QDomDocument: Add a way to enable spacing-only text nodes

Added a parse option that can be passed to setContent(), to specify that
spacing-only text nodes must be preserved.

[ChangeLog][QtXml][QDomDocument] Spacing-only text nodes can now
be preserved by passing the ParseOption::PreserveSpacingOnlyNodes option
to setContent().

Fixes: QTBUG-104130
Fixes: QTBUG-89690
Task-number: QTBUG-90003
Change-Id: Id43730ce5b79a856c4b434d1f1d4dd7c49c25f31
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

4 files changed, 17 insertions, 8 deletions

diff --git a/src/xml/dom/qdom.cpp b/src/xml/dom/qdom.cpp
index 74ea7d1e4e..b2fcac7f1b 100644
--- a/src/xml/dom/qdom.cpp
+++ b/src/xml/dom/qdom.cpp
@@ -6221,6 +6221,8 @@ bool QDomDocument::setContent(QXmlStreamReader *reader, bool namespaceProcessing
 
     \value Default No parse options are set.
     \value UseNamespaceProcessing Namespace processing is enabled.
+    \value PreserveSpacingOnlyNodes Text nodes containing only spacing
+           characters are preserved.
 
     \sa setContent()
 */
@@ -6307,7 +6309,9 @@ bool QDomDocument::setContent(QXmlStreamReader *reader, bool namespaceProcessing
     string if the element or attribute has no prefix.
 
     Text nodes consisting only of whitespace are stripped and won't
-    appear in the QDomDocument.
+    appear in the QDomDocument. Since Qt 6.5, one can pass
+    QDomDocument::ParseOption::PreserveSpacingOnlyNodes as a parse
+    option, to specify that spacing-only text nodes must be preserved.
 
     \include qdom.cpp entity-refs
 
diff --git a/src/xml/dom/qdom.h b/src/xml/dom/qdom.h
index f4c0da1b16..390a319553 100644
--- a/src/xml/dom/qdom.h
+++ b/src/xml/dom/qdom.h
@@ -268,6 +268,7 @@ public:
     enum class ParseOption {
         Default = 0x00,
         UseNamespaceProcessing = 0x01,
+        PreserveSpacingOnlyNodes = 0x02,
     };
     Q_DECLARE_FLAGS(ParseOptions, ParseOption)
 
diff --git a/src/xml/dom/qdomhelpers.cpp b/src/xml/dom/qdomhelpers.cpp
index 2a4d4c5b3a..62258fbdfd 100644
--- a/src/xml/dom/qdomhelpers.cpp
+++ b/src/xml/dom/qdomhelpers.cpp
@@ -349,13 +349,14 @@ bool QDomParser::parseBody()
             }
             break;
         case QXmlStreamReader::Characters:
-            if (!reader->isWhitespace()) { // Skip the content consisting of only whitespaces
-                if (reader->isCDATA() || !reader->text().trimmed().isEmpty()) {
-                    if (!domBuilder.characters(reader->text().toString(), reader->isCDATA())) {
-                        domBuilder.fatalError(QDomParser::tr(
-                                "Error occurred while processing the element content"));
-                        return false;
-                    }
+            // Skip the content if it contains only spacing characters,
+            // unless it's CDATA or PreserveSpacingOnlyNodes was specified.
+            if (reader->isCDATA() || domBuilder.preserveSpacingOnlyNodes()
+                || !(reader->isWhitespace() || reader->text().trimmed().isEmpty())) {
+                if (!domBuilder.characters(reader->text().toString(), reader->isCDATA())) {
+                    domBuilder.fatalError(
+                            QDomParser::tr("Error occurred while processing the element content"));
+                    return false;
                 }
             }
             break;
diff --git a/src/xml/dom/qdomhelpers_p.h b/src/xml/dom/qdomhelpers_p.h
index 73177981b5..5a4b2207f9 100644
--- a/src/xml/dom/qdomhelpers_p.h
+++ b/src/xml/dom/qdomhelpers_p.h
@@ -56,6 +56,9 @@ public:
     void fatalError(const QString &message);
     QDomDocument::ParseResult result() const { return parseResult; }
 
+    bool preserveSpacingOnlyNodes() const
+    { return parseOptions & QDomDocument::ParseOption::PreserveSpacingOnlyNodes; }
+
 private:
     QString dtdInternalSubset(const QString &dtd);