Support Arithmetic function SIZE

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

@@ -228,6 +228,7 @@ locate("Book", path(Book::title))
 * LN (ln)
 * ROUND (round)
 * SIGN (sign)
+* SIZE (size)
 * SQRT (sqrt)
 
 ```kotlin
@@ -245,14 +246,15 @@ round(path(Book::price), 2)
 
 sign(path(Book::price))
 
+size(path(Book::authors))
+
 sqrt(path(Book::price))
 ```
 
 | Function | DSL function |
 |----------|--------------|
 | MOD      | not yet      |
 | POWER    | not yet      |
-| SIZE     | not yet      |
 | INDEX    | not yet      |
 
 ### Datetime functions

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

@@ -224,6 +224,7 @@ locate("Book", path(Book::title))
 * LN (ln)
 * ROUND (round)
 * SIGN (sign)
+* SIZE (size)
 * SQRT (sqrt)
 
 ```kotlin
@@ -241,14 +242,15 @@ round(path(Book::price), 2)
 
 sign(path(Book::price))
 
+size(path(Book::authors))
+
 sqrt(path(Book::price))
 ```
 
 | Function | DSL function |
 |----------|--------------|
 | MOD      | not yet      |
 | POWER    | not yet      |
-| SIZE     | not yet      |
 | INDEX    | not yet      |
 
 ### Datetime functions

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

@@ -690,6 +690,22 @@ open class Jpql : JpqlDsl {
         return Expressions.sqrt(value.toExpression())
     }
 
+    /**
+     * Creates an expression that the number of elements of the collection.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Any, V, S : Collection<V>> size(expr: KProperty1<T, @Exact S>): Expression<Int> {
+        return Expressions.size(Paths.path(expr))
+    }
+
+    /**
+     * Creates an expression that the number of elements of the collection.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T, S : Collection<T>> size(path: Pathable<S>): Expression<Int> {
+        return Expressions.size(path.toPath())
+    }
+
     /**
      * Creates an expression that represents the count of non-null values.
      *

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

@@ -0,0 +1,47 @@
+package com.linecorp.kotlinjdsl.dsl.jpql.expression
+
+import com.linecorp.kotlinjdsl.dsl.jpql.entity.employee.Employee
+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 SizeDslTest : WithAssertions {
+    private val path1 = Paths.path(Employee::departments)
+
+    @Test
+    fun `size() with property`() {
+        // when
+        val expression = queryPart {
+            size(Employee::departments)
+        }.toExpression()
+
+        val actual: Expression<Int> = expression // for type check
+
+        // then
+        val expected = Expressions.size(
+            path = Paths.path(Employee::departments),
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+
+    @Test
+    fun `size() with path`() {
+        // when
+        val expression = queryPart {
+            size(path1)
+        }.toExpression()
+
+        val actual: Expression<Int> = expression // for type check
+
+        // then
+        val expected = Expressions.size(
+            path = path1,
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+}

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

@@ -37,6 +37,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPathType
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPlus
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlRound
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSign
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSize
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSqrt
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSubquery
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSubstring
@@ -282,6 +283,14 @@ object Expressions {
         return JpqlSqrt(value)
     }
 
+    /**
+     * Creates an expression that represents the number of elements of the collection.
+     */
+    @SinceJdsl("3.4.0")
+    fun <T, S : Collection<T>> size(path: Path<S>): Expression<Int> {
+        return JpqlSize(path)
+    }
+
     /**
      * Creates an expression that represents the count of non-null values.
      *

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

@@ -0,0 +1,10 @@
+package com.linecorp.kotlinjdsl.querymodel.jpql.expression.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 JpqlSize<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

@@ -39,6 +39,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPathType
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPlus
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlRound
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSign
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSize
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSqrt
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSubquery
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlSubstring
@@ -91,6 +92,7 @@ class ExpressionsTest : WithAssertions {
     private val entity1 = Entities.entity(Employee::class)
 
     private val path1 = Paths.path(Employee::employeeId)
+    private val path2 = Paths.path(Employee::departments)
 
     private val predicate1 = Predicates.equal(Paths.path(Book::price), Expressions.value(BigDecimal.valueOf(100)))
     private val predicate2 = Predicates.equal(Paths.path(Book::price), Expressions.value(BigDecimal.valueOf(200)))
@@ -469,6 +471,19 @@ class ExpressionsTest : WithAssertions {
         assertThat(actual).isEqualTo(expected)
     }
 
+    @Test
+    fun size() {
+        // when
+        val actual = Expressions.size(path2)
+
+        // then
+        val expected = JpqlSize(
+            path2,
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+
     @ParameterizedTest
     @ValueSource(booleans = [true, false])
     fun count(distinct: Boolean) {

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

@@ -103,6 +103,7 @@ import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPredicateParenthe
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlRoundSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSelectQuerySerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSignSerializer
+import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSizeSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSortSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSqrtSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSubquerySerializer
@@ -358,6 +359,7 @@ private class DefaultModule : JpqlRenderModule {
             JpqlRoundSerializer(),
             JpqlSelectQuerySerializer(),
             JpqlSignSerializer(),
+            JpqlSizeSerializer(),
             JpqlSortSerializer(),
             JpqlSqrtSerializer(),
             JpqlSubquerySerializer(),

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

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

render/jpql/src/test/kotlin/com/linecorp/kotlinjdsl/render/jpql/serializer/impl/JpqlSizeSerializerTest.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.expression.impl.JpqlSize
+import com.linecorp.kotlinjdsl.querymodel.jpql.path.Paths
+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 JpqlSizeSerializerTest : WithAssertions {
+    private val sut = JpqlSizeSerializer()
+
+    @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(JpqlSize::class)
+    }
+
+    @Test
+    fun serialize() {
+        // given
+        val part = Expressions.size(
+            path = expression1,
+        )
+        val context = TestRenderContext(serializer)
+
+        // when
+        sut.serialize(part as JpqlSize<*, *>, writer, context)
+
+        // then
+        verifySequence {
+            writer.write("SIZE")
+            writer.writeParentheses(any())
+            serializer.serialize(expression1, writer, context)
+        }
+    }
+}