Fix bug where multiple copies of logger breaks logging errors (webdri…

…verio#4785)

* Reproduce bug where we replace method factory more than once

* Source 2nd copy of code instead from build dir

* Use the extra logger to make the no-unused-vars rule happy

* Only extend methodFactory if it's the first time

* Explicitly copy the source, rather than relying on the compile step to do it

* Exclude build dir from coverage, go back to using it as 2nd source

* Switch to solution with fewest non-whitespace changes

* Prefix children rather than root logger

package.json

@@ -124,7 +124,8 @@
       "packages/wdio-devtools-service/src/scripts",
       "packages/webdriverio/build",
       "packages/webdriver/build",
-      "packages/wdio-cucumber-framework/tests/fixtures"
+      "packages/wdio-cucumber-framework/tests/fixtures",
+      "packages/wdio-logger/build"
     ]
   },
   "greenkeeper": {

packages/wdio-logger/src/node.js

@@ -48,13 +48,13 @@ const SERIALIZERS = [{
     serialize: (log) => chalk.cyan(log)
 }]
 
-const loggers = {}
+const loggers = log.getLoggers()
 let logLevelsConfig = {}
 const logCache = new Set()
 let logFile
 
 const originalFactory = log.methodFactory
-log.methodFactory = function (methodName, logLevel, loggerName) {
+const wdioLoggerMethodFactory = function (methodName, logLevel, loggerName) {
     const rawMethod = originalFactory(methodName, logLevel, loggerName)
     return (...args) => {
         /**
@@ -101,13 +101,6 @@ log.methodFactory = function (methodName, logLevel, loggerName) {
     }
 }
 
-prefix.apply(log, {
-    template: '%t %l %n:',
-    timestampFormatter: (date) => chalk.gray(date.toISOString()),
-    levelFormatter: (level) => chalk[COLORS[level]](level.toUpperCase()),
-    nameFormatter: (name) => chalk.whiteBright(name)
-})
-
 export default function getLogger (name) {
     /**
      * check if logger was already initiated
@@ -124,6 +117,13 @@ export default function getLogger (name) {
 
     loggers[name] = log.getLogger(name)
     loggers[name].setLevel(logLevel)
+    loggers[name].methodFactory = wdioLoggerMethodFactory
+    prefix.apply(loggers[name], {
+        template: '%t %l %n:',
+        timestampFormatter: (date) => chalk.gray(date.toISOString()),
+        levelFormatter: (level) => chalk[COLORS[level]](level.toUpperCase()),
+        nameFormatter: (name) => chalk.whiteBright(name)
+    })
     return loggers[name]
 }
 /**

packages/wdio-logger/tests/node.test.js

@@ -1,5 +1,6 @@
 import fs from 'fs'
 import nodeLogger from '../src/node'
+import nodeLogger2 from '../build/node'
 
 describe('wdio-logger node', () => {
     describe('log level', () => {
@@ -200,6 +201,19 @@ describe('wdio-logger node', () => {
             expect(write.mock.results[3].value).toContain('test-logFile4: Error: bar')
         })
 
+        it('is not confused by multiple copies of source code', () => {
+            process.env.WDIO_LOG_PATH = 'wdio.test.log'
+
+            const log = nodeLogger('test-logFile4')
+            const log2 = nodeLogger2('test-logFile4')
+            log.info('foo')
+            log2.error(new Error('bar'))
+
+            expect(write.mock.calls.length).toBe(2)
+            expect(write.mock.results[0].value).toContain('test-logFile4: foo')
+            expect(write.mock.results[1].value).toContain('test-logFile4: Error: bar')
+        })
+
         describe('waitForBuffer with logFile', () => {
             const scenarios = [{
                 name: 'should be ok buffer is empty',