first commit

app_vue/node_modules/@vue/cli-service/lib/util/validateWebpackConfig.js

@@ -0,0 +1,38 @@
+module.exports = function validateWebpackConfig (
+  webpackConfig,
+  api,
+  options,
+  target = 'app'
+) {
+  const singleConfig = Array.isArray(webpackConfig)
+    ? webpackConfig[0]
+    : webpackConfig
+
+  const actualTargetDir = singleConfig.output.path
+
+  if (actualTargetDir !== api.resolve(options.outputDir)) {
+    // user directly modifies output.path in configureWebpack or chainWebpack.
+    // this is not supported because there's no way for us to give copy
+    // plugin the correct value this way.
+    throw new Error(
+      `\n\nConfiguration Error: ` +
+      `Avoid modifying webpack output.path directly. ` +
+      `Use the "outputDir" option instead.\n`
+    )
+  }
+
+  if (actualTargetDir === api.service.context) {
+    throw new Error(
+      `\n\nConfiguration Error: ` +
+      `Do not set output directory to project root.\n`
+    )
+  }
+
+  if (target === 'app' && singleConfig.output.publicPath !== options.publicPath) {
+    throw new Error(
+      `\n\nConfiguration Error: ` +
+      `Avoid modifying webpack output.publicPath directly. ` +
+      `Use the "publicPath" option instead.\n`
+    )
+  }
+}