Adds upgrade helper for 11ty/eleventy#3124

.eleventy.js

@@ -20,6 +20,7 @@ module.exports = function(eleventyConfig) {
   eleventyConfig.addPlugin(require("./src/html-output-suffix.js"));
   eleventyConfig.addPlugin(require("./src/alias-template-formats.js"));
   eleventyConfig.addPlugin(require("./src/empty-formats.js"));
+  eleventyConfig.addPlugin(require("./src/plugin-land.js"));
 
   eleventyConfig.on("eleventy.after", () => {
     console.log(chalk.blue(`[${pkg.name}] This plugin is intended for temporary use: once you’re satisfied please remove this plugin from your project!`));

package.json

@@ -30,6 +30,7 @@
   "bugs": "https://github.com/11ty/eleventy-upgrade-help/issues",
   "homepage": "https://www.11ty.dev/",
   "dependencies": {
+    "fast-glob": "^3.3.2",
     "kleur": "^4.1.5",
     "minimist": "^1.2.8",
     "semver": "^7.6.3"

src/alias-template-formats.js

@@ -9,6 +9,9 @@ module.exports = function(eleventyConfig) {
 			console.log(chalk.green(`[${pkg.name}] PASSED`), `No aliases were added via \`eleventyConfig.addExtension()\`. If you had added an alias, it would need to be also added to your active template formats. Learn more about template formats: https://www.11ty.dev/docs/config/#template-formats or about this change: https://github.com/11ty/eleventy/issues/3302`);
 		} else {
 			for(let { key, extension, aliasKey } of eleventyConfig.extensionMap) {
+				if(!aliasKey) {
+					continue;
+				}
 				if(!templateFormatsActive.includes(extension)) {
 					console.log(chalk.red(`[${pkg.name}] ERROR`), `Aliases added via \`eleventyConfig.addExtension()\` must be added to your active template formats, via \`--formats=${extension}\` on the command line, the \`templateFormats: "${extension}"\` configuration object property, \`eleventyConfig.setTemplateFormats("${extension}")\`, or \`eleventyConfig.addTemplateFormats("${extension}")\` (additive). This *might* be what you want if you added a plugin but don’t want to currently process ${extension} files in Eleventy. Learn more about template formats: https://www.11ty.dev/docs/config/#template-formats or about this change: https://github.com/11ty/eleventy/issues/3302`);
 				} else {

src/empty-formats.js

@@ -1,4 +1,3 @@
-const fs = require("node:fs");
 const chalk = require("kleur");
 const pkg = require("../package.json");
 
@@ -12,6 +11,6 @@ module.exports = function(eleventyConfig) {
 	if(argv.formats || argv.formats === undefined) {
 		console.log(chalk.green(`[${pkg.name}] PASSED`), `You aren’t using \`--formats=\` or  \`--formats=''\` but if you were you should know that these are now empty template format sets. In previous versions, they were aliased to "*". Read more: https://github.com/11ty/eleventy/issues/3255`);
 	} else if(argv.formats === "" || argv.formats === null) {
-		console.log(chalk.red(`[${pkg.name}] ERROR`), `In Eleventy 3.0 \`--formats=""\` and \`formats=\` are empty template format sets. Previous versions aliased these to "*". Use \`--formats=*\` if you want that behavior in 3.0. Read more: https://github.com/11ty/eleventy/issues/3255`);
+		console.log(chalk.red(`[${pkg.name}] ERROR`), `In Eleventy 3.0 \`--formats=""\` and \`formats=\` are empty template format sets. Previous versions aliased these to "*". Use \`--formats=*\` if you want to keep using that behavior in 3.0. Read more: https://github.com/11ty/eleventy/issues/3255`);
 	}
 };

src/plugin-land.js

@@ -0,0 +1,27 @@
+const chalk = require("kleur");
+const path = require("node:path");
+const fastglob = require("fast-glob");
+const pkg = require("../package.json");
+
+module.exports = function(eleventyConfig) {
+	let installedPlugins = {};
+	for(let { key, extension, aliasKey } of eleventyConfig.extensionMap) {
+		installedPlugins[key] = true;
+	}
+
+	// template formats: * or explicit pug,ejs,haml,mustache,handlebars
+	// any of these files in your project
+
+	let allRemovedKeys = "pug,ejs,haml,mustache,handlebars".split(",");
+
+	for(let removedKey of allRemovedKeys) {
+		let foundFiles = fastglob.sync(`${eleventyConfig.directories.input}**/*.${removedKey}`);
+		if(foundFiles.length > 0) {
+			if( !installedPlugins[removedKey]) {
+				console.log(chalk.red(`[${pkg.name}] ERROR`), `Found ${foundFiles.length} ${removedKey} file${foundFiles.length !== 1 ? "s" : ""} in your project but the ${removedKey} plugin was moved from core to an officially supported plugin. You will need to add the plugin for ${removedKey}, available here: https://github.com/11ty/eleventy-plugin-template-languages and you can learn more about this here: https://github.com/11ty/eleventy/issues/3124`);
+			} else {
+				console.log(chalk.green(`[${pkg.name}] PASSED`), `You have installed the ${removedKey} plugin to handle the ${foundFiles.length} ${removedKey} file${foundFiles.length !== 1 ? "s" : ""} in your project. Learn more: https://github.com/11ty/eleventy/issues/3124`);
+			}
+		}
+	}
+};