✅ Fix typings in tests

Author: momocow

test/integration/util.ts

@@ -5,7 +5,7 @@ import path from 'node:path';
 import { promisify } from 'node:util';
 
 import express, { static as expressStatic } from 'express';
-import { Configuration, webpack } from 'webpack';
+import { Compiler, Configuration, webpack } from 'webpack';
 
 import { createFsFromVolume, Volume } from './volume';
 
@@ -15,6 +15,8 @@ export interface CompilerFileSystems {
   intermediateFileSystem?: Volume;
 }
 
+type IntermediateFileSystem = Compiler['intermediateFileSystem'];
+
 export async function compile(
   input: Volume,
   config: Configuration,
@@ -25,8 +27,8 @@ export async function compile(
 
   compiler.inputFileSystem = createFsFromVolume(input);
   compiler.outputFileSystem = createFsFromVolume(output);
-  compiler.intermediateFileSystem =
-    intermediateFileSystem ?? (compiler.outputFileSystem as Volume);
+  compiler.intermediateFileSystem = (intermediateFileSystem ??
+    compiler.outputFileSystem) as IntermediateFileSystem;
 
   const stats = await promisify(compiler.run.bind(compiler))();
   await promisify(compiler.close.bind(compiler))();

test/integration/volume.ts

@@ -1,2 +1,9 @@
-export { createFsFromVolume } from 'memfs';
-export { Volume } from 'memfs/lib/volume';
+import { createFsFromVolume as memfsCreateFsFromVolume } from 'memfs';
+import { Volume } from 'memfs/lib/volume';
+import { InputFileSystem, OutputFileSystem } from 'webpack';
+
+export const createFsFromVolume = memfsCreateFsFromVolume as unknown as (
+  ...args: Parameters<typeof memfsCreateFsFromVolume>
+) => Volume & InputFileSystem & OutputFileSystem;
+
+export { Volume };