add hw2

node_modules/pino-std-serializers/lib/err-with-cause.js

@@ -0,0 +1,48 @@
+'use strict'
+
+module.exports = errWithCauseSerializer
+
+const { isErrorLike } = require('./err-helpers')
+const { pinoErrProto, pinoErrorSymbols } = require('./err-proto')
+const { seen } = pinoErrorSymbols
+
+const { toString } = Object.prototype
+
+function errWithCauseSerializer (err) {
+  if (!isErrorLike(err)) {
+    return err
+  }
+
+  err[seen] = undefined // tag to prevent re-looking at this
+  const _err = Object.create(pinoErrProto)
+  _err.type = toString.call(err.constructor) === '[object Function]'
+    ? err.constructor.name
+    : err.name
+  _err.message = err.message
+  _err.stack = err.stack
+
+  if (Array.isArray(err.errors)) {
+    _err.aggregateErrors = err.errors.map(err => errWithCauseSerializer(err))
+  }
+
+  if (isErrorLike(err.cause) && !Object.prototype.hasOwnProperty.call(err.cause, seen)) {
+    _err.cause = errWithCauseSerializer(err.cause)
+  }
+
+  for (const key in err) {
+    if (_err[key] === undefined) {
+      const val = err[key]
+      if (isErrorLike(val)) {
+        if (!Object.prototype.hasOwnProperty.call(val, seen)) {
+          _err[key] = errWithCauseSerializer(val)
+        }
+      } else {
+        _err[key] = val
+      }
+    }
+  }
+
+  delete err[seen] // clean up tag in case err is serialized again later
+  _err.raw = err
+  return _err
+}