fix(types): add a global interface for Worker (#20243)

Co-authored-by: sapphi-red <[email protected]>

Author: samchungy

packages/vite/tsconfig.check.json

@@ -3,7 +3,7 @@
     "target": "ES2020",
     "moduleResolution": "node16",
     "module": "Node16",
-    "lib": ["ES2020", "WebWorker"], // ES2020 is very conservative check for client types, could be bumped if needed
+    "lib": ["ES2020"], // ES2020 is very conservative check for client types, could be bumped if needed
     "types": [], // Avoid checking unrelated node_modules types
     "noEmit": true,
     "strict": true,

packages/vite/types/importGlob.d.ts

@@ -36,6 +36,16 @@ export interface ImportGlobOptions<
 
 export type GeneralImportGlobOptions = ImportGlobOptions<boolean, string>
 
+/**
+ * Declare Worker in case DOM is not added to the tsconfig lib causing
+ * Worker interface is not defined. For developers with DOM lib added,
+ * the Worker interface will be merged correctly.
+ */
+declare global {
+  // eslint-disable-next-line @typescript-eslint/no-empty-object-type
+  interface Worker {}
+}
+
 export interface KnownAsTypeMap {
   raw: string
   url: string