First commit

node_modules/on-exit-leak-free/index.js

@@ -0,0 +1,108 @@
+'use strict'
+
+const refs = {
+  exit: [],
+  beforeExit: []
+}
+const functions = {
+  exit: onExit,
+  beforeExit: onBeforeExit
+}
+
+let registry
+
+function ensureRegistry () {
+  if (registry === undefined) {
+    registry = new FinalizationRegistry(clear)
+  }
+}
+
+function install (event) {
+  if (refs[event].length > 0) {
+    return
+  }
+
+  process.on(event, functions[event])
+}
+
+function uninstall (event) {
+  if (refs[event].length > 0) {
+    return
+  }
+  process.removeListener(event, functions[event])
+  if (refs.exit.length === 0 && refs.beforeExit.length === 0) {
+    registry = undefined
+  }
+}
+
+function onExit () {
+  callRefs('exit')
+}
+
+function onBeforeExit () {
+  callRefs('beforeExit')
+}
+
+function callRefs (event) {
+  for (const ref of refs[event]) {
+    const obj = ref.deref()
+    const fn = ref.fn
+
+    // This should always happen, however GC is
+    // undeterministic so it might not happen.
+    /* istanbul ignore else */
+    if (obj !== undefined) {
+      fn(obj, event)
+    }
+  }
+  refs[event] = []
+}
+
+function clear (ref) {
+  for (const event of ['exit', 'beforeExit']) {
+    const index = refs[event].indexOf(ref)
+    refs[event].splice(index, index + 1)
+    uninstall(event)
+  }
+}
+
+function _register (event, obj, fn) {
+  if (obj === undefined) {
+    throw new Error('the object can\'t be undefined')
+  }
+  install(event)
+  const ref = new WeakRef(obj)
+  ref.fn = fn
+
+  ensureRegistry()
+  registry.register(obj, ref)
+  refs[event].push(ref)
+}
+
+function register (obj, fn) {
+  _register('exit', obj, fn)
+}
+
+function registerBeforeExit (obj, fn) {
+  _register('beforeExit', obj, fn)
+}
+
+function unregister (obj) {
+  if (registry === undefined) {
+    return
+  }
+  registry.unregister(obj)
+  for (const event of ['exit', 'beforeExit']) {
+    refs[event] = refs[event].filter((ref) => {
+      const _obj = ref.deref()
+      return _obj && _obj !== obj
+    })
+    uninstall(event)
+  }
+}
+
+module.exports = {
+  register,
+  registerBeforeExit,
+  unregister
+}