[parser] Improve getPluginOptions type

packages/babel-parser/src/parser/base.ts

@@ -5,7 +5,11 @@ import type ScopeHandler from "../util/scope";
 import type ExpressionScopeHandler from "../util/expression-scope";
 import type ClassScopeHandler from "../util/class-scope";
 import type ProductionParameterHandler from "../util/production-parameter";
-import type { PluginConfig } from "../typings";
+import type {
+  ParserPluginWithOptions,
+  PluginConfig,
+  PluginOptions,
+} from "../typings";
 
 export default class BaseParser {
   // Properties set by constructor in index.js
@@ -54,7 +58,12 @@ export default class BaseParser {
     }
   }
 
-  getPluginOption(plugin: string, name: string) {
-    return this.plugins.get(plugin)?.[name];
+  getPluginOption<
+    PluginName extends ParserPluginWithOptions[0],
+    OptionName extends keyof PluginOptions<PluginName>,
+  >(plugin: PluginName, name: OptionName) {
+    return (this.plugins.get(plugin) as null | PluginOptions<PluginName>)?.[
+      name
+    ];
   }
 }

packages/babel-parser/src/plugin-utils.ts

@@ -1,5 +1,9 @@
 import type Parser from "./parser";
-import type { PluginConfig } from "./typings";
+import type {
+  ParserPluginWithOptions,
+  PluginConfig,
+  PluginOptions,
+} from "./typings";
 
 export type Plugin = PluginConfig;
 
@@ -47,11 +51,10 @@ export function hasPlugin(
   });
 }
 
-export function getPluginOption(
-  plugins: PluginList,
-  name: string,
-  option: string,
-) {
+export function getPluginOption<
+  PluginName extends ParserPluginWithOptions[0],
+  OptionName extends keyof PluginOptions<PluginName>,
+>(plugins: PluginList, name: PluginName, option: OptionName) {
   const plugin = plugins.find(plugin => {
     if (Array.isArray(plugin)) {
       return plugin[0] === name;
@@ -60,9 +63,8 @@ export function getPluginOption(
     }
   });
 
-  if (plugin && Array.isArray(plugin)) {
-    // @ts-expect-error Fixme: should check whether option is defined
-    return plugin[1][option];
+  if (plugin && Array.isArray(plugin) && plugin.length > 1) {
+    return (plugin[1] as PluginOptions<PluginName>)[option];
   }
 
   return null;

packages/babel-parser/src/typings.ts

@@ -7,13 +7,11 @@ export type Plugin =
   | "classProperties"
   | "classStaticBlock" // Enabled by default
   | "decimal"
-  | "decorators"
   | "decorators-legacy"
   | "decoratorAutoAccessors"
   | "destructuringPrivate"
   | "doExpressions"
   | "dynamicImport"
-  | "estree"
   | "exportDefaultFrom"
   | "exportNamespaceFrom" // deprecated
   | "flow"
@@ -24,8 +22,6 @@ export type Plugin =
   | "jsx"
   | "logicalAssignment"
   | "importAssertions"
-  // @deprecated
-  | "moduleAttributes"
   | "moduleBlocks"
   | "moduleStringNames"
   | "nullishCoalescingOperator"
@@ -34,25 +30,29 @@ export type Plugin =
   | "optionalCatchBinding"
   | "optionalChaining"
   | "partialApplication"
-  | "pipelineOperator"
   | "placeholders"
   | "privateIn" // Enabled by default
-  | "recordAndTuple"
   | "regexpUnicodeSets"
   | "throwExpressions"
   | "topLevelAwait"
-  | "typescript"
-  | "v8intrinsic";
-
-export type PluginConfig = Plugin | ParserPluginWithOptions;
+  | "v8intrinsic"
+  | ParserPluginWithOptions[0];
 
 export type ParserPluginWithOptions =
   | ["decorators", DecoratorsPluginOptions]
+  | ["estree", { classFeatures?: boolean }]
+  // @deprecated
+  | ["moduleAttributes", { version: "may-2020" }]
   | ["pipelineOperator", PipelineOperatorPluginOptions]
   | ["recordAndTuple", RecordAndTuplePluginOptions]
   | ["flow", FlowPluginOptions]
   | ["typescript", TypeScriptPluginOptions];
 
+export type PluginConfig = Plugin | ParserPluginWithOptions;
+
+export type PluginOptions<PluginName extends ParserPluginWithOptions[0]> =
+  Extract<ParserPluginWithOptions, [PluginName, any]>[1];
+
 export interface DecoratorsPluginOptions {
   decoratorsBeforeExport?: boolean;
 }