Implement power operator

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

@@ -227,6 +227,8 @@ locate("Book", path(Book::title))
 * FLOOR (floor)
 * INDEX (index)
 * LN (ln)
+* MOD (mod)
+* POWER (power)
 * SIGN (sign)
 * SQRT (sqrt)
 * ROUND (round)
@@ -247,6 +249,8 @@ ln(path(Book::price))
 
 mod(path(Employee::age), 3)
 
+power(path(Employee::age), 2)
+
 sign(path(Book::price))
 
 sqrt(path(Book::price))
@@ -256,10 +260,6 @@ round(path(Book::price), 2)
 size(path(Book::authors))
 ```
 
-| Function | DSL function |
-|----------|--------------|
-| POWER    | not yet      |
-
 ### Datetime functions
 
 * CURRENT\_DATE (currentDate)

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

@@ -223,6 +223,8 @@ locate("Book", path(Book::title))
 * FLOOR (floor)
 * INDEX (index)
 * LN (ln)
+* MOD (mod)
+* POWER (power)
 * SIGN (sign)
 * SQRT (sqrt)
 * ROUND (round)
@@ -243,6 +245,8 @@ ln(path(Book::price))
 
 mod(path(Employee::age), 3)
 
+power(path(Employee::age), 2)
+
 sign(path(Book::price))
 
 sqrt(path(Book::price))
@@ -252,10 +256,6 @@ round(path(Book::price), 2)
 size(path(Book::authors))
 ```
 
-| Function | DSL function |
-|----------|--------------|
-| POWER    | not yet      |
-
 ### Datetime functions
 
 * CURRENT\_DATE (currentDate)

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

@@ -646,6 +646,38 @@ open class Jpql : JpqlDsl {
         return Expressions.ln(value.toExpression())
     }
 
+    /**
+     * Create expression that calculates the powering of a numeric [base] to a specified [exponent].
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Any, V : Number> power(base: KProperty1<T, @Exact V>, exponent: Number): Expression<Double> {
+        return Expressions.power(Paths.path(base), Expressions.value(exponent))
+    }
+
+    /**
+     * Create expression that calculates the powering of a numeric [base] to a specified [exponent].
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Any, V : Number> power(base: KProperty1<T, @Exact V>, exponent: Expressionable<V>): Expression<Double> {
+        return Expressions.power(Paths.path(base), exponent.toExpression())
+    }
+
+    /**
+     * Create expression that calculates the powering of a numeric [base] to a specified [exponent].
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Number> power(base: Expressionable<T>, exponent: T): Expression<Double> {
+        return Expressions.power(base.toExpression(), Expressions.value(exponent))
+    }
+
+    /**
+     * Create expression that calculates the powering of a numeric [base] to a specified [exponent].
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Number> power(base: Expressionable<T>, exponent: Expressionable<T>): Expression<Double> {
+        return Expressions.power(base.toExpression(), exponent.toExpression())
+    }
+
     /**
      * Creates an expression that represents the sign of value.
      *

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

@@ -0,0 +1,74 @@
+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 PowerDslTest : WithAssertions {
+    private val intExpression1 = Paths.path(Employee::age)
+    private val intExpression2 = Expressions.value(2)
+
+    private val int1 = 2
+
+    @Test
+    fun `power() with a property`() {
+        // when
+        val expression1 = queryPart {
+            power(Employee::age, int1)
+        }.toExpression()
+
+        val expression2 = queryPart {
+            power(Employee::age, intExpression2)
+        }.toExpression()
+
+        val actual1: Expression<Number> = expression1 // for type check
+        val actual2: Expression<Number> = expression2 // for type check
+
+        // then
+        val expected1 = Expressions.power(
+            base = Paths.path(Employee::age),
+            exponent = Expressions.value(int1),
+        )
+
+        val expected2 = Expressions.power(
+            base = Paths.path(Employee::age),
+            exponent = intExpression2,
+        )
+
+        assertThat(actual1).isEqualTo(expected1)
+        assertThat(actual2).isEqualTo(expected2)
+    }
+
+    @Test
+    fun `power() with a expression`() {
+        // when
+        val expression1 = queryPart {
+            power(intExpression1, int1)
+        }.toExpression()
+
+        val expression2 = queryPart {
+            power(intExpression1, intExpression2)
+        }.toExpression()
+
+        val actual1: Expression<Number> = expression1 // for type check
+        val actual2: Expression<Number> = expression2 // for type check
+
+        // then
+        val expected1 = Expressions.power(
+            base = intExpression1,
+            exponent = Expressions.value(int1),
+        )
+
+        val expected2 = Expressions.power(
+            base = intExpression1,
+            exponent = intExpression2,
+        )
+
+        assertThat(actual1).isEqualTo(expected1)
+        assertThat(actual2).isEqualTo(expected2)
+    }
+}

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

@@ -40,6 +40,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlNullIf
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlParam
 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.JpqlPower
 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
@@ -277,6 +278,14 @@ object Expressions {
         return JpqlLn(value)
     }
 
+    /**
+     * Creates expression that calculates the powering of a numeric [base] to a specified [exponent].
+     */
+    @SinceJdsl("3.4.0")
+    fun <T : Number> power(base: Expression<T>, exponent: Expression<T>): Expression<Double> {
+        return JpqlPower(base, exponent)
+    }
+
     /**
      * Creates an expression that represents the sign of a numeric value.
      */

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

@@ -0,0 +1,13 @@
+package com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl
+
+import com.linecorp.kotlinjdsl.Internal
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expression
+
+/**
+ * Expression that calculates the powering of a numeric [base] to a specified [exponent].
+ */
+@Internal
+data class JpqlPower<T : Number> internal constructor(
+    val base: Expression<T>,
+    val exponent: Expression<T>,
+) : Expression<Double>

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

@@ -42,6 +42,7 @@ import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlNullIf
 import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlParam
 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.JpqlPower
 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
@@ -428,6 +429,20 @@ class ExpressionsTest : WithAssertions {
         assertThat(actual).isEqualTo(expected)
     }
 
+    @Test
+    fun power() {
+        // when
+        val actual = Expressions.power(doubleExpression1, intExpression1)
+
+        // then
+        val expected = JpqlPower(
+            doubleExpression1,
+            intExpression1,
+        )
+
+        assertThat(actual).isEqualTo(expected)
+    }
+
     @Test
     fun sign() {
         // when

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

@@ -105,6 +105,7 @@ import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPathPropertySeria
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPathTreatSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPathTypeSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPlusSerializer
+import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPowerSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlPredicateParenthesesSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlRoundSerializer
 import com.linecorp.kotlinjdsl.render.jpql.serializer.impl.JpqlSelectQuerySerializer
@@ -367,6 +368,7 @@ private class DefaultModule : JpqlRenderModule {
             JpqlPathTreatSerializer(),
             JpqlPathTypeSerializer(),
             JpqlPlusSerializer(),
+            JpqlPowerSerializer(),
             JpqlPredicateParenthesesSerializer(),
             JpqlRoundSerializer(),
             JpqlSelectQuerySerializer(),

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

@@ -0,0 +1,31 @@
+package com.linecorp.kotlinjdsl.render.jpql.serializer.impl
+
+import com.linecorp.kotlinjdsl.Internal
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPower
+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 JpqlPowerSerializer : JpqlSerializer<JpqlPower<*>> {
+    override fun handledType(): KClass<JpqlPower<*>> {
+        return JpqlPower::class
+    }
+
+    override fun serialize(part: JpqlPower<*>, writer: JpqlWriter, context: RenderContext) {
+        val delegate = context.getValue(JpqlRenderSerializer)
+
+        writer.write("POWER")
+
+        writer.writeParentheses {
+            delegate.serialize(part.base, writer, context)
+
+            writer.write(",")
+            writer.write(" ")
+
+            delegate.serialize(part.exponent, writer, context)
+        }
+    }
+}

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

@@ -0,0 +1,60 @@
+package com.linecorp.kotlinjdsl.render.jpql.serializer.impl
+
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.Expressions
+import com.linecorp.kotlinjdsl.querymodel.jpql.expression.impl.JpqlPower
+import com.linecorp.kotlinjdsl.querymodel.jpql.path.Paths
+import com.linecorp.kotlinjdsl.render.TestRenderContext
+import com.linecorp.kotlinjdsl.render.jpql.entity.employee.Employee
+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.Assertions.assertThat
+import org.junit.jupiter.api.Test
+
+@JpqlSerializerTest
+class JpqlPowerSerializerTest {
+    private val sut = JpqlPowerSerializer()
+
+    @MockK
+    private lateinit var writer: JpqlWriter
+
+    @MockK
+    private lateinit var serializer: JpqlRenderSerializer
+
+    private val expression1 = Paths.path(Employee::age)
+    private val expression2 = Expressions.value(2)
+
+    @Test
+    fun handledType() {
+        // when
+        val actual = sut.handledType()
+
+        // then
+        assertThat(actual).isEqualTo(JpqlPower::class)
+    }
+
+    @Test
+    fun serialize() {
+        // given
+        val part = Expressions.power(
+            base = expression1,
+            exponent = expression2,
+        )
+        val context = TestRenderContext(serializer)
+
+        // when
+        sut.serialize(part as JpqlPower<*>, writer, context)
+
+        // then
+        verifySequence {
+            writer.write("POWER")
+            writer.writeParentheses(any())
+            serializer.serialize(expression1, writer, context)
+            writer.write(",")
+            writer.write(" ")
+            serializer.serialize(expression2, writer, context)
+        }
+    }
+}