refactor(server): use ES6 string interpolation wherever possible

lib/cli.js

@@ -15,7 +15,7 @@ function processArgs (argv, options, fs, path) {
   }
 
   if (argv.version) {
-    console.log('Karma version: ' + constant.VERSION)
+    console.log(`Karma version: ${constant.VERSION}`)
     process.exit(0)
   }
 
@@ -24,7 +24,7 @@ function processArgs (argv, options, fs, path) {
     let argumentValue = argv[name]
     if (name !== '_' && name !== '$0') {
       if (name.includes('_')) {
-        throw new Error('Bad argument: ' + name + ' did you mean ' + name.replace('_', '-'))
+        throw new Error(`Bad argument: ${name} did you mean ${name.replace('_', '-')}`)
       }
       if (Array.isArray(argumentValue)) {
         // If the same argument is defined multiple times, override.
@@ -60,7 +60,7 @@ function processArgs (argv, options, fs, path) {
     // support exports.formatError and module.exports = function
     options.formatError = required.formatError || required
     if (!helper.isFunction(options.formatError)) {
-      console.error('Format error must be a function, got: ' + typeof options.formatError)
+      console.error(`Format error must be a function, got: ${typeof options.formatError}`)
       process.exit(1)
     }
   }

lib/completion.js

@@ -35,11 +35,11 @@ const options = {
 }
 
 function opositeWord (word) {
-  if (!word.startsWith('-')) {
+  if (word.startsWith('-')) {
+    return word.startsWith('--no-') ? `--${word.substr(5)}` : `--no-${word.substr(2)}`
+  } else {
     return null
   }
-
-  return word.substr(0, 5) === '--no-' ? '--' + word.substr(5) : '--no-' + word.substr(2)
 }
 
 function sendCompletion (possibleWords, env) {

lib/config.js

@@ -234,7 +234,7 @@ function normalizeConfig (config, configFilePath) {
   const types = ['launcher', 'preprocessor', 'reporter']
 
   types.forEach(function (type) {
-    const definitions = config['custom' + helper.ucFirst(type) + 's'] || {}
+    const definitions = config[`custom${helper.ucFirst(type)}s`] || {}
 
     Object.keys(definitions).forEach(function (name) {
       const definition = definitions[name]

lib/file-list.js

@@ -80,13 +80,13 @@ class FileList {
       const files = mg.found
       if (_.isEmpty(files)) {
         this.buckets.set(pattern, [])
-        log.warn('Pattern "%s" does not match any file.', pattern)
+        log.warn(`Pattern "${pattern}" does not match any file.`)
         return
       }
 
       return Promise.map(files, (path) => {
         if (this._findExcluded(path)) {
-          log.debug('Excluded file "%s"', path)
+          log.debug(`Excluded file "${path}"`)
           return Promise.resolve()
         }
 
@@ -98,7 +98,7 @@ class FileList {
 
         const file = new File(path, mg.statCache[path].mtime, patternObject.nocache, type)
         if (file.doNotCache) {
-          log.debug('Not preprocessing "%s" due to nocache', pattern)
+          log.debug(`Not preprocessing "${pattern}" due to nocache`)
           return Promise.resolve(file)
         }
 
@@ -109,7 +109,7 @@ class FileList {
           this.buckets.set(pattern, files)
 
           if (_.isEmpty(files)) {
-            log.warn('All files matched by "%s" were excluded or matched by prior matchers.', pattern)
+            log.warn(`All files matched by "${pattern}" were excluded or matched by prior matchers.`)
           }
         })
     })
@@ -180,18 +180,18 @@ class FileList {
   addFile (path) {
     const excluded = this._findExcluded(path)
     if (excluded) {
-      log.debug('Add file "%s" ignored. Excluded by "%s".', path, excluded)
+      log.debug(`Add file "${path}" ignored. Excluded by "${excluded}".`)
       return Promise.resolve(this.files)
     }
 
     const pattern = this._findIncluded(path)
     if (!pattern) {
-      log.debug('Add file "%s" ignored. Does not match any pattern.', path)
+      log.debug(`Add file "${path}" ignored. Does not match any pattern.`)
       return Promise.resolve(this.files)
     }
 
     if (this._exists(path)) {
-      log.debug('Add file "%s" ignored. Already in the list.', path)
+      log.debug(`Add file "${path}" ignored. Already in the list.`)
       return Promise.resolve(this.files)
     }
 
@@ -207,7 +207,7 @@ class FileList {
         return this._preprocess(file)
       })
       .then(() => {
-        log.info('Added file "%s".', path)
+        log.info(`Added file "${path}".`)
         this._emitModified()
         return this.files
       })
@@ -218,7 +218,7 @@ class FileList {
     const file = this._findFile(path, pattern)
 
     if (!file) {
-      log.debug('Changed file "%s" ignored. Does not match any file in the list.', path)
+      log.debug(`Changed file "${path}" ignored. Does not match any file in the list.`)
       return Promise.resolve(this.files)
     }
 
@@ -232,7 +232,7 @@ class FileList {
       return this._preprocess(file)
     })
       .then(() => {
-        log.info('Changed file "%s".', path)
+        log.info(`Changed file "${path}".`)
         this._emitModified(force)
         return this.files
       })
@@ -246,11 +246,11 @@ class FileList {
 
       if (file) {
         helper.arrayRemove(this._getFilesByPattern(pattern.pattern), file)
-        log.info('Removed file "%s".', path)
+        log.info(`Removed file "${path}".`)
 
         this._emitModified()
       } else {
-        log.debug('Removed file "%s" ignored. Does not match any file in the list.', path)
+        log.debug(`Removed file "${path}" ignored. Does not match any file in the list.`)
       }
       return this.files
     })

lib/init.js

@@ -36,26 +36,24 @@ function installPackage (pkgName) {
     return
   } catch (e) {}
 
-  log.debug('Missing plugin "%s". Installing...', pkgName)
+  log.debug(`Missing plugin "${pkgName}". Installing...`)
 
   const options = {
     cwd: path.resolve(NODE_MODULES_DIR, '..')
   }
 
-  exec('npm install ' + pkgName + ' --save-dev', options, function (err, stdout, stderr) {
+  exec(`npm install ${pkgName} --save-dev`, options, function (err, stdout, stderr) {
     // Put the logs into the queue and print them after answering current question.
     // Otherwise the log would clobber the interactive terminal.
     logQueue.push(function () {
       if (!err) {
-        log.debug('%s successfully installed.', pkgName)
+        log.debug(`${pkgName} successfully installed.`)
       } else if (/is not in the npm registry/.test(stderr)) {
-        log.warn('Failed to install "%s". It is not in the NPM registry!\n' +
-          '  Please install it manually.', pkgName)
+        log.warn(`Failed to install "${pkgName}". It is not in the NPM registry!\n  Please install it manually.`)
       } else if (/Error: EACCES/.test(stderr)) {
-        log.warn('Failed to install "%s". No permissions to write in %s!\n' +
-          '  Please install it manually.', pkgName, options.cwd)
+        log.warn(`Failed to install "${pkgName}". No permissions to write in ${options.cwd}!\n  Please install it manually.`)
       } else {
-        log.warn('Failed to install "%s"\n  Please install it manually.', pkgName)
+        log.warn(`Failed to install "${pkgName}"\n  Please install it manually.`)
       }
     })
   })
@@ -91,8 +89,7 @@ var questions = [{
 }, {
   id: 'requirejs',
   question: 'Do you want to use Require.js ?',
-  hint: 'This will add Require.js plugin.\n' +
-    'Press tab to list possible options. Enter to move to the next question.',
+  hint: 'This will add Require.js plugin.\nPress tab to list possible options. Enter to move to the next question.',
   options: ['no', 'yes'],
   validate: validateRequireJs,
   boolean: true
@@ -106,15 +103,13 @@ var questions = [{
 }, {
   id: 'files',
   question: 'What is the location of your source and test files ?',
-  hint: 'You can use glob patterns, eg. "js/*.js" or "test/**/*Spec.js".\n' +
-    'Enter empty string to move to the next question.',
+  hint: 'You can use glob patterns, eg. "js/*.js" or "test/**/*Spec.js".\nEnter empty string to move to the next question.',
   multiple: true,
   validate: validatePattern
 }, {
   id: 'exclude',
   question: 'Should any of the files included by the previous patterns be excluded ?',
-  hint: 'You can use glob patterns, eg. "**/*.swp".\n' +
-    'Enter empty string to move to the next question.',
+  hint: 'You can use glob patterns, eg. "**/*.swp".\nEnter empty string to move to the next question.',
   multiple: true,
   validate: validatePattern
 }, {
@@ -126,7 +121,7 @@ var questions = [{
   condition: (answers) => answers.requirejs
 }, {
   id: 'includedFiles',
-  question: 'Which files do you want to include with <script> tag ?',
+  question: `Which files do you want to include with <script> tag ?`,
   hint: 'This should be a script that bootstraps your test by configuring Require.js and ' +
     'kicking __karma__.start(), probably your test-main.js file.\n' +
     'Enter empty string to move to the next question.',
@@ -235,12 +230,10 @@ exports.init = function (config) {
 
     if (processedAnswers.generateTestMain) {
       formatter.writeRequirejsConfigFile(testMainFilePath)
-      console.log(colorScheme.success(
-        'RequireJS bootstrap file generated at "' + testMainFilePath + '".\n'
-      ))
+      console.log(colorScheme.success(`RequireJS bootstrap file generated at "${testMainFilePath}".`))
     }
 
     formatter.writeConfigFile(configFilePath, processedAnswers)
-    console.log(colorScheme.success('Config file generated at "' + configFilePath + '".\n'))
+    console.log(colorScheme.success(`Config file generated at "${configFilePath}".`))
   })
 }

lib/launcher.js

@@ -91,12 +91,7 @@ function Launcher (server, emitter, injector) {
   }
 
   this.launch = (names, concurrency) => {
-    log.info(
-      'Launching browser%s %s with %s',
-      names.length > 1 ? 's' : '',
-      names.join(', '),
-      concurrency === Infinity ? 'unlimited concurrency' : `concurrency ${concurrency}`
-    )
+    log.info(`Launching browsers ${names.join(', ')} with concurrency ${concurrency === Infinity ? 'unlimited' : concurrency}`)
     this.jobs = new Jobs({ maxConcurrency: concurrency })
 
     lastStartTime = Date.now()

lib/launchers/base.js

@@ -79,7 +79,7 @@ function BaseLauncher (id, emitter) {
         this.state = FINISHED
       } else {
         killingPromise = null
-        log.debug('Restarting %s', this.name)
+        log.debug(`Restarting ${this.name}`)
         this.start(previousUrl)
       }
     })

lib/launchers/capture_timeout.js

@@ -17,7 +17,7 @@ function CaptureTimeoutLauncher (timer, captureTimeout) {
         return
       }
 
-      log.warn('%s have not captured in %d ms, killing.', this.name, captureTimeout)
+      log.warn(`${this.name} have not captured in ${captureTimeout} ms, killing.`)
       this.error = 'timeout'
       this.kill()
     }, captureTimeout)

lib/launchers/process.js

@@ -12,7 +12,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
     stderr: ''
   }
 
-  this._tempDir = tempDir.getPath('/karma-' + this.id.toString())
+  this._tempDir = tempDir.getPath(`/karma-${this.id.toString()}`)
 
   this.on('start', function (url) {
     tempDir.create(self._tempDir)
@@ -45,7 +45,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
   this._normalizeCommand = function (cmd) {
     if (cmd.charAt(0) === cmd.charAt(cmd.length - 1) && '\'`"'.includes(cmd.charAt(0))) {
       cmd = cmd.substring(1, cmd.length - 1)
-      log.warn('The path should not be quoted.\n  Normalized the path to %s', cmd)
+      log.warn(`The path should not be quoted.\n  Normalized the path to ${cmd}`)
     }
 
     return path.normalize(cmd)
@@ -61,8 +61,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
 
   this._execCommand = function (cmd, args) {
     if (!cmd) {
-      log.error('No binary for %s browser on your platform.\n  ' +
-        'Please, set "%s" env variable.', self.name, self.ENV_CMD)
+      log.error(`No binary for ${self.name} browser on your platform.\n  Please, set "${self.ENV_CMD}" env variable.`)
 
       // disable restarting
       self._retryLimit = -1
@@ -87,8 +86,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
     self._process.on('error', function (err) {
       if (err.code === 'ENOENT') {
         self._retryLimit = -1
-        errorOutput = 'Can not find the binary ' + cmd + '\n\t' +
-          'Please set env variable ' + self.ENV_CMD
+        errorOutput = `Can not find the binary ${cmd}\n\tPlease set env variable ${self.ENV_CMD}`
       } else {
         errorOutput += err.toString()
       }
@@ -100,23 +98,23 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
   }
 
   this._onProcessExit = function (code, errorOutput) {
-    log.debug('Process %s exited with code %d', self.name, code)
+    log.debug(`Process ${self.name} exited with code ${code}`)
 
     let error = null
 
     if (self.state === self.STATE_BEING_CAPTURED) {
-      log.error('Cannot start %s\n\t%s', self.name, errorOutput)
+      log.error(`Cannot start ${self.name}\n\t${errorOutput}`)
       error = 'cannot start'
     }
 
     if (self.state === self.STATE_CAPTURED) {
-      log.error('%s crashed.\n\t%s', self.name, errorOutput)
+      log.error(`${self.name} crashed.\n\t${errorOutput}`)
       error = 'crashed'
     }
 
     if (error) {
-      log.error('%s stdout: %s', self.name, streamedOutputs.stdout)
-      log.error('%s stderr: %s', self.name, streamedOutputs.stderr)
+      log.error(`${self.name} stdout: ${streamedOutputs.stdout}`)
+      log.error(`${self.name} stderr: ${streamedOutputs.stderr}`)
     }
 
     self._process = null
@@ -144,7 +142,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
       return
     }
 
-    log.warn('%s was not killed in %d ms, sending SIGKILL.', self.name, killTimeout)
+    log.warn(`${self.name} was not killed in ${killTimeout} ms, sending SIGKILL.`)
     self._process.kill('SIGKILL')
 
     // NOTE: https://github.com/karma-runner/karma/pull/1184
@@ -154,7 +152,7 @@ function ProcessLauncher (spawn, tempDir, timer, processKillTimeout) {
     // This a certainly suboptimal, but it is better than having the test harness hang waiting
     // for a zombie child process to exit.
     self._killTimer = timer.setTimeout(function () {
-      log.warn('%s was not killed by SIGKILL in %d ms, continuing.', self.name, killTimeout)
+      log.warn(`${self.name} was not killed by SIGKILL in ${killTimeout} ms, continuing.`)
       self._onProcessExit(-1, '')
     }, killTimeout)
   }

lib/launchers/retry.js

@@ -9,14 +9,13 @@ function RetryLauncher (retryLimit) {
     }
 
     if (this._retryLimit > 0) {
-      const attempt = retryLimit - this._retryLimit + 1
-      log.info('Trying to start %s again (%d/%d).', this.name, attempt, retryLimit)
+      log.info(`Trying to start ${this.name} again (${retryLimit - this._retryLimit + 1}/${retryLimit}).`)
       this.restart()
       this._retryLimit--
     } else if (this._retryLimit === 0) {
-      log.error('%s failed %d times (%s). Giving up.', this.name, retryLimit, this.error)
+      log.error(`${this.name} failed ${retryLimit} times (${this.error}). Giving up.`)
     } else {
-      log.debug('%s failed (%s). Not restarting.', this.name, this.error)
+      log.debug(`${this.name} failed (${this.error}). Not restarting.`)
     }
   })
 }

lib/middleware/karma.js

@@ -154,19 +154,19 @@ function createKarmaMiddleware (
         let requestedFileUrl
         log.debug('custom files', customContextFile, customDebugFile, customClientContextFile)
         if (isRequestingContextFile && customContextFile) {
-          log.debug('Serving customContextFile %s', customContextFile)
+          log.debug(`Serving customContextFile ${customContextFile}`)
           fileServer = serveFile
           requestedFileUrl = customContextFile
         } else if (isRequestingDebugFile && customDebugFile) {
-          log.debug('Serving customDebugFile %s', customDebugFile)
+          log.debug(`Serving customDebugFile ${customDebugFile}`)
           fileServer = serveFile
           requestedFileUrl = customDebugFile
         } else if (isRequestingClientContextFile && customClientContextFile) {
-          log.debug('Serving customClientContextFile %s', customClientContextFile)
+          log.debug(`Serving customClientContextFile ${customClientContextFile}`)
           fileServer = serveFile
           requestedFileUrl = customClientContextFile
         } else {
-          log.debug('Serving static request %s', requestUrl)
+          log.debug(`Serving static request ${requestUrl}`)
           fileServer = serveStaticFile
           requestedFileUrl = requestUrl
         }