fix: Read from STDIN

[kesara]

Fixes #36

[jennifer-richards]

One potentially important comment inline. Requesting changes because I think that's a bug, but it depends on what input you intend to accept.

Also... Rather than inserting a cleanup function in every code path, I think you could put the call to delete_tempfile() in a finally: block at the end of your try. However, you might consider getting fancy and using ExitStack from contextlib:

from contextlib import ExitStack

# ... setup stuff ...

with ExitStack() as stack:
    if len(args) < 1:
        tmp_file = stack.enter_context(NamedTemporaryFile(delete_on_close=False, mode="w+t"))  # or w+b
        data = #...
        tmp_file.write(data)
        tmp_file.close()
        source = tmp_file.name
    else:
        source = args[0]
        # test existence...
    # ... rest of the processing, minus the delete_tempfile() calls

This will conditionally open a context and let NamedTemporaryFile do the deletion magic (note the significant change from delete=False to delete_on_close=False in its call).

[jennifer-richards]

Just a minor suggestion to consider.

I have slight misgivings about the separate calls to process_svg() in the two paths and the introduction of version-dependent code paths. That's only on the basis of slippery slopes toward complexity, though, so I don't object.

[jennifer-richards]

One last tweak needed. (You could also take the post-tmp_file-write stuff out of the with block instead of explicitly closing, but I think that's ok either way.)

[kesara]

One last tweak needed. (You could also take the post-tmp_file-write stuff out of the with block instead of explicitly closing, but I think that's ok either way.)

yeah, but no gains or adverse effects either way?