Add tests

packages/wrangler/src/__tests__/navigator-user-agent.test.ts

@@ -0,0 +1,193 @@
+import assert from "node:assert";
+import { mkdir, writeFile, readFile } from "node:fs/promises";
+import path from "node:path";
+import dedent from "ts-dedent";
+import { bundleWorker } from "../deployment-bundle/bundle";
+import { noopModuleCollector } from "../deployment-bundle/module-collection";
+import { isNavigatorDefined } from "../navigator-user-agent";
+import { mockConsoleMethods } from "./helpers/mock-console";
+import { runInTempDir } from "./helpers/run-in-tmp";
+
+/*
+ * This file contains inline comments with the word "javascript"
+ * This signals to a compatible editor extension that the template string
+ * contents should be syntax-highlighted as JavaScript. One such extension
+ * is zjcompt.es6-string-javascript, but there are others.
+ */
+
+async function seedFs(files: Record<string, string>): Promise<void> {
+	for (const [location, contents] of Object.entries(files)) {
+		await mkdir(path.dirname(location), { recursive: true });
+		await writeFile(location, contents);
+	}
+}
+
+describe("isNavigatorDefined", () => {
+	test("default", () => {
+		expect(isNavigatorDefined(undefined)).toBe(false);
+	});
+
+	test("modern date", () => {
+		expect(isNavigatorDefined("2024-01-01")).toBe(true);
+	});
+
+	test("old date", () => {
+		expect(isNavigatorDefined("2000-01-01")).toBe(false);
+	});
+
+	test("switch date", () => {
+		expect(isNavigatorDefined("2022-03-21")).toBe(true);
+	});
+
+	test("before date", () => {
+		expect(isNavigatorDefined("2022-03-20")).toBe(false);
+	});
+
+	test("old date, but with flag", () => {
+		expect(isNavigatorDefined("2000-01-01", ["global_navigator"])).toBe(true);
+	});
+
+	test("old date, with disable flag", () => {
+		expect(isNavigatorDefined("2000-01-01", ["no_global_navigator"])).toBe(
+			false
+		);
+	});
+
+	test("new date, but with disable flag", () => {
+		expect(isNavigatorDefined("2024-01-01", ["no_global_navigator"])).toBe(
+			false
+		);
+	});
+
+	test("new date, with enable flag", () => {
+		expect(isNavigatorDefined("2024-01-01", ["global_navigator"])).toBe(true);
+	});
+
+	test("errors with disable and enable flags specified", () => {
+		try {
+			isNavigatorDefined("2024-01-01", [
+				"no_global_navigator",
+				"global_navigator",
+			]);
+			assert(false, "Unreachable");
+		} catch (e) {
+			expect(e).toMatchInlineSnapshot(
+				`[AssertionError: Can't both enable and disable a flag]`
+			);
+		}
+	});
+});
+
+// Does bundleWorker respect the value of `defineNavigatorUserAgent`?
+describe("defineNavigatorUserAgent is respected", () => {
+	runInTempDir();
+	const std = mockConsoleMethods();
+
+	it("defineNavigatorUserAgent = false, navigator preserved", async () => {
+		await seedFs({
+			"src/index.js": dedent/* javascript */ `
+			function randomBytes(length) {
+				if (navigator.userAgent !== "Cloudflare-Workers") {
+					return new Uint8Array(require("node:crypto").randomBytes(length));
+				} else {
+					return crypto.getRandomValues(new Uint8Array(length));
+				}
+			}
+			export default {
+				async fetch(request, env) {
+					return new Response(randomBytes(10))
+				},
+			};
+		`,
+		});
+
+		await bundleWorker(
+			{
+				file: path.resolve("src/index.js"),
+				directory: process.cwd(),
+				format: "modules",
+				moduleRoot: path.dirname(path.resolve("src/index.js")),
+			},
+			path.resolve("dist"),
+			{
+				bundle: true,
+				additionalModules: [],
+				moduleCollector: noopModuleCollector,
+				serveAssetsFromWorker: false,
+				doBindings: [],
+				define: {},
+				checkFetch: false,
+				targetConsumer: "deploy",
+				local: true,
+				projectRoot: process.cwd(),
+				defineNavigatorUserAgent: false,
+			}
+		);
+
+		// Build time warning that the dynamic import of `require("node:crypto")` may not be safe
+		expect(std.warn).toMatchInlineSnapshot(`
+		"▲ [WARNING] The package \\"node:crypto\\" wasn't found on the file system but is built into node.
+
+		  Your Worker may throw errors at runtime unless you enable the \\"nodejs_compat\\" compatibility flag.
+		  Refer to https://developers.cloudflare.com/workers/runtime-apis/nodejs/ for more details. Imported
+		  from:
+		   - src/index.js
+
+		"
+	`);
+		const fileContents = await readFile("dist/index.js", "utf8");
+
+		// navigator.userAgent should have been preserved as-is
+		expect(fileContents).toContain("navigator.userAgent");
+	});
+
+	it("defineNavigatorUserAgent = true, navigator treeshaken", async () => {
+		await seedFs({
+			"src/index.js": dedent/* javascript */ `
+			function randomBytes(length) {
+				if (navigator.userAgent !== "Cloudflare-Workers") {
+					return new Uint8Array(require("node:crypto").randomBytes(length));
+				} else {
+					return crypto.getRandomValues(new Uint8Array(length));
+				}
+			}
+			export default {
+				async fetch(request, env) {
+					return new Response(randomBytes(10))
+				},
+			};
+		`,
+		});
+
+		await bundleWorker(
+			{
+				file: path.resolve("src/index.js"),
+				directory: process.cwd(),
+				format: "modules",
+				moduleRoot: path.dirname(path.resolve("src/index.js")),
+			},
+			path.resolve("dist"),
+			{
+				bundle: true,
+				additionalModules: [],
+				moduleCollector: noopModuleCollector,
+				serveAssetsFromWorker: false,
+				doBindings: [],
+				define: {},
+				checkFetch: false,
+				targetConsumer: "deploy",
+				local: true,
+				projectRoot: process.cwd(),
+				defineNavigatorUserAgent: true,
+			}
+		);
+
+		// Build time warning is suppressed, because esbuild treeshakes the relevant code path
+		expect(std.warn).toMatchInlineSnapshot(`""`);
+
+		const fileContents = await readFile("dist/index.js", "utf8");
+
+		// navigator.userAgent should have been defined, and so should not be present in the bundle
+		expect(fileContents).not.toContain("navigator.userAgent");
+	});
+});

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

@@ -1,7 +1,7 @@
+import { relative } from "path";
 import chalk from "chalk";
 import { logger } from "../../logger";
 import type { Plugin } from "esbuild";
-import { relative } from "path";
 
 // Infinite loop detection
 const seen = new Set();
@@ -17,6 +17,8 @@ export const nodejsCompatPlugin: (silenceWarnings: boolean) => Plugin = (
 ) => ({
 	name: "nodejs_compat imports plugin",
 	setup(pluginBuild) {
+		seen.clear();
+		warnedPackaged.clear();
 		pluginBuild.onResolve(
 			{ filter: /node:.*/ },
 			async ({ path, kind, resolveDir, ...opts }) => {

packages/wrangler/src/navigator-user-agent.ts

@@ -5,8 +5,10 @@ export function isNavigatorDefined(
 	compatibility_flags: string[] = []
 ) {
 	assert(
-		compatibility_flags.includes("global_navigator") &&
-			compatibility_flags.includes("no_global_navigator"),
+		!(
+			compatibility_flags.includes("global_navigator") &&
+			compatibility_flags.includes("no_global_navigator")
+		),
 		"Can't both enable and disable a flag"
 	);
 	if (compatibility_flags.includes("global_navigator")) {
@@ -15,5 +17,5 @@ export function isNavigatorDefined(
 	if (compatibility_flags.includes("no_global_navigator")) {
 		return false;
 	}
-	return !compatibility_date || compatibility_date >= "2022-03-21";
+	return !!compatibility_date && compatibility_date >= "2022-03-21";
 }

packages/wrangler/src/pages/build.ts

@@ -5,6 +5,7 @@ import { writeAdditionalModules } from "../deployment-bundle/find-additional-mod
 import { FatalError, UserError } from "../errors";
 import { logger } from "../logger";
 import * as metrics from "../metrics";
+import { isNavigatorDefined } from "../navigator-user-agent";
 import { buildFunctions } from "./buildFunctions";
 import {
 	EXIT_CODE_FUNCTIONS_NO_ROUTES_ERROR,
@@ -21,7 +22,6 @@ import type {
 	CommonYargsArgv,
 	StrictYargsOptionsToInterface,
 } from "../yargs-types";
-import { isNavigatorDefined } from "../navigator-user-agent";
 
 export type PagesBuildArgs = StrictYargsOptionsToInterface<typeof Options>;