A .qetz keeps nothing QElectroTech computes in its folio files (stage D3c)

Format 3 folio files lose what building a folio computes
(QetContainer::dropComputed()): a wire's description of its ends
(element1_label, element1_name, element1_linked, terminalname1 and the
same for end 2), the content of a symbol text showing the symbol's
information or a composition of it, and -- when the project database's
index is written, every symbol with a uuid of its own -- a symbol's list
of its terminals.

What may go was found by test, not by reading: on 342 projects saved by
this version, each kind taken out of the file, the project opened and
saved: the wire ends came back in all 244 that had them, the symbol texts
in all 201, the terminal lists in 305 of 306 -- not in the file whose
symbols share a uuid (#1408), where wires find their ends by them; such a
project gets no index, so it keeps them.

Stays, for now: labels made from a formula and wire numbers made from one,
in the database (opening from the index and numbering read them), and a
table's size (the user's as much as computed).

tst_qetcontainer compares a joined document with the original less what is
computed, and computedNotKept checks a file holding both kinds (one filled
in by the test) loses them -- it fails when nothing is dropped. Through
QElectroTech, 342 projects: a .qetz opened from its index and saved as .qet
= eager = master; every folio of industrial and f2099 drawn and linked as
eager (f2099 but its 3 render-noise folios). ctest 96/96 with and without
QET_LAZY_FOLIOS=1.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

sources/container/qetcontainer.cpp

@@ -93,6 +93,19 @@ QList<QDomElement> childElements(const QDomElement &parent, const QString &tag)
 	return list;
 }
 
+	//An element and the text nodes on either side of it out of its parent,
+	//one text node left where they were, so nothing is read twice
+void removeElement(QDomElement e)
+{
+	QDomNode parent = e.parentNode();
+	QDomNode before = e.previousSibling(), after = e.nextSibling();
+	parent.removeChild(e);
+	if (before.isText() && after.isText()) {
+		before.setNodeValue(before.nodeValue() + after.nodeValue());
+		parent.removeChild(after);
+	}
+}
+
 	//The collection's symbol definitions, each to elements/<categories>/<name>
 void splitCollection(QDomDocument &document, const QDomElement &category, const QString &path,
 					 QList<QetZip::Entry> *parts, QSet<QString> *taken)
@@ -164,6 +177,49 @@ bool QetContainer::readDocument(const QByteArray &content, QDomDocument *documen
 			&& join(entries, document, error);
 }
 
+/**
+	@brief QetContainer::dropComputed
+	Take out of the folio @p diagram what QElectroTech computes when it
+	builds the folio (stage D3c): a wire's description of
+	its ends (element1_label, element1_name, element1_linked, terminalname1,
+	and the same for end 2), a symbol text's content where it shows the
+	symbol's information or a composition of it, and -- with
+	@p terminal_lists, when every symbol has a uuid of its own -- a symbol's
+	list of its terminals. Checked on 342 projects: opened and saved, each
+	comes back as it was, but the terminal lists of a file whose symbols
+	share a uuid (F100), where wires find their ends by them.
+*/
+void QetContainer::dropComputed(QDomElement diagram, bool terminal_lists)
+{
+	for (QDomElement list : childElements(diagram, QStringLiteral("conductors")))
+		for (QDomElement wire : childElements(list, QStringLiteral("conductor")))
+			for (const char *end : {"1", "2"})
+				for (const char *name : {"element%1_label", "element%1_name", "element%1_linked",
+										 "terminalname%1"})
+					wire.removeAttribute(QString::fromLatin1(name).arg(QLatin1String(end)));
+	for (QDomElement list : childElements(diagram, QStringLiteral("elements")))
+	{
+		for (QDomElement element : childElements(list, QStringLiteral("element")))
+		{
+			if (terminal_lists)
+				for (QDomElement terminals : childElements(element, QStringLiteral("terminals")))
+					removeElement(terminals);
+			for (QDomElement texts : childElements(element, QStringLiteral("dynamic_texts")))
+			{
+				for (QDomElement text : childElements(texts, QStringLiteral("dynamic_elmt_text")))
+				{
+					const QString from = text.attribute(QStringLiteral("text_from"));
+					if (from != QLatin1String("ElementInfo") && from != QLatin1String("CompositeText"))
+						continue;
+					for (QDomElement content : childElements(text, QStringLiteral("text")))
+						while (content.hasChildNodes())
+							content.removeChild(content.firstChild());
+				}
+			}
+		}
+	}
+}
+
 /**
 	@brief QetContainer::split
 	@param project : the project document, as QETProject::toXml() makes it
@@ -192,6 +248,10 @@ QList<QetZip::Entry> QetContainer::split(const QDomDocument &project, const QStr
 		//Folios, each with its pictures taken out
 	int folio = 0;
 	QMap<QString, QByteArray> pictures;   //name -> png, once each
+		//Nothing QElectroTech computes is kept (format 3)
+	for (QDomElement diagram : childElements(root, QStringLiteral("diagram")))
+		dropComputed(diagram, !index.isEmpty());
+
 	for (QDomElement diagram : childElements(root, QStringLiteral("diagram")))
 	{
 		++folio;

sources/container/qetcontainer.h

@@ -60,6 +60,8 @@ namespace QetContainer
 	bool readFolio(const QHash<QString, QByteArray> &files, const QString &file,
 				   QDomDocument *folio, QString *error = nullptr);
 
+		/// Take what QElectroTech computes out of a folio (format 3)
+	void dropComputed(QDomElement diagram, bool terminal_lists);
 		/// Parse @p xml as a .qet is read (QETProject::openFile)
 	bool parse(const QByteArray &xml, QDomDocument *document, QString *error = nullptr);
 		/// true if @p content is a zip, so a .qetz rather than a .qet