Store the resource in a WeakRef to avoid keeping a reference (#87)

Closes #84

Co-authored-by: Jon Koops <jonkoops@gmail.com>

Author: betalb

index.js

@@ -21,7 +21,7 @@ const hook = createHook({
 
     asyncResources.set(asyncId, {
       type,
-      resource,
+      resourceRef: new WeakRef(resource),
       stacks
     })
   },
@@ -36,7 +36,15 @@ export default function whyIsNodeRunning (logger = console) {
   hook.disable()
 
   const activeAsyncResources = Array.from(asyncResources.values())
-    .filter(({ resource }) => resource.hasRef?.() ?? true)
+    .filter(({ resourceRef }) => {
+      const resource = resourceRef.deref()
+
+      if (resource === undefined) {
+        return false
+      }
+  
+      return resource.hasRef?.() ?? true
+    })
 
   logger.error(`There are ${activeAsyncResources.length} handle(s) keeping the process running.`)
 
@@ -47,7 +55,7 @@ export default function whyIsNodeRunning (logger = console) {
 
 function printStacks (asyncResource, logger) {
   const stacks = asyncResource.stacks.filter((stack) => {
-    const fileName = stack.getFileName()
+    const fileName = stack.fileName
     return fileName !== null && !fileName.startsWith('node:')
   })
 
@@ -66,8 +74,8 @@ function printStacks (asyncResource, logger) {
     const padding = ' '.repeat(maxLength - location.length)
 
     try {
-      const lines = readFileSync(normalizeFilePath(stack.getFileName()), 'utf-8').split(/\n|\r\n/)
-      const line = lines[stack.getLineNumber() - 1].trim()
+      const lines = readFileSync(normalizeFilePath(stack.fileName), 'utf-8').split(/\n|\r\n/)
+      const line = lines[stack.lineNumber - 1].trim()
 
       logger.error(`${location}${padding} - ${line}`)
     } catch (e) {
@@ -77,8 +85,8 @@ function printStacks (asyncResource, logger) {
 }
 
 function formatLocation (stack) {
-  const filePath = formatFilePath(stack.getFileName())
-  return `${filePath}:${stack.getLineNumber()}`
+  const filePath = formatFilePath(stack.fileName)
+  return `${filePath}:${stack.lineNumber}`
 }
 
 function formatFilePath (filePath) {
@@ -92,12 +100,19 @@ function normalizeFilePath (filePath) {
   return filePath.startsWith('file://') ? fileURLToPath(filePath) : filePath
 }
 
+function prepareStackTrace(error, stackTraces) {
+  return stackTraces.map(stack => ({
+    lineNumber: stack.getLineNumber(),
+    fileName: stack.getFileName()
+  }))
+}
+
 // See: https://v8.dev/docs/stack-trace-api
 function captureStackTraces () {
   const target = {}
   const original = Error.prepareStackTrace
 
-  Error.prepareStackTrace = (error, stackTraces) => stackTraces
+  Error.prepareStackTrace = prepareStackTrace
   Error.captureStackTrace(target, captureStackTraces)
 
   const capturedTraces = target.stack