fix(wrangler): use require.resolve to resolve unenv path (#7804)

Author: vicb

.changeset/little-pugs-change.md

@@ -0,0 +1,5 @@
+---
+"wrangler": patch
+---
+
+fix(wrangler): use require.resolve to resolve unenv path

packages/wrangler/src/deployment-bundle/esbuild-plugins/hybrid-nodejs-compat.ts

@@ -1,7 +1,7 @@
 import { builtinModules } from "node:module";
 import nodePath from "node:path";
 import dedent from "ts-dedent";
-import { cloudflare, defineEnv } from "unenv";
+import { cloudflare, env, nodeless } from "unenv";
 import { getBasePath } from "../../paths";
 import type { Plugin, PluginBuild } from "esbuild";
 
@@ -11,31 +11,17 @@ const REQUIRED_UNENV_ALIAS_NAMESPACE = "required-unenv-alias";
 /**
  * ESBuild plugin to apply the unenv preset.
  *
- * @param unenvResolvePaths Root paths used to resolve absolute paths.
+ * @param _unenvResolvePaths Root paths used to resolve absolute paths.
  * @returns ESBuild plugin
  */
-export function nodejsHybridPlugin(unenvResolvePaths?: string[]): Plugin {
-	// Get the resolved environment.
-	const { env } = defineEnv({
-		nodeCompat: true,
-		presets: [cloudflare],
-		resolve: {
-			paths: unenvResolvePaths,
-		},
-	});
-	const { alias, inject, external } = env;
-	// Get the unresolved alias.
-	const unresolvedAlias = defineEnv({
-		nodeCompat: true,
-		presets: [cloudflare],
-		resolve: false,
-	}).env.alias;
+export function nodejsHybridPlugin(_unenvResolvePaths?: string[]): Plugin {
+	const { alias, inject, external } = env(nodeless, cloudflare);
 	return {
 		name: "hybrid-nodejs_compat",
 		setup(build) {
 			errorOnServiceWorkerFormat(build);
 			handleRequireCallsToNodeJSBuiltins(build);
-			handleUnenvAliasedPackages(build, unresolvedAlias, alias, external);
+			handleUnenvAliasedPackages(build, alias, external);
 			handleNodeJSGlobals(build, inject);
 		},
 	};
@@ -111,26 +97,38 @@ function handleRequireCallsToNodeJSBuiltins(build: PluginBuild) {
  * Handles aliased NPM packages.
  *
  * @param build ESBuild PluginBuild.
- * @param unresolvedAlias Unresolved aliases from the presets.
  * @param alias Aliases resolved to absolute paths.
  * @param external external modules.
  */
 function handleUnenvAliasedPackages(
 	build: PluginBuild,
-	unresolvedAlias: Record<string, string>,
 	alias: Record<string, string>,
 	external: string[]
 ) {
-	const UNENV_ALIAS_RE = new RegExp(`^(${Object.keys(alias).join("|")})$`);
+	// esbuild expects alias paths to be absolute
+	const aliasAbsolute: Record<string, string> = {};
+	for (const [module, unresolvedAlias] of Object.entries(alias)) {
+		try {
+			aliasAbsolute[module] = require
+				.resolve(unresolvedAlias)
+				.replace(/\.cjs$/, ".mjs");
+		} catch (e) {
+			// this is an alias for package that is not installed in the current app => ignore
+		}
+	}
+
+	const UNENV_ALIAS_RE = new RegExp(
+		`^(${Object.keys(aliasAbsolute).join("|")})$`
+	);
 
 	build.onResolve({ filter: UNENV_ALIAS_RE }, (args) => {
-		const unresolved = unresolvedAlias[args.path];
+		const unresolvedAlias = alias[args.path];
 		// Convert `require()` calls for NPM packages to a virtual ES Module that can be imported avoiding the require calls.
 		// Note: Does not apply to Node.js packages that are handled in `handleRequireCallsToNodeJSBuiltins`
 		if (
 			args.kind === "require-call" &&
-			(unresolved.startsWith("unenv/runtime/npm/") ||
-				unresolved.startsWith("unenv/runtime/mock/"))
+			(unresolvedAlias.startsWith("unenv/runtime/npm/") ||
+				unresolvedAlias.startsWith("unenv/runtime/mock/"))
 		) {
 			return {
 				path: args.path,
@@ -140,8 +138,8 @@ function handleUnenvAliasedPackages(
 
 		// Resolve the alias to its absolute path and potentially mark it as external
 		return {
-			path: alias[args.path],
-			external: external.includes(unresolved),
+			path: aliasAbsolute[args.path],
+			external: external.includes(unresolvedAlias),
 		};
 	});