YAML output for "0"

[szepeviktor]

Bug Report

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Describe the current, buggy behavior

When an option is "0" YAML format output is empty.
JSON output is "0"

Describe how other contributors can replicate this bug

$ wp option get blog_public --format=yaml
---

[Takshil-Kunadia]

I traced this to this code where PHP’s treatment of 0 as empty leads to an empty value being returned when 0 is passed.

This happens conceptually because Spyc expects an array as an argument here.

wp-cli/php/class-wp-cli.php

Line 1053 in 2800ad0

$value = Spyc::YAMLDump( $value, 2, 0 );

A straightforward workaround would be to cast $value to an array before passing it to Spyc, which does resolve the issue partially — though it forces non-array values to be represented as single-element arrays in the YAML output, which may not be necessarily desirable for output consistency.

Judging how JSON treats 0/falsy/''/"" An alternative approach might be to add a small elseif condition to if condition in dump. However, I am not sure about the implications of modifying such an old package tbh.

elseif (null !== $array) {
      $string .= $this->_doLiteralBlock($array,0);
}

[adityaanurag0219]

Hi 👋, I’d like to work on this issue. Thanks @Takshil-Kunadia for the helpful analysis .
My plan is to handle scalars (like 0) separately before passing to Spyc::YAMLDump, so that --format=yaml outputs 0 correctly instead of empty. I’ll also add a test case for this. Please let me know if there are any additional considerations before I start.