init research

dataframe/plugins/kotlin-dataframe/testData/selectionDslTestUtils.kt

@@ -0,0 +1,60 @@
+import org.jetbrains.kotlinx.dataframe.*
+import org.jetbrains.kotlinx.dataframe.annotations.*
+import org.jetbrains.kotlinx.dataframe.api.*
+import org.jetbrains.kotlinx.dataframe.io.*
+import org.jetbrains.kotlinx.dataframe.schema.DataFrameSchema
+
+@DataSchema
+interface Name {
+    val firstName: String
+    val lastName: String
+}
+
+@DataSchema
+interface Person {
+    val name: DataRow<Name>
+    val age: Int
+    val city: String?
+    val weight: Int?
+    val isHappy: Boolean
+}
+
+@DataSchema
+interface FirstNames {
+    val firstName: String
+    val secondName: String?
+    val thirdName: String?
+}
+
+@DataSchema
+interface Name2 {
+    val firstName: DataRow<FirstNames>
+    val lastName: String
+}
+
+@DataSchema
+interface Person2 {
+    val name: DataRow<Name2>
+    val age: Int
+    val city: String?
+    val weight: Int?
+    val isHappy: Boolean
+}
+
+val df = dataFrameOf("firstName", "lastName", "age", "city", "weight", "isHappy")(
+    "Alice", "Cooper", 15, "London", 54, true,
+    "Bob", "Dylan", 45, "Dubai", 87, true,
+    "Charlie", "Daniels", 20, "Moscow", null, false,
+    "Charlie", "Chaplin", 40, "Milan", null, true,
+    "Bob", "Marley", 30, "Tokyo", 68, true,
+    "Alice", "Wolf", 20, null, 55, false,
+    "Charlie", "Byrd", 30, "Moscow", 90, true,
+).group("firstName", "lastName").into("name").cast<Person>(verify = false)
+
+val dfGroup = run {
+    df.add {
+        "secondName" from { "".takeIf { false } }
+        "thirdName" from { "".takeIf { false } }
+    }.move { name.firstName and secondName and thirdName }.under { name.firstName }.cast<Person2>(verify = false)
+}
+