Add removeEmptyLinePlugin to clean empty lines from HTML attributes

bbcode-src/index.js

@@ -2,6 +2,7 @@ import bbob from "@bbob/core";
 import { render } from "@bbob/html";
 import { lineBreakPlugin } from "./plugins/lineBreak";
 import { preserveWhitespace } from "./plugins/preserveWhitespace";
+import { removeEmptyLinePlugin } from "./plugins/removeEmptyLinesInAttr";
 import { availableTags, preset, preventParsing } from "./preset";
 import { postprocess } from "./utils/postprocess";
 import { preprocessRaw } from "./utils/preprocess";
@@ -25,7 +26,7 @@ export const RpNBBCode = (code, opts) => {
   if (opts.preserveWhitespace) {
     plugins.push(preserveWhitespace());
   }
-  plugins.push(lineBreakPlugin());
+  plugins.push(lineBreakPlugin(), removeEmptyLinePlugin);
   const [preprocessed, preprocessedData] = preprocessRaw(code);
   return bbob(plugins).process(preprocessed, {
     render,

bbcode-src/plugins/removeEmptyLinesInAttr.js

@@ -0,0 +1,28 @@
+import { isTagNode } from "@bbob/plugin-helper";
+
+const CONSECUTIVE_NEWLINE_REGEX = /\n{2,}/gm;
+
+/**
+ * Removes empty lines from a string
+ * @param {string} text
+ */
+const removeEmptyLines = (text) => {
+  return text.replace(CONSECUTIVE_NEWLINE_REGEX, "\n");
+};
+
+/**
+ * Removes empty lines from attributes
+ * @type {import('@bbob/types').BBobPluginFunction}
+ */
+export const removeEmptyLinePlugin = (tree) => {
+  return tree.walk((node) => {
+    if (isTagNode(node) && node.attrs) {
+      Object.keys(node.attrs).forEach((key) => {
+        if (typeof node.attrs[key] === "string") {
+          node.attrs[key] = removeEmptyLines(node.attrs[key]);
+        }
+      });
+    }
+    return node;
+  });
+};