OpenDocument writer: Allow references for internal links (#6774)

This commit adds two extensions to the OpenDocument writer,
`xrefs_name` and `xrefs_number`.

Links to headings, figures and tables inside the document are
substituted with cross-references that will use the name or caption
of the referenced item for `xrefs_name` or the number for `xrefs_number`.

For the `xrefs_number` to be useful heading numbers must be enabled
in the generated document and table and figure captions must be enabled using for example the `native_numbering` extension.

In order for numbers and reference text to be updated the generated
document must be refreshed.

Co-authored-by: Nils Carlson <nils.carlson@ludd.ltu.se>

1 files changed, 63 insertions, 0 deletions

diff --git a/test/command/6774.md b/test/command/6774.md
new file mode 100644
index 000000000..66549c0f2
--- /dev/null
+++ b/test/command/6774.md
@@ -0,0 +1,63 @@
+```
+% pandoc -f native -t opendocument --quiet
+[Header 1 ("chapter1",[],[]) [Str "The",Space,Str "Chapter"]
+,Para [Str "Chapter",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "The",Space,Str "Chapter"] ("#chapter1","")]]
+^D
+<text:h text:style-name="Heading_20_1" text:outline-level="1"><text:bookmark-start text:name="chapter1" />The
+Chapter<text:bookmark-end text:name="chapter1" /></text:h>
+<text:p text:style-name="First_20_paragraph">Chapter 1 references
+<text:a xlink:type="simple" xlink:href="#chapter1" office:name=""><text:span text:style-name="Definition">The
+Chapter</text:span></text:a></text:p>
+```
+```
+% pandoc -f native -t opendocument+xrefs_name --quiet
+[Header 1 ("chapter1",[],[]) [Str "The",Space,Str "Chapter"]
+,Para [Str "Chapter",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "The",Space,Str "Chapter"] ("#chapter1","")]
+,Para [Image ("lalune",[],[]) [Str "lalune"] ("lalune.jpg","fig:Voyage dans la Lune")]
+,Para [Str "Image",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "La",Space,Str "Lune"] ("#lalune","")]]
+^D
+<text:h text:style-name="Heading_20_1" text:outline-level="1"><text:bookmark-start text:name="chapter1" />The
+Chapter<text:bookmark-end text:name="chapter1" /></text:h>
+<text:p text:style-name="First_20_paragraph">Chapter 1 references
+<text:bookmark-ref text:reference-format="text" text:ref-name="chapter1">The
+Chapter</text:bookmark-ref></text:p>
+<text:p text:style-name="FigureWithCaption"><draw:frame draw:name="img1"><draw:image xlink:href="lalune.jpg" xlink:type="simple" xlink:show="embed" xlink:actuate="onLoad" /></draw:frame></text:p>
+<text:p text:style-name="FigureCaption">lalune</text:p>
+<text:p text:style-name="Text_20_body">Image 1 references
+<text:sequence-ref text:reference-format="caption" text:ref-name="lalune">La
+Lune</text:sequence-ref></text:p>
+```
+```
+% pandoc -f native -t opendocument+xrefs_number --quiet
+[Header 1 ("chapter1",[],[]) [Str "The",Space,Str "Chapter"]
+,Para [Str "Chapter",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "The",Space,Str "Chapter"] ("#chapter1","")]
+,Para [Image ("lalune",[],[]) [Str "lalune"] ("lalune.jpg","fig:Voyage dans la Lune")]
+,Para [Str "Image",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "La",Space,Str "Lune"] ("#lalune","")]]
+^D
+<text:h text:style-name="Heading_20_1" text:outline-level="1"><text:bookmark-start text:name="chapter1" />The
+Chapter<text:bookmark-end text:name="chapter1" /></text:h>
+<text:p text:style-name="First_20_paragraph">Chapter 1 references
+<text:bookmark-ref text:reference-format="number" text:ref-name="chapter1"></text:bookmark-ref></text:p>
+<text:p text:style-name="FigureWithCaption"><draw:frame draw:name="img1"><draw:image xlink:href="lalune.jpg" xlink:type="simple" xlink:show="embed" xlink:actuate="onLoad" /></draw:frame></text:p>
+<text:p text:style-name="FigureCaption">lalune</text:p>
+<text:p text:style-name="Text_20_body">Image 1 references
+<text:sequence-ref text:reference-format="value" text:ref-name="lalune"></text:sequence-ref></text:p>
+```
+```
+% pandoc -f native -t opendocument+xrefs_number+xrefs_name --quiet
+[Header 1 ("chapter1",[],[]) [Str "The",Space,Str "Chapter"]
+,Para [Str "Chapter",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "The",Space,Str "Chapter"] ("#chapter1","")]
+,Para [Image ("lalune",[],[]) [Str "lalune"] ("lalune.jpg","fig:Voyage dans la Lune")]
+,Para [Str "Image",Space,Str "1",Space,Str "references",Space,Link ("",[],[]) [Str "La",Space,Str "Lune"] ("#lalune","")]]
+^D
+<text:h text:style-name="Heading_20_1" text:outline-level="1"><text:bookmark-start text:name="chapter1" />The
+Chapter<text:bookmark-end text:name="chapter1" /></text:h>
+<text:p text:style-name="First_20_paragraph">Chapter 1 references
+<text:bookmark-ref text:reference-format="number" text:ref-name="chapter1"></text:bookmark-ref><text:s /><text:bookmark-ref text:reference-format="text" text:ref-name="chapter1">The
+Chapter</text:bookmark-ref></text:p>
+<text:p text:style-name="FigureWithCaption"><draw:frame draw:name="img1"><draw:image xlink:href="lalune.jpg" xlink:type="simple" xlink:show="embed" xlink:actuate="onLoad" /></draw:frame></text:p>
+<text:p text:style-name="FigureCaption">lalune</text:p>
+<text:p text:style-name="Text_20_body">Image 1 references
+<text:sequence-ref text:reference-format="value" text:ref-name="lalune"></text:sequence-ref><text:s /><text:sequence-ref text:reference-format="caption" text:ref-name="lalune">La
+Lune</text:sequence-ref></text:p>
+```