Limit where certain arguments are allowed in Babel config.

packages/babel-core/src/transformation/file/options/build-config-chain.js

@@ -28,6 +28,7 @@ export default function buildConfigChain(opts: Object = {}) {
 
   try {
     builder.mergeConfig({
+      type: "arguments",
       options: opts,
       alias: "base",
       dirname: process.cwd(),
@@ -185,6 +186,7 @@ class ConfigChainBuilder {
 
     if (lines.length) {
       this.mergeConfig({
+        type: "options",
         options: { ignore: lines },
         alias: loc,
         dirname: path.dirname(loc),
@@ -231,6 +233,7 @@ class ConfigChainBuilder {
     }
 
     this.mergeConfig({
+      type: "options",
       options,
       alias: loc,
       dirname: path.dirname(loc),
@@ -240,6 +243,7 @@ class ConfigChainBuilder {
   }
 
   mergeConfig({
+    type,
     options,
     alias,
     loc,
@@ -266,6 +270,7 @@ class ConfigChainBuilder {
       delete options.env;
 
       this.mergeConfig({
+        type,
         options: envOpts,
         alias: `${alias}.env.${envKey}`,
         dirname: dirname,
@@ -273,6 +278,7 @@ class ConfigChainBuilder {
     }
 
     this.configs.push({
+      type,
       options,
       alias,
       loc,

packages/babel-core/src/transformation/file/options/option-manager.js

@@ -25,6 +25,7 @@ type PluginObject = {
 };
 
 type MergeOptions = {
+  type: "arguments"|"options"|"preset",
   options?: Object,
   extending?: Object,
   alias: string,
@@ -188,6 +189,7 @@ export default class OptionManager {
    */
 
   mergeOptions({
+    type,
     options: rawOpts,
     extending: extendingOpts,
     alias,
@@ -213,6 +215,23 @@ export default class OptionManager {
     dirname = dirname || process.cwd();
     loc = loc || alias;
 
+    if (type !== "arguments") {
+      if (opts.filename !== undefined) {
+        throw new Error(`${alias}.filename is only allowed as a root argument`);
+      }
+
+      if (opts.babelrc !== undefined) {
+        throw new Error(`${alias}.babelrc is only allowed as a root argument`);
+      }
+    }
+
+    if (type === "preset") {
+      if (opts.only !== undefined) throw new Error(`${alias}.only is not supported in a preset`);
+      if (opts.ignore !== undefined) throw new Error(`${alias}.ignore is not supported in a preset`);
+      if (opts.extends !== undefined) throw new Error(`${alias}.extends is not supported in a preset`);
+      if (opts.env !== undefined) throw new Error(`${alias}.env is not supported in a preset`);
+    }
+
     if (opts.sourceMap !== undefined) {
       if (opts.sourceMaps !== undefined) {
         throw new Error(`Both ${alias}.sourceMap and .sourceMaps have been set`);
@@ -249,6 +268,7 @@ export default class OptionManager {
 
       opts.presets = this.resolvePresets(opts.presets, dirname, (preset, presetLoc) => {
         this.mergeOptions({
+          type: "preset",
           options: preset,
 
           // For `passPerPreset` we merge child options back into the preset object instead of the root.