Add the keep methods to the StepInterface

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [2.0.0] - 2024-x-x
 ### Changed
 * __BREAKING__: Removed methods `BaseStep::addToResult()`, `BaseStep::addLaterToResult()`, `BaseStep::addsToOrCreatesResult()`, `BaseStep::createsResult()`, and `BaseStep::keepInputData()`. These methods were deprecated in v1.8.0 and should be replaced with `Step::keep()`, `Step::keepAs()`, `Step::keepFromInput()`, and `Step::keepInputAs()`.
+* __BREAKING__: Added the following keep methods to the `StepInterface`: `StepInterface::keep()`, `StepInterface::keepAs()`, `StepInterface::keepFromInput()`, `StepInterface::keepInputAs()`, as well as `StepInterface::keepsAnything()`, `StepInterface::keepsAnythingFromInputData()` and `StepInterface::keepsAnythingFromOutputData()`. If you have a class that implements this interface without extending `Step` (or `BaseStep`), you will need to implement these methods yourself. However, it is strongly recommended to extend `Step` instead.
 * __BREAKING__: With the removal of the `addToResult()` method, the library no longer uses `toArrayForAddToResult()` methods on output objects. Instead, please use `toArrayForResult()`. Consequently, `RespondedRequest::toArrayForAddToResult()` has been renamed to `RespondedRequest::toArrayForResult()`.
 * __BREAKING__: Removed the `result` and `addLaterToResult` properties from `Io` objects (`Input` and `Output`). These properties were part of the `addToResult` feature and are now removed. Instead, use the `keep` property where kept data is added.
 * __BREAKING__: The signature of the `Crawler::addStep()` method has changed. You can no longer provide a result key as the first parameter. Previously, this key was passed to the `Step::addToResult()` method internally. Now, please handle this call yourself.

src/Steps/StepInterface.php

@@ -18,6 +18,26 @@ public function addLogger(LoggerInterface $logger): static;
      */
     public function invokeStep(Input $input): Generator;
 
+    /**
+     * @param string|string[]|null $keys
+     */
+    public function keep(string|array|null $keys = null): static;
+
+    public function keepAs(string $key): static;
+
+    /**
+     * @param string|string[]|null $keys
+     */
+    public function keepFromInput(string|array|null $keys = null): static;
+
+    public function keepInputAs(string $key): static;
+
+    public function keepsAnything(): bool;
+
+    public function keepsAnythingFromInputData(): bool;
+
+    public function keepsAnythingFromOutputData(): bool;
+
     public function useInputKey(string $key): static;
 
     public function uniqueInputs(?string $key = null): static;