Resolve issue #7

Readme.md

@@ -44,6 +44,8 @@ feed, to the formatted log line.
 to human readable format (see: `--translateTime`). The default format string
 is `'yyyy-mm-dd HH:MM:ss.l o'`. For a list of available patter letters
 see the [`dateformat` documentation](https://www.npmjs.com/package/dateformat).
+When the value is anything other than the default value, `--translateTime` is
+implied.
 + `--errorProps` (`-e`): When formatting an error object, display this list
 of properties. The list should be a comma separated list of properties Default: `''`.
 + `--levelFirst` (`-l`): Display the log level name before the logged date and time.

bin.js

@@ -6,15 +6,16 @@ const pump = require('pump')
 const split = require('split2')
 const through = require('through2')
 const prettyFactory = require('./')
+const CONSTANTS = require('./lib/constants')
 
 args
   .option(['c', 'colorize'], 'Force adding color sequences to the output')
   .option(['f', 'crlf'], 'Append CRLF instead of LF to formatted lines')
-  .option(['d', 'dateFormat'], 'A format string to govern display of dates', 'yyyy-MM-dd HH:mm:ss.SSS Z')
+  .option(['d', 'dateFormat'], 'A format string to govern display of dates. When not set to the default value, `--translateTime` is implied', CONSTANTS.DATE_FORMAT)
   .option(['e', 'errorProps'], 'Comma separated list of properties on error objects to show (`*` for all properties)', '')
   .option(['l', 'levelFirst'], 'Display the log level as the first output field')
   .option(['k', 'errorLikeObjectKeys'], 'Define which keys contain error objects (`-k err,error`)', 'err,error')
-  .option(['m', 'messageKey'], 'Highlight the message under the specified key', 'msg')
+  .option(['m', 'messageKey'], 'Highlight the message under the specified key', CONSTANTS.MESSAGE_KEY)
   .option(['n', 'localTime'], 'Display timestamps according to system timezone')
   .option(['t', 'translateTime'], 'Convert Epoch timestamps to ISO format')
 

index.js

@@ -4,6 +4,8 @@ const chalk = require('chalk')
 const dateformat = require('dateformat')
 const jsonParser = require('fast-json-parse')
 
+const CONSTANTS = require('./lib/constants')
+
 const levels = {
   default: 'USERLVL',
   60: 'FATAL',
@@ -17,12 +19,12 @@ const levels = {
 const defaultOptions = {
   colorize: false,
   crlf: false,
-  dateFormat: 'yyyy-mm-dd HH:MM:ss.l o',
+  dateFormat: CONSTANTS.DATE_FORMAT,
   errorLikeObjectKeys: ['err', 'error'],
   errorProps: '',
   levelFirst: false,
   localTime: false,
-  messageKey: 'msg',
+  messageKey: CONSTANTS.MESSAGE_KEY,
   translateTime: false,
   useMetadata: false,
   outputStream: process.stdout
@@ -54,6 +56,10 @@ module.exports = function prettyFactory (options) {
   const errorLikeObjectKeys = opts.errorLikeObjectKeys
   const errorProps = opts.errorProps.split(',')
 
+  if (opts.dateFormat.length > 0 && opts.dateFormat !== CONSTANTS.DATE_FORMAT) {
+    opts.translateTime = true
+  }
+
   const color = {
     default: nocolor,
     60: nocolor,

lib/constants.js

@@ -0,0 +1,6 @@
+'use strict'
+
+module.exports = {
+  DATE_FORMAT: 'yyyy-mm-dd HH:MM:ss.l o',
+  MESSAGE_KEY: 'msg'
+}

test/basic.test.js

@@ -137,10 +137,7 @@ test('basic prettifier tests', (t) => {
 
   t.test('will format date with a custom format string', (t) => {
     t.plan(1)
-    const pretty = prettyFactory({
-      translateTime: true,
-      dateFormat: 'yyyy-mm-dd HH:MM'
-    })
+    const pretty = prettyFactory({dateFormat: 'yyyy-mm-dd HH:MM'})
     const log = pino({}, new Writable({
       write (chunk, enc, cb) {
         const formatted = pretty(chunk.toString())

test/cli.test.js

@@ -31,5 +31,16 @@ test('cli', (t) => {
     t.tearDown(() => child.kill())
   })
 
+  t.test('translates time to default format', (t) => {
+    t.plan(1)
+    const child = spawn(process.argv0, [bin, '-t'])
+    child.on('error', t.threw)
+    child.stdout.on('data', (data) => {
+      t.is(data.toString(), `[2018-03-30 17:35:28.992 +0000] INFO (42 on foo): hello world\n`)
+    })
+    child.stdin.write(logLine)
+    t.tearDown(() => child.kill())
+  })
+
   t.end()
 })