Add non-inline overload for convertTo that accepts KType.

Author: nikitinas

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/cast.kt

@@ -19,7 +19,7 @@ import kotlin.reflect.typeOf
 
 public fun <T> AnyFrame.cast(): DataFrame<T> = this as DataFrame<T>
 
-public inline fun <reified T> AnyFrame.cast(verify: Boolean = true): DataFrame<T> = if (verify) convertToImpl(typeOf<T>(), allowConversion = false, ExtraColumns.Keep)
+public inline fun <reified T> AnyFrame.cast(verify: Boolean = true): DataFrame<T> = if (verify) convertToImpl(typeOf<T>(), allowConversion = false, ExtraColumns.Keep).cast()
 else cast()
 
 public fun <T> AnyRow.cast(): DataRow<T> = this as DataRow<T>

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/convertTo.kt

@@ -3,12 +3,15 @@ package org.jetbrains.kotlinx.dataframe.api
 import org.jetbrains.kotlinx.dataframe.AnyFrame
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.impl.api.convertToImpl
+import kotlin.reflect.KType
 import kotlin.reflect.typeOf
 
 public enum class ExtraColumns { Remove, Keep, Fail }
 
 // region DataFrame
 
-public inline fun <reified T> AnyFrame.convertTo(extraColumnsBehavior: ExtraColumns = ExtraColumns.Keep): DataFrame<T> = convertToImpl(typeOf<T>(), true, extraColumnsBehavior)
+public inline fun <reified T> AnyFrame.convertTo(extraColumnsBehavior: ExtraColumns = ExtraColumns.Keep): DataFrame<T> = convertTo(typeOf<T>(), extraColumnsBehavior).cast()
+
+public fun AnyFrame.convertTo(schemaType: KType, extraColumnsBehavior: ExtraColumns = ExtraColumns.Keep): AnyFrame = convertToImpl(schemaType, true, extraColumnsBehavior)
 
 // endregion

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/impl/api/convertTo.kt

@@ -2,10 +2,8 @@ package org.jetbrains.kotlinx.dataframe.impl.api
 
 import org.jetbrains.kotlinx.dataframe.AnyFrame
 import org.jetbrains.kotlinx.dataframe.DataColumn
-import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.api.ExtraColumns
 import org.jetbrains.kotlinx.dataframe.api.asColumnGroup
-import org.jetbrains.kotlinx.dataframe.api.cast
 import org.jetbrains.kotlinx.dataframe.api.convertTo
 import org.jetbrains.kotlinx.dataframe.api.name
 import org.jetbrains.kotlinx.dataframe.api.toDataFrame
@@ -22,7 +20,7 @@ import kotlin.reflect.KType
 import kotlin.reflect.jvm.jvmErasure
 
 @PublishedApi
-internal fun <T> AnyFrame.convertToImpl(type: KType, allowConversion: Boolean, extraColumns: ExtraColumns): DataFrame<T> {
+internal fun AnyFrame.convertToImpl(type: KType, allowConversion: Boolean, extraColumns: ExtraColumns): AnyFrame {
     fun AnyFrame.convertToSchema(schema: DataFrameSchema): AnyFrame {
         if (ncol == 0) return schema.createEmptyDataFrame()
         var visited = 0
@@ -83,5 +81,5 @@ internal fun <T> AnyFrame.convertToImpl(type: KType, allowConversion: Boolean, e
 
     val clazz = type.jvmErasure
     val marker = MarkersExtractor[clazz]
-    return convertToSchema(marker.schema).cast()
+    return convertToSchema(marker.schema)
 }

core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/testSets/person/DataFrameTests.kt

@@ -2164,7 +2164,7 @@ class DataFrameTests : BaseTest() {
         df.add("col") { 1 }.convertTo<Target>(ExtraColumns.Remove) shouldBe df
 
         val added = df.add("col") { 1 }
-        added.convertToImpl<Target>(typeOf<Target>(), allowConversion = true, ExtraColumns.Keep) shouldBe added
+        added.convertTo(typeOf<Target>(), ExtraColumns.Keep) shouldBe added
 
         shouldThrow<IllegalArgumentException> {
             df.remove { city }.convertTo<Target>()
@@ -2175,7 +2175,7 @@ class DataFrameTests : BaseTest() {
         }
 
         shouldThrow<IllegalArgumentException> {
-            df.convert { age }.toStr().convertToImpl<Target>(typeOf<Target>(), allowConversion = false, ExtraColumns.Remove)
+            df.convert { age }.toStr().convertToImpl(typeOf<Target>(), allowConversion = false, ExtraColumns.Remove)
         }
 
         shouldThrow<IllegalArgumentException> {