4.0.0

⚠️ Breaking changes

• A new encoder is strict by default. new XmlEncoder($extractor) now throws UnmappableValueException for a value it cannot map, instead of dropping it without a signal. The message names the property path and the type of the value. A null stays empty and a Stringable object is written as its text in both modes.
• Raised the PHP floor to ^8.4. PHP 8.3 is no longer supported.
• XmlEncoder::$nameConverter is private and read-only. It was protected. A subclass that read the property has to change.
• CamelCasePropertyNameConverter is a final read-only class. It can no longer be extended. Implement PropertyNameConverterInterface instead.

🔧 Internal

• Property hooks are read through the reflection API directly, the PHP 8.3 fallbacks are gone.
• A property with a stored value and a get hook is pinned by a test, the encoder writes what the hook returns.
• Copy-paste detection runs through the shared workflow, with jscpd pinned in package.json. Run npm ci once before the local ci:test.

🧭 Migration

• To keep dropping an unmappable value silently, pass false as the third constructor argument: new XmlEncoder($extractor, $nameConverter, false).
• Move to PHP 8.4 or newer.
• Replace a subclass of the converter by an implementation of the interface.

The 3.x line (PHP 8.3, lenient default) is maintained on the 3.x branch.