chore: extract node compat helper to own file

packages/wrangler/src/__tests__/node-compat.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { getNodeCompatMode } from "../deployment-bundle/node-compat";
+import { getNodeCompatMode } from "../node-compat";
 
 describe("getNodeCompatMode", () => {
 	it("should return v2 mode when experimental:nodejs_compat_v2 flag is present", () => {

packages/wrangler/src/deployment-bundle/create-worker-upload-form.ts

@@ -2,8 +2,8 @@ import assert from "node:assert";
 import { readFileSync } from "node:fs";
 import path from "node:path";
 import { File, FormData } from "undici";
+import { stripExperimentalPrefixes } from "../node-compat";
 import { handleUnsafeCapnp } from "./capnp";
-import { stripExperimentalPrefixes } from "./node-compat";
 import type {
 	CfDurableObjectMigrations,
 	CfModuleType,

packages/wrangler/src/deployment-bundle/node-compat.ts

@@ -1,6 +1,6 @@
 import { UserError } from "../errors";
 import { logger } from "../logger";
-import type { Config } from "../config";
+import { getNodeCompatMode } from "../node-compat";
 
 /**
  * Wrangler can provide Node.js compatibility in a number of different modes:
@@ -89,44 +89,3 @@ export function validateNodeCompat({
 
 	return mode;
 }
-
-export function getNodeCompatMode({
-	compatibility_flags,
-	node_compat,
-}: Pick<Config, "compatibility_flags" | "node_compat">) {
-	const nodejsCompat = compatibility_flags.includes("nodejs_compat");
-	const nodejsCompatV2 = compatibility_flags.includes(
-		"experimental:nodejs_compat_v2"
-	);
-
-	let mode: NodeJSCompatMode;
-	if (nodejsCompatV2) {
-		mode = "v2";
-	} else if (nodejsCompat) {
-		mode = "v1";
-	} else if (node_compat) {
-		mode = "legacy";
-	} else {
-		mode = null;
-	}
-
-	return {
-		legacy: mode === "legacy",
-		mode,
-		nodejsCompat,
-		nodejsCompatV2,
-	};
-}
-
-/**
- * The nodejs_compat_v2 flag currently requires an `experimental:` prefix within Wrangler,
- * but this needs to be stripped before sending to workerd, since that doesn't know about that.
- *
- * TODO: Remove this function when we graduate nodejs_v2 to non-experimental.
- * See https://jira.cfdata.org/browse/DEVDASH-218
- */
-export function stripExperimentalPrefixes(
-	compatFlags: string[] | undefined
-): string[] | undefined {
-	return compatFlags?.map((flag) => flag.replace(/^experimental:/, ""));
-}

packages/wrangler/src/dev/miniflare.ts

@@ -18,10 +18,10 @@ import {
 } from "../ai/fetcher";
 import { readConfig } from "../config";
 import { ModuleTypeToRuleType } from "../deployment-bundle/module-collection";
-import { stripExperimentalPrefixes } from "../deployment-bundle/node-compat";
 import { withSourceURLs } from "../deployment-bundle/source-url";
 import { UserError } from "../errors";
 import { logger } from "../logger";
+import { stripExperimentalPrefixes } from "../node-compat";
 import { getSourceMappedString } from "../sourcemap";
 import { updateCheck } from "../update-check";
 import type { ServiceFetch } from "../api";

packages/wrangler/src/dev/remote.tsx

@@ -7,11 +7,11 @@ import { useErrorHandler } from "react-error-boundary";
 import { helpIfErrorIsSizeOrScriptStartup } from "../deploy/deploy";
 import { printBundleSize } from "../deployment-bundle/bundle-reporter";
 import { getBundleType } from "../deployment-bundle/bundle-type";
-import { stripExperimentalPrefixes } from "../deployment-bundle/node-compat";
 import { withSourceURLs } from "../deployment-bundle/source-url";
 import { getInferredHost } from "../dev";
 import { UserError } from "../errors";
 import { logger } from "../logger";
+import { stripExperimentalPrefixes } from "../node-compat";
 import { syncLegacyAssets } from "../sites";
 import {
 	getAccountChoices,

packages/wrangler/src/node-compat.ts

@@ -0,0 +1,51 @@
+import type { Config } from "./config";
+
+/**
+ * Wrangler can provide Node.js compatibility in a number of different modes:
+ * - "legacy" - this mode adds compile-time polyfills that are not well maintained and cannot work with workerd runtime builtins.
+ * - "v1" - this mode tells the workerd runtime to enable some Node.js builtin libraries (accessible only via `node:...` imports) but no globals.
+ * - "v2" - this mode tells the workerd runtime to enable more Node.js builtin libraries (accessible both with and without the `node:` prefix)
+ *   and also some Node.js globals such as `Buffer`; it also turns on additional compile-time polyfills for those that are not provided by the runtime.
+ */
+export type NodeJSCompatMode = "legacy" | "v1" | "v2" | null;
+
+export function getNodeCompatMode({
+	compatibility_flags,
+	node_compat,
+}: Pick<Config, "compatibility_flags" | "node_compat">) {
+	const nodejsCompat = compatibility_flags.includes("nodejs_compat");
+	const nodejsCompatV2 = compatibility_flags.includes(
+		"experimental:nodejs_compat_v2"
+	);
+
+	let mode: NodeJSCompatMode;
+	if (nodejsCompatV2) {
+		mode = "v2";
+	} else if (nodejsCompat) {
+		mode = "v1";
+	} else if (node_compat) {
+		mode = "legacy";
+	} else {
+		mode = null;
+	}
+
+	return {
+		legacy: mode === "legacy",
+		mode,
+		nodejsCompat,
+		nodejsCompatV2,
+	};
+}
+
+/**
+ * The nodejs_compat_v2 flag currently requires an `experimental:` prefix within Wrangler,
+ * but this needs to be stripped before sending to workerd, since that doesn't know about that.
+ *
+ * TODO: Remove this function when we graduate nodejs_v2 to non-experimental.
+ * See https://jira.cfdata.org/browse/DEVDASH-218
+ */
+export function stripExperimentalPrefixes(
+	compatFlags: string[] | undefined
+): string[] | undefined {
+	return compatFlags?.map((flag) => flag.replace(/^experimental:/, ""));
+}

packages/wrangler/src/type-generation/index.ts

@@ -4,11 +4,11 @@ import * as esmLexer from "es-module-lexer";
 import { findUpSync } from "find-up";
 import { findWranglerToml, readConfig } from "../config";
 import { getEntry } from "../deployment-bundle/entry";
-import { getNodeCompatMode } from "../deployment-bundle/node-compat";
 import { getVarsForDev } from "../dev/dev-vars";
 import { UserError } from "../errors";
 import { CommandLineArgsError } from "../index";
 import { logger } from "../logger";
+import { getNodeCompatMode } from "../node-compat";
 import { parseJSONC } from "../parse";
 import { printWranglerBanner } from "../update-check";
 import { generateRuntimeTypes } from "./runtime";