Drawing.append_def() Generates Use objects in <defs>

[g-braeunlich]

I am trying to use drawsvg.Raw to load some svg snippets into <defs> manually and use the defs later in the drawing. I am facing the following issue:

Example

import drawsvg

d = drawsvg.Drawing(10.0, 10.0)
d.append_def(drawsvg.Circle(0.0, 0.0, 1.0, id="A"))
print(d.as_svg())

Expected output

...
<defs>
<circle cx="0.0" cy="0.0" r="1.0" id="A" />
</defs>
...

Actual output

...
<defs>
<use xlink:href="#A" />
</defs>
...

My workaround:

class DefContainer(drawsvg.DrawingDef):
    def __init__(self, element):
        self.element = element

    def write_svg_element(
        self, id_map, is_duplicate, output_file, lcontext, dry_run, force_dup,
    ):
        self.element.write_svg_element(
            id_map, lambda _: False, output_file, lcontext, dry_run, force_dup
        )

d.append_def(DefContainer(drawsvg.Circle(0.0, 0.0, 1.0, id="A")))

But I guess Drawing.append_def should be changed so the above output which does not make sense cannot happen in the first place.

[cduck]

Thanks for the report. That definitely looks like a bug.

My guess is that the SVG generation code (the part that replaces multiple uses of an element with a single def and references) doesn't consider the case where you append to defs but don't use it.

[cduck]

Fixed by #134. Published version 2.4.0.