Shortcode attributes named 0 are ignored

[ourous]

Shortcode attributes in the form 0=... are not picked up during parsing.
This is because the parser checks for an empty name with empty(..), which also returns true for the string '0'.

[SergeyBiryukov]

Hi there, welcome to WordPress Trac! Thanks for the report, I was able to reproduce the issue.

Looks like this happens because the shortcode_parse_atts() function has some checks like ! empty( $m[1] ), which should perhaps be replaced with '' !== $m[1].