⭐ new(rule): add no-missing-key rule

lib/index.js

@@ -1,6 +1,6 @@
 /**
  * @fileoverview ESLint plugin for vue-i18n
- * @author kazuya kawaguchi
+ * @author kazuya kawaguchi (a.k.a. kazupon)
  */
 'use strict'
 
@@ -14,7 +14,7 @@
 
 // import all rules in lib/rules
 module.exports.rules = {
-  // add your processors here
+  'no-missing-key': require('./rules/no-missing-key')
 }
 
 // import processors

lib/rules/no-missing-key.js

@@ -0,0 +1,87 @@
+/**
+ * @author kazuya kawaguchi (a.k.a. kazupon)
+ */
+'use strict'
+
+const {
+  defineTemplateBodyVisitor,
+  loadLocaleMessages,
+  findMissingsFromLocaleMessages
+} = require('../utils/index')
+
+let localeMessages = null // cache
+
+function create (context) {
+  const { settings } = context
+  const localeDir = settings['vue-i18n'].localeDir
+  localeMessages = localeMessages || loadLocaleMessages(localeDir)
+
+  return defineTemplateBodyVisitor(context, {
+    "VAttribute[directive=true][key.name='t']" (node) {
+      checkDirective(context, localeDir, localeMessages, node)
+    },
+
+    "VAttribute[directive=true][key.name.name='t']" (node) {
+      checkDirective(context, localeDir, localeMessages, node)
+    },
+
+    CallExpression (node) {
+      checkCallExpression(context, localeDir, localeMessages, node)
+    }
+  }, {
+    CallExpression (node) {
+      checkCallExpression(context, localeDir, localeMessages, node)
+    }
+  })
+}
+
+function checkDirective (context, localeDir, localeMessages, node) {
+  if ((node.value && node.value.type === 'VExpressionContainer') &&
+  (node.value.expression && node.value.expression.type === 'Literal')) {
+    const key = node.value.expression.value
+    if (!key) {
+      // TODO: should be error
+      return
+    }
+    const missings = findMissingsFromLocaleMessages(localeMessages, key, localeDir)
+    if (missings.length) {
+      missings.forEach(missing => context.report({ node, ...missing }))
+    }
+  }
+}
+
+function checkCallExpression (context, localeDir, localeMessages, node) {
+  const funcName = (node.callee.type === 'MemberExpression' && node.callee.property.name) || node.callee.name
+
+  if (!/^(\$t|t|\$tc|tc)$/.test(funcName) || !node.arguments || !node.arguments.length) {
+    return
+  }
+
+  const [keyNode] = node.arguments
+  if (keyNode.type !== 'Literal') { return }
+
+  const key = keyNode.value
+  if (!key) {
+    // TODO: should be error
+    return
+  }
+
+  const missings = findMissingsFromLocaleMessages(localeMessages, key, localeDir)
+  if (missings.length) {
+    missings.forEach(missing => context.report({ node, ...missing }))
+  }
+}
+
+module.exports = {
+  meta: {
+    type: 'problem',
+    docs: {
+      description: 'disallow missing locale message key at localization methods',
+      category: 'Possible Errors',
+      recommended: true
+    },
+    fixable: null,
+    schema: []
+  },
+  create
+}

lib/utils/index.js

@@ -0,0 +1,55 @@
+/**
+ * @author kazuya kawaguchi (a.k.a. kazupon)
+ */
+'use strict'
+
+const glob = require('glob')
+const { resolve } = require('path')
+
+function defineTemplateBodyVisitor (context, templateBodyVisitor, scriptVisitor) {
+  if (context.parserServices.defineTemplateBodyVisitor === null) {
+    context.report({
+      loc: { line: 1, column: 0 },
+      message: 'Use the latest vue-eslint-parser. See also https://github.com/vuejs/eslint-plugin-vue#what-is-the-use-the-latest-vue-eslint-parser-error'
+    })
+    return {}
+  }
+  return context.parserServices.defineTemplateBodyVisitor(templateBodyVisitor, scriptVisitor)
+}
+
+function loadLocaleMessages (pattern) {
+  const files = glob.sync(pattern)
+  return files.map(file => {
+    const path = resolve(process.cwd(), file)
+    const filename = file.replace(/^.*(\\|\/|:)/, '')
+    const messages = require(path)
+    return { path: file, filename, messages }
+  })
+}
+
+function findMissingsFromLocaleMessages (localeMessages, key) {
+  const missings = []
+  const paths = key.split('.')
+  localeMessages.forEach(localeMessage => {
+    const length = paths.length
+    let last = localeMessage.messages
+    let i = 0
+    while (i < length) {
+      const value = last[paths[i]]
+      if (value === undefined) {
+        missings.push({
+          message: `'${key}' does not exist in '${localeMessage.path}'`
+        })
+      }
+      last = value
+      i++
+    }
+  })
+  return missings
+}
+
+module.exports = {
+  defineTemplateBodyVisitor,
+  loadLocaleMessages,
+  findMissingsFromLocaleMessages
+}

tests/fixtures/locales/en.json

@@ -0,0 +1,14 @@
+{
+  "hello": "hello world",
+  "messages": {
+    "hello": "hi DIO!",
+    "link": "@:message.hello",
+    "nested": {
+      "hello": "hi jojo!"
+    }
+  },
+  "hello_dio": "hello underscore DIO!",
+  "hello {name}": "hello {name}!",
+  "hello-dio": "hello hyphen DIO!",
+  "foo.bar.buz": "hi flat key!"
+}

tests/fixtures/locales/ja.json

@@ -0,0 +1,14 @@
+{
+  "hello": "ハローワールド",
+  "messages": {
+    "hello": "こんにちは、DIO！",
+    "link": "@:message.hello",
+    "nested": {
+      "hello": "こんにちは、ジョジョ!"
+    }
+  },
+  "hello_dio": "こんにちは、アンダースコア DIO！",
+  "hello {name}": "こんにちは、{name}！",
+  "hello-dio": "こんにちは、ハイフン DIO！",
+  "foo.bar.buz": "こんにちは、フラットなキー！"
+}

tests/lib/rules/no-missing-key.js

@@ -0,0 +1,91 @@
+/**
+ * @author kazuya kawaguchi (a.k.a. kazupon)
+ */
+'use strict'
+
+const RuleTester = require('eslint').RuleTester
+const rule = require('../../../lib/rules/no-missing-key')
+
+const baseDir = './tests/fixtures/locales'
+const resolve = file => `${baseDir}/${file}`
+
+const settings = {
+  'vue-i18n': {
+    localeDir: `${baseDir}/*.json`
+  }
+}
+
+const tester = new RuleTester({
+  parser: 'vue-eslint-parser',
+  parserOptions: { ecmaVersion: 2015 }
+})
+
+tester.run('no-missing-key', rule, {
+  valid: [{
+    // basic key
+    settings,
+    code: `$t('hello')`
+  }, {
+    // nested key
+    settings,
+    code: `t('messages.nested.hello')`
+  }, {
+    // linked key
+    settings,
+    code: `$tc('messages.hello.link')`
+  }, {
+    // hypened key
+    settings,
+    code: `tc('hello-dio')`
+  }, {
+    // key like the message
+    settings,
+    code: `$t('hello {name}')`
+  }, {
+    // Identifier
+    settings,
+    code: `$t(key)`
+  }, {
+    // using mustaches in template block
+    settings,
+    code: `<template>
+      <p>{{ $t('hello') }}</p>
+    </template>`
+  }, {
+    // using custom directive in template block
+    settings,
+    code: `<template>
+      <p v-t="'hello'"></p>
+    </template>`
+  }],
+
+  invalid: [{
+    // basic
+    settings,
+    code: `$t('missing')`,
+    errors: [
+      `'missing' does not exist in '${resolve('en.json')}'`,
+      `'missing' does not exist in '${resolve('ja.json')}'`
+    ]
+  }, {
+    // using mustaches in template block
+    settings,
+    code: `<template>
+      <p>{{ $t('missing') }}</p>
+    </template>`,
+    errors: [
+      `'missing' does not exist in '${resolve('en.json')}'`,
+      `'missing' does not exist in '${resolve('ja.json')}'`
+    ]
+  }, {
+    // using custom directive in template block
+    settings,
+    code: `<template>
+      <p v-t="'missing'"></p>
+    </template>`,
+    errors: [
+      `'missing' does not exist in '${resolve('en.json')}'`,
+      `'missing' does not exist in '${resolve('ja.json')}'`
+    ]
+  }]
+})