DocBook: amend e3020a6b.

Book authorship and authorship can be quite distinct. As far as I know, there is no standard way to represent book authorship in DocBook bibliographies.

autotests/export/docbook/basic.xml

@@ -424,7 +424,14 @@ I am no more code. </para>
 </personname>
 </author>
 </authorgroup>
-<!-- Several author tags in the reference. Other editor tag: fullbynames:bookauthor. Corresponding value: Michel Foucault -->
+<authorgroup>
+<othercredit class="other" otherclass="bookauthor">
+<personname>
+<firstname>Michel</firstname>
+<surname>Foucault</surname>
+</personname>
+</othercredit>
+</authorgroup>
 </biblioentry>
 <biblioentry xml:id="small">
 <title>A small paper</title>

src/BiblioInfo.cpp

@@ -1748,13 +1748,19 @@ string citationStyleToString(const CitationStyle & cs, bool const latex)
 }
 
 
-void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs, Buffer const & buf)
+void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs, Buffer const & buf,
+                                 const std::string type)
 {
 	// This function closely mimics getAuthorList, but produces DocBook instead of text.
 	// It has been greatly simplified, as the complete list of authors is always produced. No separators are required,
 	// as the output has a database-like shape.
 	// constructName has also been merged within, as it becomes really simple and leads to no copy-paste.
 
+	if (! type.empty() && (type != "author" && type != "book")) {
+		LYXERR0("ERROR! Unexpected author contribution `" << type <<"'.");
+		return;
+	}
+
 	if (authorsString.empty()) {
 		return;
 	}
@@ -1772,7 +1778,10 @@ void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs
 	auto it = authors.cbegin();
 	auto en = authors.cend();
 	for (size_t i = 0; it != en; ++it, ++i) {
-		xs << xml::StartTag("author");
+		const std::string tag = (type.empty() || type == "author") ? "author" : "othercredit";
+		const std::string attr = (type == "book") ? R"(class="other" otherclass="bookauthor")" : "";
+
+		xs << xml::StartTag(tag, attr);
 		xs << xml::CR();
 		xs << xml::StartTag("personname");
 		xs << xml::CR();
@@ -1812,7 +1821,7 @@ void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs
 
 		xs << xml::EndTag("personname");
 		xs << xml::CR();
-		xs << xml::EndTag("author");
+		xs << xml::EndTag(tag);
 		xs << xml::CR();
 
 		// Could add an affiliation after <personname>, but not stored in BibTeX.

src/BiblioInfo.h

@@ -37,7 +37,10 @@ CitationStyle citationStyleFromString(std::string const & latex_str,
 std::string citationStyleToString(CitationStyle const &, bool const latex = false);
 
 /// Transforms the information about authors into a <authorgroup> (directly written to a XMLStream).
-void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs, Buffer const & buf);
+/// Type: "author" or empty means author of the entry (article, book, etc.); "book" means author of the book
+/// (but not necessarily of this entry in particular).
+void authorsToDocBookAuthorGroup(docstring const & authorsString, XMLStream & xs, Buffer const & buf,
+								 std::string type);
 
 
 /// Class to represent information about a BibTeX or

src/insets/InsetBibtex.cpp

@@ -1402,29 +1402,15 @@ void InsetBibtex::docbook(XMLStream & xs, OutputParams const &) const
 
 			// <authorgroup>
 			// Example: http://tdg.docbook.org/tdg/5.1/authorgroup.html
-			if (hasTag("fullnames:author") || hasTag("fullbynames:bookauthor")) {
+			// Perform full parsing of the BibTeX string, dealing with the many corner cases that might
-				// If several author tags are present, only output one.
+			// be encountered.
-				const docstring authorName = getTag(
+			if (hasTag("fullnames:author")) {
-						hasTag("fullnames:author") ? "fullnames:author" : "fullbynames:bookauthor");
+				authorsToDocBookAuthorGroup(getTag("fullnames:author"), xs, buffer(), "author");
-
+				eraseTag("fullnames:author");
-				// Perform full parsing of the BibTeX string, dealing with the many corner cases that might
+			}
-				// be encountered.
+			if (hasTag("fullbynames:bookauthor")) {
-				authorsToDocBookAuthorGroup(authorName, xs, buffer());
+				authorsToDocBookAuthorGroup(getTag("fullbynames:bookauthor"), xs, buffer(), "book");
-
+				eraseTag("fullbynames:bookauthor");
-				if (hasTag("fullnames:author") && hasTag("fullbynames:bookauthor")) {
-					xs << XMLStream::ESCAPE_NONE <<
-					   from_utf8("<!-- Several author tags in the reference. Other editor tag: ") +
-					   from_utf8("fullbynames:bookauthor. Corresponding value: ") +
-					   getTag("fullbynames:bookauthor") + from_utf8(" -->\n");
-				}
-
-				// Erase all author tags that might be present, even if only one is output.
-				if (hasTag("fullnames:author")) {
-					eraseTag("fullnames:author");
-				}
-				if (hasTag("fullbynames:bookauthor")) {
-					eraseTag("fullbynames:bookauthor");
-				}
 			}
 
 			// <editor>