Adds upgrade helper for 11ty/eleventy#3302

.eleventy.js

@@ -18,6 +18,7 @@ module.exports = function(eleventyConfig) {
   eleventyConfig.addPlugin(require("./src/node-version.js"));
   eleventyConfig.addPlugin(require("./src/explicit-config-file.js"));
   eleventyConfig.addPlugin(require("./src/html-output-suffix.js"));
+  eleventyConfig.addPlugin(require("./src/alias-template-formats.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!`));

src/alias-template-formats.js

@@ -0,0 +1,22 @@
+const chalk = require("kleur");
+const pkg = require("../package.json");
+
+module.exports = function(eleventyConfig) {
+	eleventyConfig.on("eleventy.config", templateConfig => {
+		let templateFormatsActive = templateConfig.templateFormats.getTemplateFormats();
+
+		if(eleventyConfig.extensionMap.size === 0) {
+			console.log(chalk.green(`[${pkg.name}] PASSED`), `No aliases were added via \`eleventyConfig.addExtension()\`. If you had added an alias, it would need to be also added to your active template formats. Learn more about template formats: https://www.11ty.dev/docs/config/#template-formats or about this change: https://github.com/11ty/eleventy/issues/3302`);
+		} else {
+			for(let { key, extension, aliasKey } of eleventyConfig.extensionMap) {
+				if(!templateFormatsActive.includes(extension)) {
+					console.log(chalk.red(`[${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 ${extension} files in Eleventy. Learn more about template formats: https://www.11ty.dev/docs/config/#template-formats or about this change: https://github.com/11ty/eleventy/issues/3302`);
+				} else {
+					console.log(chalk.green(`[${pkg.name}] PASSED`), `\`${extension}\` is an active template format, referenced as an alias via \`eleventyConfig.addExtension()\`. Learn more about template formats: https://www.11ty.dev/docs/config/#template-formats or about this change: https://github.com/11ty/eleventy/issues/3302`);
+				}
+		}
+
+		}
+	});
+
+};

src/explicit-config-file.js

@@ -9,12 +9,15 @@ const argv = minimist(process.argv.slice(2), {
 });
 
 module.exports = function(eleventyConfig) {
-	let type = chalk.blue("NOTICE");
-
-	if(argv.config && !fs.existsSync(argv.config)) {
-		// We’ll never get here because the configuration file has to work to run the upgrade plugin.
-		type = chalk.red("ERROR");
+	if(argv.config) {
+		if(!fs.existsSync(argv.config)) {
+			// We’ll never get here because the configuration file has to work to run the upgrade plugin.
+			console.log(chalk.red(`[${pkg.name}] ERROR`), `Eleventy will fail with an error when you point \`--config\` to a configuration file that does not exist. Previous versions ran as-is (without application configuration). Read more: https://github.com/11ty/eleventy/issues/3373`);
+		} else {
+			console.log(chalk.green(`[${pkg.name}] PASSED`), `Eleventy will fail with an error when you point \`--config\` to a configuration file that does not exist. You are using \`--config\` but your configuration file _does_ exist—great! Read more: https://github.com/11ty/eleventy/issues/3373`);
+		}
+	} else {
+		console.log(chalk.green(`[${pkg.name}] PASSED`), `Eleventy will fail with an error when you point \`--config\` to a configuration file that does not exist. You are not using \`--config\`—so don’t worry about it! Read more: https://github.com/11ty/eleventy/issues/3373`);
 	}
 
-	console.log(chalk.blue(`[${pkg.name}]`), type, `Eleventy will fail with an error when you point \`--config\` to a configuration file that does not exist. Previous versions ran as-is (without application configuration). Read more: https://github.com/11ty/eleventy/issues/3373`);
 };

src/html-output-suffix.js

@@ -3,9 +3,9 @@ const pkg = require("../package.json");
 
 // https://v2-0-1.11ty.dev/docs/languages/html/#using-the-same-input-and-output-directories
 module.exports = function(eleventyConfig) {
-	eleventyConfig.on("eleventy.config", ({ config }) => {
-		if(!("htmlOutputSuffix" in config)) {
-			console.log(chalk.blue(`[${pkg.name}]`), chalk.blue(`NOTICE`), `The \`htmlOutputSuffix\` feature was removed. It doesn’t look like you were using it!`);
+	eleventyConfig.on("eleventy.config", (templateConfig) => {
+		if(!("htmlOutputSuffix" in templateConfig.config)) {
+			console.log(chalk.green(`[${pkg.name}] PASSED`), `The \`htmlOutputSuffix\` feature was removed. It doesn’t look like you were using it! Learn more: https://github.com/11ty/eleventy/issues/3327`);
 		} else {
 			console.log(chalk.red(`[${pkg.name}]`), chalk.red(`ERROR`), `The \`htmlOutputSuffix\` feature was removed. Learn more: https://github.com/11ty/eleventy/issues/3327`);
 		}

src/node-version.js

@@ -3,5 +3,5 @@ const pkg = require("../package.json");
 
 module.exports = function(eleventyConfig) {
 	// This throws an error in Eleventy core, so if we’ve made it here—we’ve passed the test.
-  console.log(chalk.green(`[${pkg.name}]`), chalk.green("PASSED"), `This project is using Node 18 or newer!`);
+  console.log(chalk.green(`[${pkg.name}]`), chalk.green("PASSED"), `You are using Node ${process.version}. Node 18 or newer is required.`);
 };