get_plugin_data does not return License

[jkmassel]

get_plugin_data doesn't return the License field

[voldemortensen]

Adds 'License' to the default headers sent to get_file_data.

[voldemortensen]

Added unit tests to the patch.

[nacin]

I don't believe "License" is a real supported header.

[voldemortensen]

​https://wordpress.org/plugins/about/ states that the plugin must be licensed with a GPLv2 or later compatible license (we all know that).

The example readme file given to plugin authors has this header in it.
​https://wordpress.org/plugins/about/readme.txt

And the validator given to plugin authors the check their readme complains if you don't have a license specified.

While it's not technically required, mostly because if you don't specify a license its just assumed to be compatible, we might want to support it if there's that much emphasis on it.

[dd32]

The Readme Validator suggests the License field for the readme.txt file, It does this as it's designed to be used by the WordPress.org plugins directory (Even though it's not surfaced, we like to ensure that plugin authors are aware of what license they're submitting a plugin under).

get_plugin_data() is designed to get the plugin.php file headers, of which, License is not one of. WordPress hasn't used that field and has no use for it.

It's the same as WordPress not pulling out the Contributors or Requires at least fields which the readme supports.

Personally, I don't see the need for this change.

[swissspidy]

I don't see the need for this change

+1.