feat: introduce flatten() as a more generic alternative to flattenLast()

[triceo]

No description provided.

[Copilot]

Pull request overview

This pull request introduces a new flatten() method as a more generic alternative to the existing flattenLast() method in the constraint streams API. The key difference is that flatten() preserves all original tuple elements and appends new elements from the iterable, while flattenLast() replaces the last element with items from the iterable.

Changes:

• Added flatten() methods to UniConstraintStream, BiConstraintStream, and TriConstraintStream APIs
• Implemented corresponding Bavet constraint stream classes and node classes for the new flatten operation
• Updated documentation to explain both flatten() and flattenLast(), positioning flattenLast() as a simplified version
• Refactored AbstractFlattenLastNode to remove one generic type parameter and change the abstract method signature
• Added test coverage for the new flatten() operation across Uni, Bi, and Tri constraint streams

Reviewed changes

Copilot reviewed 27 out of 27 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
score-calculation.adoc	Updated documentation to introduce flatten() first, then explain flattenLast() as a simplified alternative
UniConstraintStream.java	Added flatten() API method with BiConstraintStream return type, updated flattenLast() javadoc
BiConstraintStream.java	Added flatten() API method with TriConstraintStream return type, updated flatten/flattenLast javadoc
TriConstraintStream.java	Added flatten() API method with QuadConstraintStream return type
BavetFlattenUniConstraintStream.java	New implementation class for UniConstraintStream.flatten()
BavetFlattenBiConstraintStream.java	New implementation class for BiConstraintStream.flatten()
BavetFlattenTriConstraintStream.java	New implementation class for TriConstraintStream.flatten()
BavetAbstractUniConstraintStream.java	Added flatten() method implementation
BavetAbstractBiConstraintStream.java	Added flatten() method implementation
BavetAbstractTriConstraintStream.java	Added flatten() method implementation
BavetFlattenLastUniConstraintStream.java	Refactored to inline variables and use var
BavetFlattenLastBiConstraintStream.java	Removed unused imports, refactored to inline variables and use var
BavetFlattenLastTriConstraintStream.java	Refactored to inline variables
BavetFlattenLastQuadConstraintStream.java	Refactored to inline variables
FlattenUniNode.java	New node implementation for UniConstraintStream.flatten()
FlattenBiNode.java	New node implementation for BiConstraintStream.flatten()
FlattenTriNode.java	New node implementation for TriConstraintStream.flatten()
FlattenLastUniNode.java	Updated to match refactored AbstractFlattenLastNode
FlattenLastBiNode.java	Updated to match refactored AbstractFlattenLastNode
FlattenLastTriNode.java	Updated to match refactored AbstractFlattenLastNode
FlattenLastQuadNode.java	Updated to match refactored AbstractFlattenLastNode
AbstractFlattenLastNode.java	Refactored to remove one generic parameter and change abstract method from getEffectiveFactIn to extractIterable
FlattenLastUniNodeTest.java	Updated generic type parameters in test
AbstractUniConstraintStreamTest.java	Added flatten() test
AbstractBiConstraintStreamTest.java	Added flatten() test
AbstractTriConstraintStreamTest.java	Added flatten() test
ConstraintStreamFunctionalTest.java	Added default flatten() method to test interface

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[Copilot]

Pull request overview

Copilot reviewed 27 out of 27 changed files in this pull request and generated 3 comments.

Comments suppressed due to low confidence (1)

core/src/main/java/ai/timefold/solver/core/impl/bavet/common/AbstractFlattenNode.java:21

• The field name flattenLastStoreIndex is misleading since this class is now used for both flatten() and flattenLast() operations. Consider renaming it to something more generic like flattenStoreIndex or tupleStoreIndex to better reflect its purpose.

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[Christopher-Chianelli]

The code looks good to me; you might want to add flatten variants to

timefold-solver/core/src/test/java/ai/timefold/solver/core/impl/score/stream/common/ConstraintStreamNodeSharingTest.java

Lines 198 to 202 in 02e2c8b

	void differentParentSameFunctionFlattenLast();
	void sameParentDifferentFunctionFlattenLast();
	void sameParentSameFunctionFlattenLast();

and

timefold-solver/core/src/test/java/ai/timefold/solver/core/impl/score/stream/common/ConstraintStreamPrecomputeTest.java

Lines 24 to 26 in 02e2c8b

	void flattenLast();
	void flattenLastNewInstances();

[Copilot]

Pull request overview

Copilot reviewed 35 out of 35 changed files in this pull request and generated 1 comment.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
75.4% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud