Support Arithmetic function INDEX

docs/en/jpql-with-kotlin-jdsl/expressions.md

@@ -225,6 +225,7 @@ locate("Book", path(Book::title))
 * CEILING (ceiling)
 * EXP (exp)
 * FLOOR (floor)
+* INDEX (index)
 * LN (ln)
 * ROUND (round)
 * SIGN (sign)
@@ -240,6 +241,8 @@ exp(path(Book::price))
 
 floor(path(Book::price))
 
+index(path(Book::authors))
+
 ln(path(Book::price))
 
 round(path(Book::price), 2)
@@ -255,7 +258,6 @@ sqrt(path(Book::price))
 |----------|--------------|
 | MOD      | not yet      |
 | POWER    | not yet      |
-| INDEX    | not yet      |
 
 ### Datetime functions
 

docs/ko/jpql-with-kotlin-jdsl/expressions.md

@@ -221,6 +221,7 @@ locate("Book", path(Book::title))
 * CEILING (ceiling)
 * EXP (exp)
 * FLOOR (floor)
+* INDEX (index)
 * LN (ln)
 * ROUND (round)
 * SIGN (sign)
@@ -236,6 +237,8 @@ exp(path(Book::price))
 
 floor(path(Book::price))
 
+index(path(Book::authors))
+
 ln(path(Book::price))
 
 round(path(Book::price), 2)
@@ -251,7 +254,6 @@ sqrt(path(Book::price))
 |----------|--------------|
 | MOD      | not yet      |
 | POWER    | not yet      |
-| INDEX    | not yet      |
 
 ### Datetime functions
 

dsl/jpql/src/main/kotlin/com/linecorp/kotlinjdsl/dsl/jpql/Jpql.kt

@@ -602,6 +602,22 @@ open class Jpql : JpqlDsl {
         return Expressions.floor(value.toExpression())
     }
 
+    /**
+     * Creates an expression that represents the index of the value in an ordered list.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Any, V, S : Collection<V>> index(expr: KProperty1<T, @Exact S>): Expression<Int> {
+        return Expressions.index(Paths.path(expr))
+    }
+
+    /**
+     * Creates an expression that represents the index of the value in an ordered list.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T, S : Collection<T>> index(path: Pathable<S>): Expression<Int> {
+        return Expressions.index(path.toPath())
+    }
+
     /**
      * Creates an expression that represents the natural logarithm of value.
      */

dsl/jpql/src/test/kotlin/com/linecorp/kotlinjdsl/dsl/jpql/expression/IndexDslTest.kt

@@ -0,0 +1,47 @@
+package com.linecorp.kotlinjdsl.dsl.jpql.expression
+
+import com.linecorp.kotlinjdsl.dsl.jpql.entity.book.Book
+import com.linecorp.kotlinjdsl.dsl.jpql.queryPart
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expression
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expressions
+import com.linecorp.kotlinjdsl.querymodel.jpql.path.Paths
+import org.assertj.core.api.WithAssertions
+import org.junit.jupiter.api.Test
+
+class IndexDslTest : WithAssertions {
+    private val expression1 = Paths.path(Book::authors)
+
+    @Test
+    fun `index() with a property`() {
+        // when
+        val expression = queryPart {
+            index(Book::authors)
+        }.toExpression()
+
+        val actual: Expression<Int> = expression // for type check
+
+        // then
+        val expected = Expressions.index(
+            path = Paths.path(Book::authors),
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `index() with a expression`() {
+        // when
+        val expression = queryPart {
+            index(expression1)
+        }.toExpression()
+
+        val actual: Expression<Int> = expression // for type check
+
+        // then
+        val expected = Expressions.index(
+            path = expression1,
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+}

query-model/jpql/src/main/kotlin/com/linecorp/kotlinjdsl/querymodel/jpql/expression/Expressions.kt

@@ -51,6 +51,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlUpper
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlValue
 import com.linecorp.kotlinjdsl.querymodel.jpql.path.Path
 import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.Predicate
+import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.impl.JpqlIndex
 import com.linecorp.kotlinjdsl.querymodel.jpql.select.SelectQuery
 import com.linecorp.kotlinjdsl.querymodel.jpql.select.impl.JpqlSelectQuery
 import java.math.BigDecimal
@@ -251,6 +252,14 @@ object Expressions {
         return JpqlFloor(value)
     }
 
+    /**
+     * Creates an expression that represents the index of the value in an ordered list.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T, S : Collection<T>> index(path: Path<S>): Expression<Int> {
+        return JpqlIndex(path)
+    }
+
     /**
      * Creates an expression that represents the natural logarithm of the value.
      */

query-model/jpql/src/main/kotlin/com/linecorp/kotlinjdsl/querymodel/jpql/predicate/impl/JpqlIndex.kt

@@ -0,0 +1,10 @@
+package com.linecorp.kotlinjdsl.querymodel.jpql.predicate.impl
+
+import com.linecorp.kotlinjdsl.Internal
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expression
+import com.linecorp.kotlinjdsl.querymodel.jpql.path.Path
+
+@Internal
+data class JpqlIndex<T, S : Collection<T>>internal constructor(
+    val path: Path<S>,
+) : Expression<Int>

query-model/jpql/src/test/kotlin/com/linecorp/kotlinjdsl/querymodel/jpql/expression/ExpressionsTest.kt

@@ -53,6 +53,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlUpper
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlValue
 import com.linecorp.kotlinjdsl.querymodel.jpql.path.Paths
 import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.Predicates
+import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.impl.JpqlIndex
 import com.linecorp.kotlinjdsl.querymodel.jpql.select.impl.JpqlSelectQuery
 import com.linecorp.kotlinjdsl.querymodel.jpql.sort.Sorts
 import org.assertj.core.api.WithAssertions
@@ -418,6 +419,19 @@ class ExpressionsTest : WithAssertions {
         assertThat(actual).isEqualTo(expected)
     }
 
+    @Test
+    fun index() {
+        // when
+        val actual = Expressions.index(path2)
+
+        // then
+        val expected = JpqlIndex(
+            path2,
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+
     @Test
     fun ln() {
         // when

render/jpql/src/main/kotlin/com/linecorp/kotlinjdsl/render/jpql/JpqlRenderContext.kt

@@ -53,6 +53,7 @@ import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlGreaterThanOrEqua
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlGreaterThanSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlInSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlInSubquerySerializer
+import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlIndexSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlInnerAssociationFetchJoinSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlInnerAssociationJoinSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlInnerFetchJoinSerializer
@@ -307,6 +308,7 @@ private class DefaultModule : JpqlRenderModule {
             JpqlGreaterThanOrEqualToAnySerializer(),
             JpqlGreaterThanOrEqualToSerializer(),
             JpqlGreaterThanSerializer(),
+            JpqlIndexSerializer(),
             JpqlInnerAssociationFetchJoinSerializer(),
             JpqlInnerAssociationJoinSerializer(),
             JpqlInnerFetchJoinSerializer(),

render/jpql/src/main/kotlin/com/linecorp/kotlinjdsl/render/jpql/serializer/impl/JpqlIndexSerializer.kt

@@ -0,0 +1,26 @@
+package com.linecorp.kotlinjdsl.render.jpql.serializer.impl
+
+import com.linecorp.kotlinjdsl.Internal
+import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.impl.JpqlIndex
+import com.linecorp.kotlinjdsl.render.RenderContext
+import com.linecorp.kotlinjdsl.render.jpql.serializer.JpqlRenderSerializer
+import com.linecorp.kotlinjdsl.render.jpql.serializer.JpqlSerializer
+import com.linecorp.kotlinjdsl.render.jpql.writer.JpqlWriter
+import kotlin.reflect.KClass
+
+@Internal
+class JpqlIndexSerializer : JpqlSerializer<JpqlIndex<*, *>> {
+    override fun handledType(): KClass<JpqlIndex<*, *>> {
+        return JpqlIndex::class
+    }
+
+    override fun serialize(part: JpqlIndex<*, *>, writer: JpqlWriter, context: RenderContext) {
+        val delegate = context.getValue(JpqlRenderSerializer)
+
+        writer.write("INDEX")
+
+        writer.writeParentheses {
+            delegate.serialize(part.path, writer, context)
+        }
+    }
+}

render/jpql/src/test/kotlin/com/linecorp/kotlinjdsl/render/jpql/serializer/impl/JpqlIndexSerializerTest.kt

@@ -0,0 +1,55 @@
+package com.linecorp.kotlinjdsl.render.jpql.serializer.impl
+
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expressions
+import com.linecorp.kotlinjdsl.querymodel.jpql.path.Paths
+import com.linecorp.kotlinjdsl.querymodel.jpql.predicate.impl.JpqlIndex
+import com.linecorp.kotlinjdsl.render.TestRenderContext
+import com.linecorp.kotlinjdsl.render.jpql.entity.book.Book
+import com.linecorp.kotlinjdsl.render.jpql.serializer.JpqlRenderSerializer
+import com.linecorp.kotlinjdsl.render.jpql.serializer.JpqlSerializerTest
+import com.linecorp.kotlinjdsl.render.jpql.writer.JpqlWriter
+import io.mockk.impl.annotations.MockK
+import io.mockk.verifySequence
+import org.assertj.core.api.WithAssertions
+import org.junit.jupiter.api.Test
+
+@JpqlSerializerTest
+class JpqlIndexSerializerTest : WithAssertions {
+    private val sut = JpqlIndexSerializer()
+
+    @MockK
+    private lateinit var writer: JpqlWriter
+
+    @MockK
+    private lateinit var serializer: JpqlRenderSerializer
+
+    private val expression1 = Paths.path(Book::authors)
+
+    @Test
+    fun handledType() {
+        // when
+        val actual = sut.handledType()
+
+        // then
+        assertThat(actual).isEqualTo(JpqlIndex::class)
+    }
+
+    @Test
+    fun serialize() {
+        // given
+        val part = Expressions.index(
+            path = expression1,
+        )
+        val context = TestRenderContext(serializer)
+
+        // when
+        sut.serialize(part as JpqlIndex<*, *>, writer, context)
+
+        // then
+        verifySequence {
+            writer.write("INDEX")
+            writer.writeParentheses(any())
+            serializer.serialize(expression1, writer, context)
+        }
+    }
+}