Applies to 11ty/eleventy-plugin-rss#52 resolvePlugin only needs to be…

… async for i18n plugin.

src/UserConfig.js

@@ -4,6 +4,11 @@ import debugUtil from "debug";
 import { RetrieveGlobals } from "node-retrieve-globals";
 import { DeepCopy, TemplatePath } from "@11ty/eleventy-utils";
 
+import HtmlBasePlugin from "./Plugins/HtmlBasePlugin.js";
+import RenderPlugin from "./Plugins/RenderPlugin.js";
+import InputPathToUrlPlugin from "./Plugins/InputPathToUrl.js";
+// import I18nPlugin from "./Plugins/I18nPlugin.js";
+
 import EventEmitter from "./Util/AsyncEventEmitter.js";
 import EleventyCompatibility from "./Util/Compatibility.js";
 import EleventyBaseError from "./Errors/EleventyBaseError.js";
@@ -405,7 +410,7 @@ class UserConfig {
 		}
 
 		if (this.isPluginExecution() || options?.immediate) {
-			// might return a promise
+			// this might return a promise
 			return this._executePlugin(plugin, options);
 		} else {
 			this.plugins.push({
@@ -418,19 +423,30 @@ class UserConfig {
 
 	async resolvePlugin(name) {
 		let filenameLookup = {
-			"@11ty/eleventy/html-base-plugin": "./Plugins/HtmlBasePlugin.js",
+			"@11ty/eleventy/html-base-plugin": HtmlBasePlugin,
+			"@11ty/eleventy/render-plugin": RenderPlugin,
+			"@11ty/eleventy/inputpath-to-url-plugin": InputPathToUrlPlugin,
+
+			// requires async (`await resolvePlugin("@11ty/eleventy/i18n-plugin")`)
+			// to avoid preloading i18n dependencies.
+			// see https://github.com/11ty/eleventy-plugin-rss/issues/52
 			"@11ty/eleventy/i18n-plugin": "./Plugins/I18nPlugin.js",
-			"@11ty/eleventy/render-plugin": "./Plugins/RenderPlugin.js",
-			"@11ty/eleventy/inputpath-to-url-plugin": "./Plugins/InputPathToUrl.js",
 		};
+
 		if (!filenameLookup[name]) {
 			throw new Error(
 				`Invalid name "${name}" passed to resolvePlugin. Valid options: ${Object.keys(filenameLookup).join(", ")}`,
 			);
 		}
+
 		// Future improvement: add support for any npm package name?
-		let plugin = await import(filenameLookup[name]);
-		return plugin.default;
+		if (typeof filenameLookup[name] === "string") {
+			// returns promise
+			return import(filenameLookup[name]).then((plugin) => plugin.default);
+		}
+
+		// return reference
+		return filenameLookup[name];
 	}
 
 	hasPlugin(plugin) {

test/EleventyVirtualTemplatesTest.js

@@ -129,7 +129,7 @@ test("Virtual templates conflict", async (t) => {
 	});
 
 	let e = await t.throwsAsync(async () => {
-    await elev.toJSON();
+		await elev.toJSON();
 	});
 
 	t.is(e.message, "Virtual template conflict: you can’t add multiple virtual templates that have the same inputPath: virtual.md");
@@ -141,20 +141,20 @@ test("RSS virtual templates plugin", async (t) => {
 		config: function (eleventyConfig) {
 			eleventyConfig.addTemplate("virtual.md", `# Hello`, { tag: "posts" })
 
-      eleventyConfig.addPlugin(feedPlugin, {
-        type: "atom", // or "rss", "json"
-        outputPath: "/feed.xml",
-        collection: {
-          name: "posts", // iterate over `collections.posts`
-          limit: 10,     // 0 means no limit
-        },
-      });
+			eleventyConfig.addPlugin(feedPlugin, {
+				type: "atom", // or "rss", "json"
+				outputPath: "/feed.xml",
+				collection: {
+					name: "posts", // iterate over `collections.posts`
+					limit: 10,     // 0 means no limit
+				},
+			});
 		},
 	});
 
 	let results = await elev.toJSON();
 
 	t.deepEqual(results.length, 2);
-  let [ feed ] = results.filter(entry => entry.outputPath.endsWith(".xml"));
+	let [ feed ] = results.filter(entry => entry.outputPath.endsWith(".xml"));
 	t.truthy(feed.content.startsWith(`<?xml version="1.0" encoding="utf-8"?>`));
 });