fixture: watch cannot build files changed or added successfully (#2457)

1. For function 'fullBuild', the first statement 'opts' can be divided into
two parameters called "selectedLocales" and "reserveLocale", the order
isn't right, according to the caller of this function itself (See its
calling at server.js by 'build.fullBuild' and other related functions).
So switch them together.

2. Fix #2443 (comment) for watch, because we didn't pass the parameter into
the buildLocale, there'll be Unhandled Exception.

Author: Maledong

build.js

@@ -310,7 +310,7 @@ function getSource (callback) {
 // This is where the build is orchestrated from, as indicated by the function
 // name. It brings together all build steps and dependencies and executes them.
 function fullBuild (opts) {
-  const { preserveLocale, selectedLocales } = opts
+  const { selectedLocales, preserveLocale } = opts
   // Build static files.
   copyStatic()
   // Build layouts
@@ -340,3 +340,4 @@ exports.getSource = getSource
 exports.fullBuild = fullBuild
 exports.buildLocale = buildLocale
 exports.copyStatic = copyStatic
+exports.generateLocalesData = generateLocalesData

server.js

@@ -15,8 +15,9 @@ const mount = st({
 })
 
 const build = require('./build')
-
+const fs = require('fs')
 const port = process.env.PORT || 8080
+const junk = require('junk')
 
 const selectedLocales = process.env.DEFAULT_LOCALE ? process.env.DEFAULT_LOCALE.toLowerCase().split(',') : process.env.DEFAULT_LOCALE
 const preserveLocale = process.argv.includes('--preserveLocale')
@@ -44,19 +45,40 @@ function getLocale (filePath) {
   return filePath.slice(pre.length + 1, filePath.indexOf(path.sep, pre.length + 1))
 }
 
+// This function has two meanings:
+// 1. Build for the specific language.
+// 2. Choose what languages for the menu.
+function dynamicallyBuildOnLanguages (source, locale) {
+  if (!selectedLocales || selectedLocales.length === 0) {
+    fs.readdir(path.join(__dirname, 'locale'), (e, locales) => {
+      const filteredLocales = locales.filter(file => junk.not(file))
+      const localesData = build.generateLocalesData(filteredLocales)
+      build.buildLocale(source, locale, { preserveLocale, localesData })
+    })
+  } else {
+    const localesData = build.generateLocalesData(selectedLocales)
+    build.buildLocale(source, locale, { preserveLocale, localesData })
+  }
+}
+
 build.getSource((err, source) => {
   if (err) { throw err }
 
   locales.on('change', (filePath) => {
     const locale = getLocale(filePath)
+
     if (!selectedLocales || selectedLocales.includes(locale)) {
-      build.buildLocale(source, locale)
+      console.log(`The language ${locale} is changed, file is ${filePath}.`)
+      dynamicallyBuildOnLanguages(source, locale)
     }
   })
+
   locales.on('add', (filePath) => {
     const locale = getLocale(filePath)
+
     if (!selectedLocales || selectedLocales.includes(locale)) {
-      build.buildLocale(source, locale)
+      console.log(`The language ${locale} is changed, file is ${filePath}.`)
+      dynamicallyBuildOnLanguages(source, locale)
       locales.add(filePath)
     }
   })