Enforce use of template literals

.eslintrc.yml

@@ -35,6 +35,7 @@ rules:
   strict: "error"
   arrow-body-style: ["error", "as-needed"]
   no-extension-in-require/main: "error"
+  prefer-template: "error"
 
   # Mocha-related.
   mocha/no-exclusive-tests: "error"

frontend/components/badge-examples.js

@@ -83,7 +83,7 @@ const Category = ({ category, examples, baseUrl, longCache, onClick }) => {
   }
   return (
     <div>
-      <Link to={'/examples/' + category.id}>
+      <Link to={`/examples/${category.id}`}>
         <h3 id={category.id}>{category.name}</h3>
       </Link>
       <table className="badge">

frontend/components/search-results.js

@@ -33,7 +33,7 @@ export default class SearchResults extends React.Component {
 
   renderCategoryHeadings() {
     return this.preparedExamples.map((category, i) => (
-      <Link to={'/examples/' + category.category.id} key={category.category.id}>
+      <Link to={`/examples/${category.category.id}`} key={category.category.id}>
         <h3 id={category.category.id}>{category.category.name}</h3>
       </Link>
     ))

lib/badge-cli.js

@@ -14,9 +14,7 @@ if (process.argv.length < 4) {
     'Or:    badge subject status right-color [left-color] [.output] [@style]'
   )
   console.log()
-  console.log(
-    '  colorscheme: one of ' + Object.keys(colorscheme).join(', ') + '.'
-  )
+  console.log(`  colorscheme: one of ${Object.keys(colorscheme).join(', ')}.`)
   console.log('  left-color, right-color:')
   console.log('    #xxx (three hex digits)')
   console.log('    #xxxxxx (six hex digits)')

lib/badge-data.js

@@ -21,7 +21,7 @@ function prependPrefix(s, prefix) {
     return undefined
   }
 
-  s = '' + s
+  s = `${s}`
 
   if (s.startsWith(prefix)) {
     return s
@@ -36,7 +36,7 @@ function isHexColor(s = '') {
 
 function makeColor(color) {
   if (isHexColor(color)) {
-    return '#' + color
+    return `#${color}`
   } else if (colorschemes[color] !== undefined) {
     return colorschemes[color].colorB
   } else if (isCSSColor(color)) {
@@ -52,7 +52,7 @@ function makeColorB(defaultColor, overrides) {
 
 function setBadgeColor(badgeData, color) {
   if (isHexColor(color)) {
-    badgeData.colorB = '#' + color
+    badgeData.colorB = `#${color}`
     delete badgeData.colorscheme
   } else if (colorschemes[color] !== undefined) {
     badgeData.colorscheme = color
@@ -68,12 +68,11 @@ function setBadgeColor(badgeData, color) {
 }
 
 function makeLabel(defaultLabel, overrides) {
-  return (
-    '' +
-    (overrides.label === undefined
+  return `${
+    overrides.label === undefined
       ? (defaultLabel || '').toLowerCase()
-      : overrides.label)
-  )
+      : overrides.label
+  }`
 }
 
 function getShieldsIcon(icon = '', color = '') {

lib/color-formatters.js

@@ -10,7 +10,7 @@ function version(version) {
   if (typeof version !== 'string' && typeof version !== 'number') {
     throw new Error(`Can't generate a version color for ${version}`)
   }
-  version = '' + version
+  version = `${version}`
   let first = version[0]
   if (first === 'v') {
     first = version[1]

lib/github-auth.js

@@ -34,12 +34,12 @@ function setRoutes(server) {
     }
     const query = queryString.stringify({
       client_id: serverSecrets.gh_client_id,
-      redirect_uri: baseUrl + '/github-auth/done',
+      redirect_uri: `${baseUrl}/github-auth/done`,
     })
     ask.res.statusCode = 302 // Found.
     ask.res.setHeader(
       'Location',
-      'https://github.com/login/oauth/authorize?' + query
+      `https://github.com/login/oauth/authorize?${query}`
     )
     end('')
   })
@@ -125,7 +125,7 @@ function sendTokenToAllServers(token) {
       ip =>
         new Promise((resolve, reject) => {
           const options = {
-            url: 'https://' + ip + '/github-auth/add-token',
+            url: `https://${ip}/github-auth/add-token`,
             method: 'POST',
             form: {
               shieldsSecret: serverSecrets.shieldsSecret,
@@ -298,7 +298,7 @@ function githubRequest(request, url, query, cb) {
 
   if (githubToken != null) {
     // Typically, GitHub user tokens grants us 12500 req/hour.
-    headers['Authorization'] = 'token ' + githubToken
+    headers['Authorization'] = `token ${githubToken}`
   } else if (serverSecrets && serverSecrets.gh_client_id) {
     // Using our OAuth App secret grants us 5000 req/hour
     // instead of the standard 60 req/hour.
@@ -308,7 +308,7 @@ function githubRequest(request, url, query, cb) {
 
   const qs = queryString.stringify(query)
   if (qs) {
-    url += '?' + qs
+    url += `?${qs}`
   }
 
   request(url, { headers: headers }, (err, res, buffer) => {

lib/load-logos.js

@@ -14,7 +14,7 @@ function loadLogos() {
       return
     }
     // filename is eg, github.svg
-    const svg = fs.readFileSync(logoDir + '/' + filename).toString()
+    const svg = fs.readFileSync(`${logoDir}/${filename}`).toString()
     const base64 = svg2base64(svg)
 
     // eg, github

lib/log.js

@@ -8,7 +8,7 @@ const listeners = []
 // eg. 4 becomes 04 but 17 stays 17.
 function pad(string) {
   string = String(string)
-  return string.length < 2 ? '0' + string : string
+  return string.length < 2 ? `0${string}` : string
 }
 
 // Compact date representation.

lib/logo-helper.js

@@ -11,7 +11,7 @@ function svg2base64(svg) {
   // Check if logo is already base64
   return isDataUri(svg)
     ? svg
-    : 'data:image/svg+xml;base64,' + Buffer.from(svg).toString('base64')
+    : `data:image/svg+xml;base64,${Buffer.from(svg).toString('base64')}`
 }
 
 module.exports = {

lib/lru-cache.js

@@ -107,7 +107,7 @@ Cache.prototype = {
         return 0
       }
     } else {
-      console.error("Unknown heuristic '" + this.type + "' for LRU cache.")
+      console.error(`Unknown heuristic '${this.type}' for LRU cache.`)
       return 1
     }
   },

lib/make-badge.js

@@ -22,16 +22,16 @@ templateFiles.forEach(async filename => {
     .readFileSync(path.join(__dirname, '..', 'templates', filename))
     .toString()
   const extension = path.extname(filename).slice(1)
-  const style = filename.slice(0, -('-template.' + extension).length)
+  const style = filename.slice(0, -`-template.${extension}`.length)
   // Compile the template. Necessary to always have a working template.
-  templates[style + '-' + extension] = dot.template(templateData)
+  templates[`${style}-${extension}`] = dot.template(templateData)
   if (extension === 'svg') {
     // Substitute dot code.
     const mapping = new Map()
     let mappingIndex = 1
     const untemplatedSvg = templateData.replace(/{{.*?}}/g, match => {
       // Weird substitution that currently works for all templates.
-      const mapKey = '99999990' + mappingIndex + '.1'
+      const mapKey = `99999990${mappingIndex}.1`
       mappingIndex++
       mapping.set(mapKey, match)
       return mapKey
@@ -74,7 +74,7 @@ templateFiles.forEach(async filename => {
       return
     }
 
-    templates[style + '-' + extension] = dot.template(svg)
+    templates[`${style}-${extension}`] = dot.template(svg)
   }
 })
 
@@ -125,7 +125,7 @@ function makeBadge(
   }
 ) {
   // String coercion.
-  text = text.map(value => '' + value)
+  text = text.map(value => `${value}`)
 
   if (format !== 'json') {
     format = 'svg'

lib/php-version.js

@@ -184,7 +184,7 @@ function minorVersion(version) {
     return ''
   }
 
-  return result[1] + '.' + (result[2] ? result[2] : '0')
+  return `${result[1]}.${result[2] ? result[2] : '0'}`
 }
 
 function versionReduction(versions, phpReleases) {
@@ -208,10 +208,10 @@ function versionReduction(versions, phpReleases) {
   // no missed versions
   if (first + versions.length - 1 === last) {
     if (last === phpReleases.length - 1) {
-      return '>= ' + (versions[0][2] === '0' ? versions[0][0] : versions[0]) // 7.0 -> 7
+      return `>= ${versions[0][2] === '0' ? versions[0][0] : versions[0]}` // 7.0 -> 7
     }
 
-    return versions[0] + ' - ' + versions[versions.length - 1]
+    return `${versions[0]} - ${versions[versions.length - 1]}`
   }
 
   return versions.join(', ')

lib/request-handler.js

@@ -107,7 +107,7 @@ function handleRequest(makeBadge, handlerOptions) {
       ask.res.setHeader('Cache-Control', 'no-cache, no-store, must-revalidate')
       ask.res.setHeader('Expires', reqTime.toGMTString())
     } else {
-      ask.res.setHeader('Cache-Control', 'max-age=' + maxAge)
+      ask.res.setHeader('Cache-Control', `max-age=${maxAge}`)
       ask.res.setHeader(
         'Expires',
         new Date(+reqTime + maxAge * 1000).toGMTString()

lib/result-sender.js

@@ -29,7 +29,7 @@ function sendSVG(res, askres, end) {
 }
 
 function sendOther(format, res, askres, end) {
-  askres.setHeader('Content-Type', 'image/' + format)
+  askres.setHeader('Content-Type', `image/${format}`)
   svg2img(res, format)
     .then(data => {
       end(null, { template: streamFromString(data) })

lib/service-test-runner/runner.js

@@ -51,7 +51,7 @@ class Runner {
 
     // Throw at the end, to provide a better error message.
     if (missingServices.length > 0) {
-      throw Error('Unknown services: ' + missingServices.join(', '))
+      throw Error(`Unknown services: ${missingServices.join(', ')}`)
     }
   }
 

lib/suggest.js

@@ -32,7 +32,7 @@ function suggest(allowedOrigin, githubApiProvider, data, end, ask) {
   try {
     url = nodeUrl.parse(data.url)
   } catch (e) {
-    end({ err: '' + e })
+    end({ err: `${e}` })
     return
   }
   findSuggestions(githubApiProvider, url, end)
@@ -76,43 +76,37 @@ function twitterPage(url) {
   const path = url.path
   return Promise.resolve({
     name: 'Twitter',
-    link:
-      'https://twitter.com/intent/tweet?text=Wow:&url=' +
-      encodeURIComponent(url.href),
-    badge:
-      'https://img.shields.io/twitter/url/' +
-      schema +
-      '/' +
-      host +
-      path +
-      '.svg?style=social',
+    link: `https://twitter.com/intent/tweet?text=Wow:&url=${encodeURIComponent(
+      url.href
+    )}`,
+    badge: `https://img.shields.io/twitter/url/${schema}/${host}${path}.svg?style=social`,
   })
 }
 
 function githubIssues(user, repo) {
-  const userRepo = user + '/' + repo
+  const userRepo = `${user}/${repo}`
   return Promise.resolve({
     name: 'GitHub issues',
-    link: 'https://github.com/' + userRepo + '/issues',
-    badge: 'https://img.shields.io/github/issues/' + userRepo + '.svg',
+    link: `https://github.com/${userRepo}/issues`,
+    badge: `https://img.shields.io/github/issues/${userRepo}.svg`,
   })
 }
 
 function githubForks(user, repo) {
-  const userRepo = user + '/' + repo
+  const userRepo = `${user}/${repo}`
   return Promise.resolve({
     name: 'GitHub forks',
-    link: 'https://github.com/' + userRepo + '/network',
-    badge: 'https://img.shields.io/github/forks/' + userRepo + '.svg',
+    link: `https://github.com/${userRepo}/network`,
+    badge: `https://img.shields.io/github/forks/${userRepo}.svg`,
   })
 }
 
 function githubStars(user, repo) {
-  const userRepo = user + '/' + repo
+  const userRepo = `${user}/${repo}`
   return Promise.resolve({
     name: 'GitHub stars',
-    link: 'https://github.com/' + userRepo + '/stargazers',
-    badge: 'https://img.shields.io/github/stars/' + userRepo + '.svg',
+    link: `https://github.com/${userRepo}/stargazers`,
+    badge: `https://img.shields.io/github/stars/${userRepo}.svg`,
   })
 }
 

lib/text-formatters.js

@@ -57,13 +57,13 @@ function metric(n) {
     if (n >= limit) {
       n = Math.round(n / limit)
       if (n < 1000) {
-        return '' + n + metricPrefix[i]
+        return `${n}${metricPrefix[i]}`
       } else {
-        return '1' + metricPrefix[i + 1]
+        return `1${metricPrefix[i + 1]}`
       }
     }
   }
-  return '' + n
+  return `${n}`
 }
 
 // Remove the starting v in a string.
@@ -79,7 +79,7 @@ function omitv(version) {
 // - it is a date (yyyy-mm-dd)
 const ignoredVersionPatterns = /^[^0-9]|[0-9]{4}-[0-9]{2}-[0-9]{2}/
 function addv(version) {
-  version = '' + version
+  version = `${version}`
   if (version.startsWith('v') || ignoredVersionPatterns.test(version)) {
     return version
   } else {

lib/version.js

@@ -30,8 +30,8 @@ function latest(versions, { pre = false } = {}) {
     // coerce to string then lowercase otherwise alpha > RC
     version = versions.sort((a, b) =>
       semver.rcompare(
-        ('' + a).toLowerCase(),
-        ('' + b).toLowerCase(),
+        `${a}`.toLowerCase(),
+        `${b}`.toLowerCase(),
         /* loose */ true
       )
     )[0]

server.js

@@ -248,7 +248,7 @@ camp.route(
 
     // Cache management - the badge is constant.
     const cacheDuration = (3600 * 24 * 1) | 0 // 1 day.
-    ask.res.setHeader('Cache-Control', 'max-age=' + cacheDuration)
+    ask.res.setHeader('Cache-Control', `max-age=${cacheDuration}`)
     if (+new Date(ask.req.headers['if-modified-since']) >= +serverStartTime) {
       ask.res.statusCode = 304
       ask.res.end() // not modified.
@@ -286,7 +286,7 @@ camp.route(
 let bitFlip = false
 camp.route(/^\/flip\.svg$/, (data, match, end, ask) => {
   const cacheSecs = 60
-  ask.res.setHeader('Cache-Control', 'max-age=' + cacheSecs)
+  ask.res.setHeader('Cache-Control', `max-age=${cacheSecs}`)
   const reqTime = new Date()
   const date = new Date(+reqTime + cacheSecs * 1000).toGMTString()
   ask.res.setHeader('Expires', date)
@@ -306,7 +306,7 @@ camp.route(/^\/([^/]+)\/(.+).png$/, (data, match, end, ask) => {
 
   // Cache management - the badge is constant.
   const cacheDuration = (3600 * 24 * 1) | 0 // 1 day.
-  ask.res.setHeader('Cache-Control', 'max-age=' + cacheDuration)
+  ask.res.setHeader('Cache-Control', `max-age=${cacheDuration}`)
   if (+new Date(ask.req.headers['if-modified-since']) >= +serverStartTime) {
     ask.res.statusCode = 304
     ask.res.end() // not modified.