fix: support logging errors that do not contain a stack (#457)

Custom errors may not have their stack property set.
Pino used to serialize undefined stack which created invalid JSON output

pino.js

@@ -146,7 +146,8 @@ function asJson (obj, msg, num, time) {
  if (hasObj) {
  var notHasOwnProperty = obj.hasOwnProperty === undefined
  if (objError) {
- data += ',"type":"Error","stack":' + this.stringify(obj.stack)
+ data += ',"type":"Error"'
+ data += obj.stack ? ',"stack":' + this.stringify(obj.stack) : ''
  }
  // if global serializer is set, call it first
  if (this.serializers[Symbol.for('pino.*')]) {

pretty.js

@@ -217,7 +217,9 @@ function pretty (opts) {
  line += eol
 
  if (value.type === 'Error') {
- line += ' ' + withSpaces(value.stack, eol) + eol
+ line += value.stack
+ ? ' ' + withSpaces(value.stack, eol) + eol
+ : ''
 
  var propsForPrint
  if (errorProps && errorProps.length > 0) {

test/error.test.js

@@ -128,3 +128,18 @@ test('an error with statusCode property is not confused for a http response', fu
  instance.level = name
  instance[name](err)
 })
+
+test('stack is omitted if it is not set on err', t => {
+ t.plan(2)
+ var err = new Error('myerror')
+ delete err.stack
+ var instance = pino(sink(function (chunk, enc, cb) {
+ t.ok(new Date(chunk.time) <= new Date(), 'time is greater than Date.now()')
+ delete chunk.time
+ t.equal(chunk.hasOwnProperty('stack'), false)
+ cb()
+ }))
+
+ instance.level = name
+ instance[name](err)
+})

test/pretty.test.js

@@ -105,6 +105,24 @@ test('pino transform prettifies Error', function (t) {
  instance.info(err)
 })
 
+test('pino transform prettifies Error without stack', function (t) {
+ var prettier = pretty()
+ var err = new Error('hello world')
+ delete err.stack
+ var expected = [err.message]
+
+ t.plan(expected.length)
+
+ prettier.pipe(split(function (line) {
+ t.ok(line.indexOf(expected.shift()) >= 0, 'line matches')
+ return line
+ }))
+
+ var instance = pino(prettier)
+
+ instance.info(err)
+})
+
 function getIndentLevel (str) {
  return (/^\s*/.exec(str) || [''])[0].length
 }