refactor: caching identifier generation

packages/@vue/cli-plugin-eslint/index.js

@@ -1,7 +1,27 @@
-module.exports = (api, { lintOnSave }) => {
-  if (lintOnSave) {
+module.exports = (api, options) => {
+  if (options.lintOnSave) {
     const extensions = require('./eslintOptions').extensions(api)
-    const cacheIdentifier = genCacheIdentifier(api.resolve('.'))
+
+    // eslint-loader doesn't bust cache when eslint config changes
+    // so we have to manually generate a cache identifier that takes the config
+    // into account.
+    const { genCacheConfig } = require('@vue/cli-shared-utils')
+    const { cacheIdentifier } = genCacheConfig(
+      api,
+      options,
+      [
+        'eslint-loader',
+        'eslint'
+      ],
+      [
+        '.eslintrc.js',
+        '.eslintrc.yaml',
+        '.eslintrc.yml',
+        '.eslintrc.json',
+        '.eslintrc',
+        'package.json'
+      ]
+    )
 
     api.chainWebpack(webpackConfig => {
       webpackConfig.module
@@ -18,7 +38,7 @@ module.exports = (api, { lintOnSave }) => {
               extensions,
               cache: true,
               cacheIdentifier,
-              emitWarning: lintOnSave !== 'error',
+              emitWarning: options.lintOnSave !== 'error',
               formatter: require('eslint/lib/formatters/codeframe')
             })
     })
@@ -38,33 +58,3 @@ module.exports = (api, { lintOnSave }) => {
     require('./lint')(args, api)
   })
 }
-
-// eslint-loader doesn't bust cache when eslint config changes
-// so we have to manually generate a cache identifier that takes the config
-// into account.
-function genCacheIdentifier (context) {
-  const fs = require('fs')
-  const path = require('path')
-  const files = [
-    '.eslintrc.js',
-    '.eslintrc.yaml',
-    '.eslintrc.yml',
-    '.eslintrc.json',
-    '.eslintrc',
-    'package.json'
-  ]
-
-  const configTimeStamp = (() => {
-    for (const file of files) {
-      if (fs.existsSync(path.join(context, file))) {
-        return fs.statSync(file).mtimeMs
-      }
-    }
-  })()
-
-  return JSON.stringify({
-    'eslint-loader': require('eslint-loader/package.json').version,
-    'eslint': require('eslint/package.json').version,
-    'config': configTimeStamp
-  })
-}

packages/@vue/cli-shared-utils/lib/cache.js

@@ -1,25 +1,44 @@
 const fs = require('fs')
-const path = require('path')
+const hash = require('hash-sum')
 
-exports.genCacheConfig = (api, options, id, configFile) => {
-  const cacheDirectory = process.env.VUE_CLI_TEST
-    ? path.resolve(__dirname, `../../../../node_modules/.cache/${id}`)
-    : api.resolve(`node_modules/.cache/${id}`)
+exports.genCacheConfig = (api, options, deps, configFiles) => {
+  if (!Array.isArray(deps)) {
+    deps = [deps]
+  }
+  const id = deps[0]
+  const cacheDirectory = api.resolve(`node_modules/.cache/${id}`)
 
   const variables = {
-    [id]: require(`${id}/package.json`).version,
     'cache-loader': require('cache-loader/package.json').version,
     env: process.env.NODE_ENV,
     test: !!process.env.VUE_CLI_TEST,
-    config: (options.chainWebpack || '').toString() + (options.configureWebpack || '').toString()
+    config: [options.chainWebpack, options.configureWebpack]
+  }
+
+  for (const dep of deps) {
+    variables[dep] = require(`${dep}/package.json`).version
+  }
+
+  const readConfig = file => {
+    const absolutePath = api.resolve(file)
+    if (fs.existsSync(absolutePath)) {
+      return fs.readFileSync(absolutePath, 'utf-8')
+    }
   }
-  if (configFile) {
-    const file = api.resolve(configFile)
-    if (fs.existsSync(file)) {
-      variables.configFile = fs.readFileSync(configFile, 'utf-8')
+
+  if (configFiles) {
+    if (!Array.isArray(configFiles)) {
+      configFiles = [configFiles]
+    }
+    for (const file of configFiles) {
+      const content = readConfig(file)
+      if (content) {
+        variables.configFiles = content
+        break
+      }
     }
   }
-  const cacheIdentifier = JSON.stringify(variables)
 
+  const cacheIdentifier = hash(variables)
   return { cacheDirectory, cacheIdentifier }
 }

packages/@vue/cli-shared-utils/package.json

@@ -22,6 +22,7 @@
     "chalk": "^2.3.0",
     "cmd-shim": "^2.0.2",
     "execa": "^0.9.0",
+    "hash-sum": "^1.0.2",
     "joi": "^12.0.0",
     "opn": "^5.2.0",
     "ora": "^1.3.0",