fix: improve error message when the entrypoint is incorrect

Author: dario-piotrowicz

.changeset/brave-geckos-juggle.md

@@ -0,0 +1,5 @@
+---
+"wrangler": patch
+---
+
+fix: improve error message when the entrypoint is incorrect

fixtures/start-worker-node-test/src/config-errors.test.js

@@ -1,6 +1,5 @@
 import assert from "node:assert";
 import test, { describe } from "node:test";
-import { setTimeout } from "node:timers/promises";
 import getPort from "get-port";
 import { unstable_startWorker } from "wrangler";
 
@@ -20,7 +19,7 @@ describe("startWorker - configuration errors", () => {
 				assert(cause instanceof Error);
 				assert.match(
 					cause.message,
-					/The entry-point file at "not a real entrypoint" was not found./
+					/The entry-point file at "not a real entrypoint" was not found\./
 				);
 				return true;
 			}
@@ -88,9 +87,9 @@ describe("startWorker - configuration errors", () => {
 			worker.setConfig({ entrypoint: "not a real entrypoint" }, true),
 			(err) => {
 				assert(err instanceof Error);
-				assert.strictEqual(
+				assert.match(
 					err.message,
-					'The entry-point file at "not a real entrypoint" was not found.'
+					/The entry-point file at "not a real entrypoint" was not found\./
 				);
 				return true;
 			}

packages/wrangler/src/__tests__/deploy.test.ts

@@ -3762,8 +3762,7 @@ addEventListener('fetch', event => {});`
 
 				await expect(runWrangler("deploy ./assets")).rejects
 					.toThrowErrorMatchingInlineSnapshot(`
-					[Error: The entry-point file at "assets" was not found.
-					The provided entry-point path, "assets", points to a directory, rather than a file.
+					[Error: The provided entry-point path, "assets", points to a directory, rather than a file.
 
 					 If you want to deploy a directory of static assets, you can do so by using the \`--assets\` flag. For example:
 
@@ -8091,9 +8090,7 @@ addEventListener('fetch', event => {});`
 
 			await expect(runWrangler("deploy")).rejects
 				.toThrowErrorMatchingInlineSnapshot(`
-				[Error: The expected output file at "." was not found after running custom build: node -e "4+4;".
-				The \`main\` property in your wrangler.toml file should point to the file generated by the custom build.
-				The provided entry-point path, ".", points to a directory, rather than a file.
+				[Error: The provided entry-point path, ".", points to a directory, rather than a file.
 
 				Did you mean to set the main field to one of:
 				\`\`\`
@@ -8109,11 +8106,8 @@ addEventListener('fetch', event => {});`
 				"
 			`);
 			expect(std.err).toMatchInlineSnapshot(`
-				"[31mX [41;31m[[41;97mERROR[41;31m][0m [1mThe expected output file at \\".\\" was not found after running custom build: node -e \\"4+4;\\".[0m
+				"[31mX [41;31m[[41;97mERROR[41;31m][0m [1mThe provided entry-point path, \\".\\", points to a directory, rather than a file.[0m
 
-				  The \`main\` property in your wrangler.toml file should point to the file generated by the custom
-				  build.
-				  The provided entry-point path, \\".\\", points to a directory, rather than a file.
 
 				  Did you mean to set the main field to one of:
 				  \`\`\`

packages/wrangler/src/__tests__/startup-profiling.test.ts

@@ -61,7 +61,12 @@ describe("wrangler check startup", () => {
 		await expect(
 			runWrangler("check startup --args 'abc'")
 		).rejects.toThrowErrorMatchingInlineSnapshot(
-			`[Error: The entry-point file at "abc" was not found.]`
+			`
+			[Error: The entry-point file at "abc" was not found.
+
+			This might mean that your entry-point file needs to be generated (which is the general case when a framework is being used).
+			If that's the case please run your project's build command and try again.]
+		`
 		);
 	});
 

packages/wrangler/src/deployment-bundle/run-custom-build.ts

@@ -4,6 +4,7 @@ import { Writable } from "node:stream";
 import { configFileName, UserError } from "@cloudflare/workers-utils";
 import chalk from "chalk";
 import { execaCommand } from "execa";
+import dedent from "ts-dedent";
 import { logger } from "../logger";
 import type { Config } from "@cloudflare/workers-utils";
 
@@ -69,15 +70,11 @@ export async function runCustomBuild(
 		assertEntryPointExists(
 			expectedEntryAbsolute,
 			expectedEntryRelative,
-			`The expected output file at "${expectedEntryRelative}" was not found after running custom build: ${build.command}.\n` +
-				`The \`main\` property in your ${configFileName(configPath)} file should point to the file generated by the custom build.`
+			build.command,
+			configPath
 		);
 	} else {
-		assertEntryPointExists(
-			expectedEntryAbsolute,
-			expectedEntryRelative,
-			`The entry-point file at "${expectedEntryRelative}" was not found.`
-		);
+		assertEntryPointExists(expectedEntryAbsolute, expectedEntryRelative);
 	}
 }
 
@@ -87,14 +84,16 @@ export async function runCustomBuild(
 function assertEntryPointExists(
 	expectedEntryAbsolute: string,
 	expectedEntryRelative: string,
-	errorMessage: string
+	customBuildCommand?: string,
+	configPath?: string
 ) {
 	if (!fileExists(expectedEntryAbsolute)) {
 		throw new UserError(
 			getMissingEntryPointMessage(
-				errorMessage,
 				expectedEntryAbsolute,
-				expectedEntryRelative
+				expectedEntryRelative,
+				customBuildCommand,
+				configPath
 			)
 		);
 	}
@@ -107,16 +106,17 @@ function assertEntryPointExists(
  * nearby to the expected file path.
  */
 function getMissingEntryPointMessage(
-	message: string,
 	absoluteEntryPointPath: string,
-	relativeEntryPointPath: string
+	relativeEntryPointPath: string,
+	customBuildCommand?: string,
+	configPath?: string
 ): string {
 	if (
 		existsSync(absoluteEntryPointPath) &&
 		statSync(absoluteEntryPointPath).isDirectory()
 	) {
 		// The expected entry-point is a directory, so offer further guidance.
-		message += `\nThe provided entry-point path, "${relativeEntryPointPath}", points to a directory, rather than a file.\n`;
+		let message = `The provided entry-point path, "${relativeEntryPointPath}", points to a directory, rather than a file.\n`;
 
 		// Perhaps we can even guess what the correct path should be...
 		const possiblePaths: string[] = [];
@@ -147,8 +147,23 @@ function getMissingEntryPointMessage(
 				`\n If you want to deploy a directory of static assets, you can do so by using the \`--assets\` flag. For example:\n\n` +
 				`wrangler deploy --assets=./${relativeEntryPointPath}\n`;
 		}
+
+		return message;
 	}
-	return message;
+
+	if (customBuildCommand) {
+		return dedent`
+			The expected output file at "${relativeEntryPointPath}" was not found after running custom build: ${customBuildCommand}.
+			The \`main\` property in your ${configFileName(configPath)} file should point to the file generated by the custom build.
+		`;
+	}
+
+	return dedent`
+		 		The entry-point file at "${relativeEntryPointPath}" was not found.
+
+		 		This might mean that your entry-point file needs to be generated (which is the general case when a framework is being used).
+		 		If that's the case please run your project's build command and try again.
+		 	`;
 }
 
 /**