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node_modules/webpack-dev-middleware/dist/utils/setupOutputFileSystem.js

@@ -0,0 +1,58 @@
+"use strict";
+
+const path = require("path");
+
+const memfs = require("memfs");
+/** @typedef {import("webpack").MultiCompiler} MultiCompiler */
+
+/** @typedef {import("../index.js").IncomingMessage} IncomingMessage */
+
+/** @typedef {import("../index.js").ServerResponse} ServerResponse */
+
+/**
+ * @template {IncomingMessage} Request
+ * @template {ServerResponse} Response
+ * @param {import("../index.js").Context<Request, Response>} context
+ */
+
+
+function setupOutputFileSystem(context) {
+  let outputFileSystem;
+
+  if (context.options.outputFileSystem) {
+    const {
+      outputFileSystem: outputFileSystemFromOptions
+    } = context.options; // Todo remove when we drop webpack@4 support
+
+    if (typeof outputFileSystemFromOptions.join !== "function") {
+      throw new Error("Invalid options: options.outputFileSystem.join() method is expected");
+    } // Todo remove when we drop webpack@4 support
+    // @ts-ignore
+
+
+    if (typeof outputFileSystemFromOptions.mkdirp !== "function") {
+      throw new Error("Invalid options: options.outputFileSystem.mkdirp() method is expected");
+    }
+
+    outputFileSystem = outputFileSystemFromOptions;
+  } else {
+    outputFileSystem = memfs.createFsFromVolume(new memfs.Volume()); // TODO: remove when we drop webpack@4 support
+    // @ts-ignore
+
+    outputFileSystem.join = path.join.bind(path);
+  }
+
+  const compilers =
+  /** @type {MultiCompiler} */
+  context.compiler.compilers || [context.compiler];
+
+  for (const compiler of compilers) {
+    compiler.outputFileSystem = outputFileSystem;
+  } // @ts-ignore
+  // eslint-disable-next-line no-param-reassign
+
+
+  context.outputFileSystem = outputFileSystem;
+}
+
+module.exports = setupOutputFileSystem;