The mapper is now more type-sensitive and will fail in the following
situations:
- When a value does not match exactly the awaited scalar type, for
instance a string `"42"` given to a node that awaits an integer.
- When unnecessary array keys are present, for instance mapping an array
`['foo' => …, 'bar' => …, 'baz' => …]` to an object that needs only
`foo` and `bar`.
- When permissive types like `mixed` or `object` are encountered.
These limitations can be bypassed by enabling the flexible mode:
```php
(new \CuyZ\Valinor\MapperBuilder())
->flexible()
->mapper();
->map('array{foo: int, bar: bool}', [
'foo' => '42', // Will be cast from `string` to `int`
'bar' => 'true', // Will be cast from `string` to `bool`
'baz' => '…', // Will be ignored
]);
```
When using this library for a provider application — for instance an API
endpoint that can be called with a JSON payload — it is recommended to
use the strict mode. This ensures that the consumers of the API provide
the exact awaited data structure, and prevents unknown values to be
passed.
When using this library as a consumer of an external source, it can make
sense to enable the flexible mode. This allows for instance to convert
string numeric values to integers or to ignore data that is present in
the source but not needed in the application.
---
All these changes led to a new check that runs on all registered object
constructors. If a collision is found between several constructors that
have the same signature (the same parameter names), an exception will be
thrown.
```php
final class SomeClass
{
public static function constructorA(string $foo, string $bar): self
{
// …
}
public static function constructorB(string $foo, string $bar): self
{
// …
}
}
(new \CuyZ\Valinor\MapperBuilder())
->registerConstructor(
SomeClass::constructorA(...),
SomeClass::constructorB(...),
)
->mapper();
->map(SomeClass::class, [
'foo' => 'foo',
'bar' => 'bar',
]);
// Exception: A collision was detected […]
```
The cache implementation that was previously injected in the mapper
builder must now be manually injected. This gives better control on when
the cache should be enabled, especially depending on which environment
the application is running.
The library provides a cache implementation out of the box, which saves
cache entries into the file system.
It is also possible to use any PSR-16 compliant implementation, as long
as it is capable of caching the entries handled by the library.
```php
$cache = new \CuyZ\Valinor\Cache\FileSystemCache('path/to/cache-dir');
(new \CuyZ\Valinor\MapperBuilder())
->withCache($cache)
->mapper()
->map(SomeClass::class, [/* … */]);
```
Previously, the method `TreeMapper::map` would allow mapping only to an
object. It is now possible to map to any type handled by the library.
It is for instance possible to map to an array of objects:
```php
$objects = (new \CuyZ\Valinor\MapperBuilder())->mapper()->map(
'array<' . SomeClass::class . '>',
[/* … */]
);
```
For simple use-cases, an array shape can be used:
```php
$array = (new \CuyZ\Valinor\MapperBuilder())->mapper()->map(
'array{foo: string, bar: int}',
[/* … */]
);
echo strtolower($array['foo']);
echo $array['bar'] * 2;
```
This new feature changes the possible behaviour of the mapper, meaning
static analysis tools need help to understand the types correctly. An
extension for PHPStan and a plugin for Psalm are now provided and can be
included in a project to automatically increase the type coverage.