HHH-17375 Shorthand bracket syntax for array slicing

documentation/src/main/asciidoc/userguide/chapters/query/hql/QueryLanguage.adoc

@@ -1458,14 +1458,26 @@ include::{array-example-dir-hql}/ArrayRemoveIndexTest.java[tags=hql-array-remove
 [[hql-array-slice-functions]]
 ===== `array_slice()`
 
-Returns the sub-array as specified by the given start and end index. Returns `null` if any of the arguments is `null`
+Returns the sub-array as specified by the given 1-based inclusive start and end index. Returns `null` if any of the arguments is `null`
 and also if the index is out of bounds.
 
-[[hql-array-remove-index-example]]
+[[hql-array-slice-example]]
 ====
 [source, JAVA, indent=0]
 ----
-include::{array-example-dir-hql}/ArrayRemoveIndexTest.java[tags=hql-array-remove-index-example]
+include::{array-example-dir-hql}/ArraySliceTest.java[tags=hql-array-slice-example]
+----
+====
+
+Alternatively, it's also possible to slice an array by specifying the lower and upper bound,
+separated by a colon, as index in the bracket array index syntax `array[lowerIndex:upperIndex]`.
+This is syntax sugar that translates to the `array_slice` function.
+
+[[hql-array-slice-hql-example]]
+====
+[source, JAVA, indent=0]
+----
+include::{array-example-dir-hql}/ArraySliceTest.java[tags=hql-array-slice-hql-example]
 ----
 ====
 

hibernate-core/src/main/antlr/org/hibernate/grammars/hql/HqlParser.g4

@@ -438,9 +438,11 @@ syntacticDomainPath
 	| collectionValueNavigablePath
 	| mapKeyNavigablePath
 	| simplePath indexedPathAccessFragment
+	| simplePath slicedPathAccessFragment
 	| toOneFkReference
 	| function pathContinuation
 	| function indexedPathAccessFragment pathContinuation?
+	| function slicedPathAccessFragment
 	;
 
 /**
@@ -463,6 +465,13 @@ indexedPathAccessFragment
 	: LEFT_BRACKET expression RIGHT_BRACKET (DOT generalPathFragment)?
 	;
 
+/**
+ * The slice operator to obtain elements between the lower and upper bound.
+ */
+slicedPathAccessFragment
+	: LEFT_BRACKET expression COLON expression RIGHT_BRACKET
+	;
+
 /**
  * A 'treat()' function that "breaks" a path expression
  */

hibernate-core/src/main/java/org/hibernate/query/hql/internal/SemanticQueryBuilder.java

@@ -5205,6 +5205,20 @@ public class SemanticQueryBuilder<R> extends HqlParserBaseVisitor<Object> implem
 			return visitToOneFkReference( ctx.toOneFkReference() );
 		}
 		else if ( ctx.function() != null ) {
+			final HqlParser.SlicedPathAccessFragmentContext slicedFragmentsCtx = ctx.slicedPathAccessFragment();
+			if ( slicedFragmentsCtx != null ) {
+				final List<HqlParser.ExpressionContext> slicedFragments = slicedFragmentsCtx.expression();
+				return getFunctionDescriptor( "array_slice" ).generateSqmExpression(
+						List.of(
+								(SqmTypedNode<?>) visitFunction( ctx.function() ),
+								(SqmTypedNode<?>) slicedFragments.get( 0 ).accept( this ),
+								(SqmTypedNode<?>) slicedFragments.get( 1 ).accept( this )
+						),
+						null,
+						creationContext.getQueryEngine()
+				);
+			}
+			else {
 				return visitPathContinuation(
 						visitIndexedPathAccessFragment(
 								(SemanticPathPart) visitFunction( ctx.function() ),
@@ -5213,9 +5227,22 @@ public class SemanticQueryBuilder<R> extends HqlParserBaseVisitor<Object> implem
 						ctx.pathContinuation()
 				);
 			}
+		}
 		else if ( ctx.simplePath() != null && ctx.indexedPathAccessFragment() != null ) {
 			return visitIndexedPathAccessFragment( visitSimplePath( ctx.simplePath() ), ctx.indexedPathAccessFragment() );
 		}
+		else if ( ctx.simplePath() != null && ctx.slicedPathAccessFragment() != null ) {
+			final List<HqlParser.ExpressionContext> slicedFragments = ctx.slicedPathAccessFragment().expression();
+			return getFunctionDescriptor( "array_slice" ).generateSqmExpression(
+					List.of(
+							(SqmTypedNode<?>) visitSimplePath( ctx.simplePath() ),
+							(SqmTypedNode<?>) slicedFragments.get( 0 ).accept( this ),
+							(SqmTypedNode<?>) slicedFragments.get( 1 ).accept( this )
+					),
+					null,
+					creationContext.getQueryEngine()
+			);
+		}
 		else {
 			throw new ParsingException( "Illegal domain path '" + ctx.getText() + "'" );
 		}

hibernate-core/src/test/java/org/hibernate/orm/test/function/array/ArraySliceTest.java

@@ -139,4 +139,21 @@ public class ArraySliceTest {
 		} );
 	}
 
+	@Test
+	public void testSliceSyntax(SessionFactoryScope scope) {
+		scope.inSession( em -> {
+			//tag::hql-array-slice-hql-example[]
+			List<Tuple> results = em.createQuery( "select e.id, e.theArray[1:1] from EntityWithArrays e order by e.id", Tuple.class )
+					.getResultList();
+			//end::hql-array-slice-hql-example[]
+			assertEquals( 3, results.size() );
+			assertEquals( 1L, results.get( 0 ).get( 0 ) );
+			assertArrayEquals( new String[0], results.get( 0 ).get( 1, String[].class ) );
+			assertEquals( 2L, results.get( 1 ).get( 0 ) );
+			assertArrayEquals( new String[] { "abc" }, results.get( 1 ).get( 1, String[].class ) );
+			assertEquals( 3L, results.get( 2 ).get( 0 ) );
+			assertNull( results.get( 2 ).get( 1, String[].class ) );
+		} );
+	}
+
 }