JSON-encode objects with no TO_JSON or stringification overload as null

[ilmari]

This matches the convert_blessed/allow_blessed behaviour of Cpanel::JSON::XS (since version 4.20, so also bump the requirement to that).

[Copilot]

Pull Request Overview

This PR updates the JSON encoding behavior for blessed objects that don't have a TO_JSON method or stringification overload. Instead of encoding them as strings, they are now encoded as null, which aligns with the convert_blessed/allow_blessed behavior in Cpanel::JSON::XS version 4.20+.

• Updates the minimum required version of Cpanel::JSON::XS from 4.09 to 4.20
• Modifies the encoding logic to check for stringification overload before falling back to string encoding
• Adds comprehensive test coverage for objects with and without stringification overloads

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
lib/Mojo/JSON.pm	Core logic change to check for stringification overload and bump version requirement
t/mojo/json.t	Adds test for object without stringification overload
t/mojo/json_xs.t	Updates version requirement and adds comprehensive tests for both stringified and null-encoded objects
lib/Mojolicious/Command/version.pm	Updates documentation to reflect new version requirement

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[Copilot]

[nitpick] The overload module is only used once in the file. Consider adding a comment explaining why it's imported at the top level rather than using it inline where needed, or move the usage to overload::Method($value, '""') directly without the import.

Suggested change

use overload ();

[Copilot]

[nitpick] This line combines multiple conditions and operations, making it difficult to read. Consider splitting this into separate conditional blocks for better clarity and maintainability.

Suggested change

	return overload::Method($value, '""') ? _encode_string($value) : 'null' unless my $sub = $value->can('TO_JSON');
	return _encode_value($value->$sub);
	my $sub = $value->can('TO_JSON');
	return _encode_value($value->$sub) if $sub;
	if (overload::Method($value, '""')) {
	return _encode_string($value);
	}
	return 'null';