Strip unnecessary whitespace from Stanza elements

strophe · Dec 29, 2024 · 9b643a4 · 9b643a4
1 parent 715a036
commit 9b643a4
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Showing 5 changed files with 38 additions and 2 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Strophe.js Change Log
 
+## Version 3.1.1 - (Unreleased)
+
+- Strip unnecessary whitespace from `Stanza` elements
+- Bugfix. Handle `null` and `undefined` values inside `stx` tagged template literals.
+
 ## Version 3.1.0 - (2024-12-16)
 
 - **Security Fix**: Escape values passed to the `stx` tagged template literal

diff --git a/src/stanza.js b/src/stanza.js
@@ -1,6 +1,6 @@
 import Builder from './builder.js';
 import log from './log.js';
-import { getFirstElementChild, getParserError, xmlHtmlNode, xmlescape } from './utils.js';
+import { getFirstElementChild, getParserError, stripWhitespace, xmlHtmlNode, xmlescape } from './utils.js';
 
 /**
  * A Stanza represents a XML element used in XMPP (commonly referred to as stanzas).
@@ -61,7 +61,7 @@ export class Stanza extends Builder {
             throw new Error(`Parser Error: ${parserError}`);
         }
 
-        const node = getFirstElementChild(doc);
+        const node = stripWhitespace(getFirstElementChild(doc));
         if (
             ['message', 'iq', 'presence'].includes(node.nodeName.toLowerCase()) &&
             node.namespaceURI !== 'jabber:client' &&

diff --git a/src/types/index.d.ts b/src/types/index.d.ts
@@ -161,6 +161,7 @@ export const Strophe: {
     }): void;
     xmlGenerator(): Document;
     xmlTextNode(text: string): Text;
+    stripWhitespace(stanza: Element): Element;
     xmlHtmlNode(text: string): XMLDocument;
     getParserError(doc: XMLDocument): string | null;
     getFirstElementChild(el: XMLDocument): Element;

diff --git a/src/types/utils.d.ts b/src/types/utils.d.ts
@@ -57,6 +57,11 @@ export function xmlGenerator(): Document;
  * @return {Text} - A new XML DOM text node.
  */
 export function xmlTextNode(text: string): Text;
+/**
+ * @param {Element} stanza
+ * @return {Element}
+ */
+export function stripWhitespace(stanza: Element): Element;
 /**
  * Creates an XML DOM node.
  * @param {string} text - The contents of the XML element.

diff --git a/src/utils.js b/src/utils.js
@@ -184,6 +184,31 @@ export function xmlTextNode(text) {
     return xmlGenerator().createTextNode(text);
 }
 
+/**
+ * @param {Element} stanza
+ * @return {Element}
+ */
+export function stripWhitespace(stanza) {
+    const childNodes = Array.from(stanza.childNodes);
+    if (childNodes.length === 1 && childNodes[0].nodeType === ElementType.TEXT) {
+        // If the element has only one child and it's a text node, we assume
+        // it's significant and don't remove it, even if it's only whitespace.
+        return stanza;
+    }
+    childNodes.forEach((node) => {
+        if (node.nodeName.toLowerCase() === 'body') {
+            // We don't remove anything inside <body> elements
+            return;
+        }
+        if (node.nodeType === ElementType.TEXT && !(/\S/).test(node.nodeValue)) {
+            stanza.removeChild(node);
+        } else if (node.nodeType === ElementType.NORMAL) {
+            stripWhitespace(/** @type {Element} */ (node));
+        }
+    });
+    return stanza;
+}
+
 /**
  * Creates an XML DOM node.
  * @param {string} text - The contents of the XML element.