fix: ensure that alias config gets passed through to the bundler wh…

…en using new `--x-dev-env` (#6903)

Fixes #6898

.changeset/grumpy-apples-juggle.md

@@ -0,0 +1,7 @@
+---
+"wrangler": patch
+---
+
+fix: ensure that `alias` config gets passed through to the bundler when using new `--x-dev-env`
+
+Fixes #6898

packages/wrangler/src/__tests__/api/startDevWorker/ConfigController.test.ts

@@ -123,14 +123,20 @@ describe("ConfigController", () => {
 			dev: {
 				origin: { hostname: "myexample.com" },
 			},
+			build: {
+				alias: { foo: "bar" },
+			},
 		});
-		// expect `dev` field to be overwritten and all other config to remain intact
+		// expect `dev` and `build.alias` fields to be overwritten and all other config to remain intact
 		await expect(event3).resolves.toMatchObject({
 			type: "configUpdate",
 			config: {
 				entrypoint: path.join(process.cwd(), "src/index.ts"),
 				directory: process.cwd(),
 				build: {
+					alias: {
+						foo: "bar",
+					},
 					additionalModules: [],
 					define: {},
 					format: "modules",

packages/wrangler/src/api/startDevWorker/ConfigController.ts

@@ -257,6 +257,7 @@ async function resolveConfig(
 		triggers: await resolveTriggers(config, input),
 		env: input.env,
 		build: {
+			alias: input.build?.alias ?? config.alias,
 			additionalModules: input.build?.additionalModules ?? [],
 			processEntrypoint: Boolean(input.build?.processEntrypoint),
 			bundle: input.build?.bundle ?? !config.no_bundle,