Only addPlugin once

eleventy.config.js

@@ -1,6 +1,6 @@
 const pkg = require("./package.json");
 const shortcodesPlugin = require("./eleventy.shortcodes.js");
-// const debug = require("debug")("Eleventy:Bundle");
+const debug = require("debug")("Eleventy:Bundle");
 
 function normalizeOptions(options) {
 	let shortcodes = Object.assign({
@@ -23,7 +23,9 @@ function normalizeOptions(options) {
 	return options;
 }
 
-module.exports = function(eleventyConfig, options = {}) {
+let hasExecuted = false;
+
+function eleventyBundlePlugin(eleventyConfig, options = {}) {
 	try {
 		eleventyConfig.versionCheck(pkg["11ty"].compatibility);
 	} catch(e) {
@@ -32,5 +34,16 @@ module.exports = function(eleventyConfig, options = {}) {
 
 	options = normalizeOptions(options);
 
-	eleventyConfig.addPlugin(shortcodesPlugin, options);
-};
+	eleventyConfig.on("eleventy.before", () => {
+		hasExecuted = false;
+	});
+
+	if(hasExecuted) {
+		debug("Warning: You can only addPlugin @11ty/eleventy-plugin-bundle once per project. Subsequent adds are ignored.");
+	} else {
+		hasExecuted = true;
+		shortcodesPlugin(eleventyConfig, options);
+	}
+};
+
+module.exports = eleventyBundlePlugin;

eleventy.shortcodes.js

@@ -17,7 +17,7 @@ module.exports = function(eleventyConfig, options = {}) {
 			}
 
 			if(addShortcodeName) {
-				eleventyConfig.addPairedShortcode(addShortcodeName, function addContent(content, bucket, urlOverride) {		
+				eleventyConfig.addPairedShortcode(addShortcodeName, function addContent(content, bucket, urlOverride) {
 					let url = urlOverride || this.page.url;
 					managers[name].addToPage(url, content, bucket);
 					return "";
@@ -77,4 +77,4 @@ module.exports = function(eleventyConfig, options = {}) {
 			}
 		});
 	}
-};
+};

package.json

@@ -4,7 +4,7 @@
 	"description": "Little bundles of code, little bundles of joy.",
 	"main": "eleventy.config.js",
 	"scripts": {
-		"sample": "npx @11ty/eleventy --config=sample/sample-config.js --input=sample",
+		"sample": "DEBUG=Eleventy:Bundle npx @11ty/eleventy --config=sample/sample-config.js --input=sample",
 		"test": "npx ava"
 	},
 	"publishConfig": {

sample/sample-config.js

@@ -1,3 +1,6 @@
+const bundlePlugin = require("../eleventy.config.js");
+
 module.exports = function(eleventyConfig) {
-	eleventyConfig.addPlugin(require("../eleventy.config.js"));
-};
+	eleventyConfig.addPlugin(bundlePlugin);
+	eleventyConfig.addPlugin(bundlePlugin);
+};