mon Sep 17 00:00:00 2001
From: Manuel Spigolon <manuel.spigolon@nearform.com>
Date: Sat, 18 Nov 2023 09:56:19 +0100
Subject: [PATCH 1/2] fix: avoid global unlimited config

---
 index.js                    | 21 +++++++++++++++------
 test/emit-once-only.test.js |  2 +-
 test/issue-88.test.js       | 26 ++++++++++++++++++++++++++
 3 files changed, 42 insertions(+), 7 deletions(-)
 create mode 100644 test/issue-88.test.js

diff --git a/index.js b/index.js
index 1e7f87f..5919c8c 100644
--- a/index.js
+++ b/index.js
@@ -43,7 +43,6 @@ const { format } = require('node:util')
 function processWarning () {
   const codes = {}
   const emitted = new Map()
-  const opts = Object.create(null)
 
   /**
    * Builds a new {@link ProcessWarning} and adds it to the
@@ -91,8 +90,12 @@ function processWarning () {
       }
     }
 
-    Object.assign(opts, { unlimited })
-    emitted.set(code, unlimited)
+    // We need to manage 4 states:
+    // - START: code 0: unlimited emission
+    // - END: code -1: unlimited event emitted
+    // - START: code 1 (default): limited emission to 1
+    // - END: code 2: limited event emitted
+    emitted.set(code, unlimited ? 0 : 1)
     codes[code] = buildWarnOpts
 
     return codes[code]
@@ -137,9 +140,10 @@ function processWarning () {
    * @param {*} [c] Possible message interpolation value.
    */
   function emit (code, a, b, c) {
-    if (emitted.get(code) === true && opts.unlimited === false) return
+    const state = emitted.get(code)
+    if (state === 2) return
     if (codes[code] === undefined) throw new Error(`The code '${code}' does not exist`)
-    emitted.set(code, true)
+    emitted.set(code, state <= 0 ? -1 : (state + 1))
 
     const warning = codes[code](a, b, c)
     process.emitWarning(warning.message, warning.name, warning.code)
@@ -149,7 +153,12 @@ function processWarning () {
     create,
     createDeprecation,
     emit,
-    emitted
+    emitted: {
+      get (code) {
+        const state = emitted.get(code)
+        return state === -1 || state === 2
+      }
+    }
   }
 }
 
diff --git a/test/emit-once-only.test.js b/test/emit-once-only.test.js
index e1d8a30..75d9036 100644
--- a/test/emit-once-only.test.js
+++ b/test/emit-once-only.test.js
@@ -1,6 +1,6 @@
 'use strict'
 
-const test = require('tap').test
+const { test } = require('tap')
 const build = require('..')
 
 test('emit should emit a given code only once', t => {
diff --git a/test/issue-88.test.js b/test/issue-88.test.js
new file mode 100644
index 0000000..79696c0
--- /dev/null
+++ b/test/issue-88.test.js
@@ -0,0 +1,26 @@
+'use strict'
+
+const { test } = require('tap')
+const build = require('..')
+
+test('Must not overwrite the global config', t => {
+  t.plan(1)
+
+  const { create, emit } = build()
+
+  function onWarning (warning) {
+    t.equal(warning.code, 'CODE_1')
+  }
+
+  create('FastifyWarning', 'CODE_1', 'Msg', { unlimited: false })
+  create('FastifyWarning', 'CODE_2', 'Msg', { unlimited: true })
+
+  process.on('warning', onWarning)
+  emit('CODE_1')
+  emit('CODE_1')
+
+  setImmediate(() => {
+    process.removeListener('warning', onWarning)
+    t.end()
+  })
+})

From 7fb42e43bde5ebbf69e97d97412c885477f57a71 Mon Sep 17 00:00:00 2001
From: Manuel Spigolon <manuel.spigolon@nearform.com>
Date: Sat, 18 Nov 2023 10:18:08 +0100
Subject: [PATCH 2/2] chore: add bench script

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 471d34c..f886dd2 100644
--- a/package.json
+++ b/package.json
@@ -8,6 +8,7 @@
   "scripts": {
     "lint": "standard",
     "lint:fix": "standard --fix",
+    "benchmark": "node benchmarks/warn.js",
     "test": "npm run test:unit && npm run test:jest && npm run test:typescript",
     "test:jest": "jest jest.test.js",
     "test:unit": "tap",